JP2011516808A - System and method for generation of two-phase coolant and determination of its cooling capacity - Google Patents

Abstract

  The present invention provides a system and apparatus for producing a two-phase coolant such as an ice slurry. Also, a method of producing a two-phase coolant, and a method of lowering or maintaining a low temperature in a subject, system, object, device, or application where a specific low temperature is desired using the two-phase coolant, Is provided. In addition, a system for determining the cooling capacity of the two-phase coolant is provided.

Description

  The present invention relates generally to the field of refrigeration and cooling. Specifically, the present invention relates to a system for producing a coolant such as a two-phase coolant and a system for measuring the cooling capacity of a coolant such as a two-phase, liquid-solid coolant.

Many industries require cooling systems for a wide variety of applications. In many cases, cold air or ice is generated for the desired application using a coolant chemical or a cooling machine. Various cooling systems have been proposed, but there is still a need for improved cooling systems in the industry.
Cross-reference to related applications

  This application claims priority from US Provisional Application No. 61 / 037,949 filed on Mar. 19, 2008 and International Patent Application No. PCT / US2008 / 080435 filed on Oct. 20, 2008. . The disclosure of each application is incorporated herein by reference in its entirety for all purposes.

  In certain aspects, the present invention provides a system for producing a two-phase coolant. The system includes a first container, a homogenizer coupled to receive a first fluid from the first container, a valve arranged to control the flow of the first fluid from the first container to the homogenizer, and the A second container coupled to discharge the second fluid to the homogenizer is included. The first container is configured to maintain the first fluid at a temperature below the freezing point of the first fluid at atmospheric pressure, and substantially instantaneously when the first fluid is released from the first container. Pressurized to a high pressure level sufficient to cause freezing of one fluid. The second container is configured to maintain the second fluid at a temperature below the freezing point of the first fluid at atmospheric pressure. The homogenizer includes an opening for the release of the generated coolant.

  In another aspect, the present invention provides a method for producing a coolant, such as a two-phase coolant. The method discharges a first fluid cooled from a pressurized container to a temperature below the freezing point at atmospheric pressure along with a carrier fluid cooled to a temperature below the freezing point at atmospheric pressure of the first fluid. Mixing with the particulate solid produced by the process. The pressure in the container is preferably high enough to cause a substantially instantaneous freezing of the first fluid when released from the container. In some embodiments, the particulate solid is ice. The first fluid or carrier fluid may be an aqueous or non-polar fluid. The aqueous fluid may be a physiologically compatible buffer or may include one or more salts, sugars, biomolecules, surfactants, or emulsifiers.

  The present invention also provides a method of inducing hypothermia in a subject. The method includes administering to the subject a particulate biphasic coolant that is pharmaceutically acceptable in an amount sufficient to induce hypothermia in the subject. The subject can be any animal, but is preferably a human. The hypothermic condition may be systemic or localized to one or more specific organs, tissues, places, cavities, spaces, or areas of the body.

  The present invention further provides a method for cooling perishable articles. The method includes producing a particulate two-phase coolant and exposing a perishable article to the coolant. Perishable articles are food or beverages, chemicals, drugs, or pharmaceutical compounds or compositions, cells, tissues, biological fluids, organs, and the like.

  The present invention further provides a method for cooling an apparatus. In some preferred embodiments, the device is a weapon. The method includes producing a particulate two-phase coolant and exposing the device to the coolant. Examples of weapons include guns, cannons, and laser weapons.

  A method for cooling the room is also provided. Such methods include producing a particulate two-phase coolant, exposing the air to the coolant, and circulating the cooled air throughout at least one chamber.

  In another aspect, the present invention provides a system for determining the cooling capacity of a two-phase, solid-liquid coolant. A length of conduit having known heat transfer characteristics receives a two-phase, solid-liquid coolant flow at a predetermined flow rate. A heat source is arranged to transfer heat to the coolant flowing inside the conduit. At least one heat flux sensor and at least one temperature sensor are disposed in the conduit to measure heat transfer to the coolant and the temperature of the coolant as a function of the distance that the coolant passes through the conduit. Electronics connected to the temperature sensor and the heat flux sensor calculate the cooling capacity of the coolant using the heat transfer to the coolant measured in the conduit and the change in coolant temperature.

  In another aspect, the present invention provides a system for detecting solid porosity and solid particle size in a two-phase, solid-liquid coolant. A length of conduit having known heat transfer characteristics, having an interior and an exterior and having an inlet and an outlet, receives a two-phase, solid-liquid coolant flow at a predetermined volumetric flow rate. A heat source is arranged to transfer heat to the coolant flowing inside the conduit. The conduit has at least one heat flux sensor arranged to measure heat transfer to the coolant as a function of the distance that the coolant passes through the conduit. The conduit further has at least one temperature sensor arranged to measure the coolant temperature inside the conduit as a function of the distance that the coolant passes through the conduit. Using the measured heat transfer and temperature, electronics coupled to the temperature sensor and the heat flux sensor determine the solid porosity and solid particle size of the coolant.

    In another aspect, the present invention provides a method for determining the cooling capacity of a two-phase, solid-liquid coolant. Heat is transferred to a flow of two-phase, solid-liquid coolant at a predetermined flow rate through a predetermined length of conduit having an interior and an exterior and having known heat transfer characteristics. Heat transfer to the coolant flow in the conduit and coolant temperature are measured as a function of the distance the coolant travels through the conduit. The cooling capacity of the coolant is calculated using the measured heat transfer and coolant temperature.

  In another aspect, a method for detecting solid porosity and solid particle size in a two-phase, solid-liquid coolant is provided. Heat is transferred to a predetermined flow rate, two-phase, solid-liquid coolant that flows through a predetermined length of conduit having an interior and an exterior and having known heat transfer characteristics. Heat transfer to the coolant flow in the conduit and the temperature of the coolant in the conduit are measured as a function of the distance traveled by the coolant through the conduit. The measured heat transfer and coolant temperature are related to the solid porosity and solid particle size of the coolant, and the solid porosity and solid particle size of the coolant are calculated.

  The present invention also provides a system and apparatus for producing a two-phase coolant such as an ice slurry. In some embodiments, a system for producing an ice slurry comprising a commercially available low concentration salt water such as 0.45%, 0.9%, or 3.0% saline, a coolant such as dry ice or compressed gas, a low concentration A system is provided that includes a heat exchanger configured to control the freezing temperature of the brine and a heat source arranged to heat the ice slurry that results when the brine is frozen. The heat exchanger includes two concentric tubes, the inner tube is configured to produce ice slurry, and the outer tube cools the inner tube to allow some of the low concentration brine to freeze As a result, an ice slurry composed of a low-concentration salt solution of a liquid phase and a solid phase (frozen phase) is obtained. Ice slurry is about 0.001%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, Contains 75%, 80%, 85%, 90%, 95% or more solid phase ice. The heat exchanger may include a heat pipe such as an annular heat pipe.

  In some embodiments, the apparatus for generating the ice slurry is a housing, a drive shaft that includes a heat exchanger that includes at least one coolant and is configured to control a freezing temperature of a fluid, such as low concentration brine. A drive shaft configured to scrape ice from the side wall of the heat exchanger by rotating at least one scraper blade coupled to the drive shaft, to hold the bearing at the end of the drive shaft coupled to the heat exchanger An internal disk, a housing including a mixing vessel connected to a housing including a heat exchanger, and a blade for mixing, configured to receive ice slurry from the heat exchanger and receive high-concentration salt water Mixing containers.

  The heat exchanger may include two concentric tubes, the inner tube is configured for ice slurry formation and flow, and the outer tube is configured to cool the inner tube and freeze a portion of the low concentration brine. As a result, a low-concentration brine-ice slurry consisting of liquid phase brine and solid phase ice is obtained. The heat exchanger may include a heat pipe such as an annular heat pipe. The low concentration saline may be a commercially available medical saline such as 0.45%, 0.9%, or 3.0% saline. The high-concentration saline may be a commercially available medical saline such as 3.0%, 5.0%, or 7.5% saline.

  The apparatus can further include a pump. For example, the apparatus includes a first pump configured to transport ice slurry through one or more components of the apparatus, and a second pump configured to deliver coolant through the heat exchanger. Can be included. Any suitable coolant such as dry ice, dry ice-alcohol slurry, compressed gas, freezing point depressing water, ethylene glycol, or polyethylene glycol can be used.

  The present invention also provides kits for generating ice slurries, such as kits for generating ice slurries using the systems, apparatus, and methods described and exemplified herein. In some embodiments, the kit includes low concentration brine, at least one coolant, a heat exchanger configured to control the freezing temperature of the brine, and high concentration brine. The coolant may be any suitable coolant such as dry ice, compressed gas, and the like. The low concentration saline may be a commercially available medical saline such as 0.45%, 0.9%, or 3.0% saline. The high-concentration saline may be a commercially available medical saline such as 3.0%, 5.0%, or 7.5% saline.

  The heat exchanger may include two concentric tubes, the inner tube is configured for ice slurry formation and flow, and the outer tube cools the inner tube to allow some of the low-concentration salt water to freeze. As a result, a low-concentration saltwater-ice slurry consisting of liquid phase brine and solid phase ice is obtained. The heat exchanger may include a heat pipe such as an annular heat pipe.

  The present invention also provides a method for producing an ice slurry. The method includes contacting a generally low concentration brine with a heat exchanger that includes at least one coolant and is configured to control a freezing temperature of the brine. When the brine is brought into contact with the heat exchanger, a portion of the brine is frozen inside the heat exchanger and the remaining brine remains in a liquid state to form an ice slurry. The method includes the step of mixing high concentration brine with the ice slurry after the ice slurry is formed.

  The heat exchanger may include two concentric tubes, the inner tube is configured for ice slurry formation and flow, and the outer tube is configured to cool the inner tube and freeze a portion of the low concentration brine. As a result, an ice slurry consisting of a liquid phase and frozen low-concentration brine is obtained. The heat exchanger may include a heat pipe such as an annular heat pipe. The low concentration saline may be a commercially available medical saline such as 0.45%, 0.9%, or 3.0% saline. The high-concentration saline may be a commercially available medical saline such as 3.0%, 5.0%, or 7.5% saline. Ice slurry is about 0.001%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70% or more The solid phase brine may be included.

  The present invention also provides a method of inducing hypothermia in a subject. This method involves contacting low-concentration brine with a heat exchanger that includes at least one coolant and configured to control the freezing temperature of the brine, such that a portion of the brine is frozen in the heat exchanger. Administering to the subject an effective amount of a pharmaceutically acceptable ice slurry produced by the remaining saline remaining in a liquid state, and mixing a high concentration of saline with the ice slurry. The subject can be any animal, but is preferably a human. The hypothermic condition may be systemic throughout the subject's body or localized to a particular organ, tissue, location, cavity, space, or region of the subject.

  The present invention is further a method of producing a flowable ice slurry, wherein the liquid is subcooled, the subcooled liquid is moved in a stable flow through the passage, and the subcooled liquid is stabilized. A process comprising the steps of perturbing the resulting stream to induce ice nucleation in the supercooled liquid to produce a flowable ice slurry. In some aspects, the moving step may include moving in a steady flow through the tube or pipe. The moving step may include moving the supercooled liquid in a laminar flow through the passage or in a turbulent flow through the passage.

  In some preferred embodiments, the supercooling step may comprise supercooling the brine. The flowable ice slurry produced by these methods preferably contains from about 0% to about 80% ice. The flowable ice slurry may comprise about 0% to about 60% ice, or about 0% to about 30% ice. The flowable ice slurry may also contain at least about 20% ice. In some embodiments, the method further comprises removing heat from the ice slurry, for example by contacting the ice slurry with a heat exchanger. In some embodiments, the method further comprises reducing the free energy of the stable flow.

  The step of disturbing may include varying the pressure of the supercooled liquid in the passage, and further introducing a second supercooled liquid jet that impinges on a stable flow of the supercooled liquid. May include. The second supercooled liquid may optionally be different from or the same as the supercooled liquid. The perturbing step is optionally performed in a substantially closed system in which a second subcooled liquid is mixed with the subcooled liquid, or a second subcooled liquid is This is done in a partially open system that impacts the supercooled liquid.

  In some embodiments, the disturbing step includes ultrasonically disturbing the stable flow. In another aspect, the disturbing step includes generating vortices or vortices in a stable flow. In another aspect, the perturbing step preferably includes introducing an interface at a contact angle that lowers the free energy barrier. In another aspect, the step of perturbing includes introducing seed ice pieces that produce heterogeneous nucleation sites. In yet another aspect, the step of disturbing comprises contacting a stable flow with at least one stagnation point. The stagnation point may be at least one ice crystal, for example. The stagnation point may also be at least one trip.

  The trip may be located near the center of the supercooled liquid flow or near the periphery of the supercooled liquid flow. In some aspects, the trip may generate a vortex or a vortex. Preferred examples of suitable trips are post design trip, cross wire trip, tooth design trip, central tooth design trip, sticky sphere trip, pyramid type It can be selected from the group consisting of trips, surface roughness trips, teeth combination trips, dimpled tube trips, and bladed conical trips, or combinations thereof.

  In some preferred embodiments of the method, the supercooling step comprises supercooling the high concentration liquid, subcooling the water, and subcooling the high concentration liquid and the supercooled water. Mixing to produce a flowable ice slurry.

  The present invention is also a method for producing a flowable ice slurry comprising supercooling a high concentration liquid, subcooling water, or subcooling a less concentrated liquid, Mixing a highly concentrated liquid with supercooled water or a less highly concentrated liquid to form a supercooled solution, moving the supercooled solution through a passage in a stable flow; and A method is provided that includes the steps of perturbing a stable flow of a cooled solution to induce ice nucleation in the supercooled solution to produce a flowable ice slurry.

  The present invention is also a system for generating an ice slurry, wherein the heat exchanger is configured to supercool a liquid solution, and is coupled to receive a stable flow of the supercooled liquid solution from the heat exchanger. And a means associated with the passage for perturbing a stable flow of the supercooled liquid in the passage to induce ice nucleation in the supercooled liquid to produce a flowable ice slurry; A system including In some aspects, the perturbing means includes a jet configured to introduce a supercooled liquid that impinges on the supercooled liquid solution. In another aspect, the means for disturbing includes an ultrasonic transducer. In another aspect, the perturbing means includes at least one vortex or vortex shedding point. In another aspect, the perturbing step preferably includes introducing a contact angle interface that lowers the free energy barrier. In another aspect, the step of perturbing includes introducing seed ice pieces that produce heterogeneous nucleation sites. In yet another aspect, the disturbing means includes at least one stagnation point such as a trip.

  The trip may be located near the center of the supercooled liquid flow or near the periphery of the supercooled liquid flow. In some aspects, the trip may generate a vortex or a vortex. Preferred examples of suitable trips are post design trips, cross-wire trips, tooth design trips, central tooth design trips, sticky sphere trips, pyramid trips, surface roughness trips. , Tooth profile combinations / trips, dimple tube trips, and bladed conical trips, or combinations thereof.

  The system can include at least one interface that reduces the surface energy of the supercooled liquid solution. The system can further include an inlet arranged to introduce a supercooled liquid that mixes with the liquid solution. The system can further include a second heat exchanger coupled to receive the ice slurry from the disturbing means and configured to remove heat from the ice slurry.

  The present invention is also an apparatus for inducing ice nucleation in a supercooled liquid configured to be coupled to a supercooled liquid source so as to receive a stable flow of the supercooled liquid. At least one stagnation point, at least one vortex or vortex shedding point associated with said conduit arranged to disturb a stable flow of supercooled liquid, and at least one vortex or vortex discharge point, or at least A contact angle interface that lowers one free energy barrier, wherein the at least one stagnation point, at least one vortex or vortex shedding point, or at least one interface nucleates ice in the supercooled liquid An apparatus for producing a flowable ice slurry is provided. The at least one stagnation point, at least one vortex or vortex shedding point, or at least one interface may include a trip. Trips can be placed near the center of the aisle. Preferred examples of suitable trips are post design trips, cross-wire trips, tooth design trips, central tooth design trips, sticky sphere trips, pyramid trips, surface roughness trips. , Tooth profile combinations / trips, dimple tube trips, and bladed conical trips, or combinations thereof.

FIG. 2 is a schematic diagram illustrating an exemplary embodiment of a system for generating a two-phase coolant. 2 is a schematic diagram illustrating an exemplary embodiment of a system for measuring solid porosity and solid particle size of a two-phase, liquid-solid coolant. 2 is a schematic diagram showing the effect of particle size on heat flux measurement. 2 is a schematic diagram illustrating two nozzle embodiments that are compatible with the generation of ice from pressurized liquid. The shaded area is a surface that is heated or coated with a non-stick material to prevent internal ice formation and nozzle exit blockage. 2 is a schematic diagram illustrating two nozzle embodiments that are compatible with the generation of ice from pressurized liquid. The shaded area is a surface that is heated or coated with a non-stick material to prevent internal ice formation and nozzle exit blockage. 2 is a schematic diagram illustrating two nozzle embodiments that are compatible with the generation of ice from pressurized liquid. FIG. 1 is a schematic diagram illustrating an embodiment of a two-phase coolant generation system that utilizes phase change, unlike electrical refrigeration to promote freezing. It is an exploded view showing an embodiment of a two-phase coolant generating device. It is an exploded view showing an embodiment of a two-phase coolant generating device. FIG. 4 shows an embodiment of a housing for various components of a two-phase coolant generator. FIG. 4 shows an embodiment of a housing for various components of a two-phase coolant generator. FIG. 7 shows an embodiment of a heat exchanger that can be used in the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of a drive shaft that can be used with the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of a scraper blade that may be used with the coolant generation assembly illustrated in FIG. FIG. 7 illustrates an embodiment of an internal disk that can be used with the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of an internal disk that can be used with the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of an internal disk that can be used with the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of a two-phase coolant mixing blade that can be used in the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of a two-phase coolant mixing blade that can be used in the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of a two-phase coolant mixing blade that can be used in the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of a mixing vessel that can be used with the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of a mixing vessel housing that can be used with the coolant generation assembly shown in FIG. 6. FIG. 7 illustrates an embodiment of a heat exchanger that includes an annular heat pipe that can be used with the coolant generation assembly shown in FIG. 6. 1 is a schematic diagram illustrating an exemplary embodiment of a system including a heat pipe for measuring the solid porosity and particle size of a two-phase, liquid-solid coolant. It is a figure which shows the flow and temperature profile of the heat which generate | occur | produce by the slurry production | generation from a heat exchanger. It is a figure which shows the flow and temperature profile of the heat which generate | occur | produce by the slurry production | generation from a heat exchanger. FIG. 5 shows a heat flow and temperature profile showing the effect of a frozen plug in the coolant line on the operation of the slurry generation system. FIG. 5 shows a heat flow and temperature profile showing the effect of a frozen plug in the coolant line on the operation of the slurry generation system. FIG. 3 is a diagram showing heat flow and temperature profiles illustrating the effect of changes in the rotation speed of an ice scraper blade on the operation of an ice slurry generation system. FIG. 3 is a diagram showing heat flow and temperature profiles illustrating the effect of changes in the rotation speed of an ice scraper blade on the operation of an ice slurry generation system. FIG. 3 is a diagram showing heat flow and temperature profiles illustrating the effect of changes in the rotation speed of an ice scraper blade on the operation of an ice slurry generation system. 1 is a schematic diagram illustrating an embodiment of a disturbed nucleation system having a primary cooler and a secondary cooler. FIG. A representative data set showing ice nucleation initiated by two disturbance methods. A representative data set showing ice nucleation initiated by two disturbance methods. FIG. 3 shows various trip embodiments for inducing ice nucleation: (A) post; (B) cross wire; (C) tooth; (D) central tooth; (E) sticky spheres (sticky) sphere); (F) pyramid type; (G) surface roughness; (H) tooth profile combination; (I) dimpled tube; and (J) winged cone. FIG. 3 illustrates an exemplary embodiment of an ice nucleation chamber. FIG. 2 is a front view and a cross-sectional view illustrating an embodiment of a trip holder and spacer that can be used in an ice nucleation chamber. 1 is a front view illustrating an embodiment of an ice nucleation chamber. FIG. It is a figure which shows embodiment of the custom-order hose attachment port which has an O-ring pair surface. 1 is a cross-sectional view illustrating an exemplary embodiment of an ice nucleation chamber. FIG. 6 is a rear view illustrating an embodiment of an ice nucleation chamber. It is a front view which shows embodiment of the holder of a posttrip design. FIG. 6 is a cross-sectional view showing an embodiment of a post-trip design holder.

  Various terms relating to the systems, methods, and other aspects of the present invention are used throughout this specification and the claims. These terms should be construed in their ordinary meaning in the art unless otherwise specified.

  Various publications, including patents, published applications, technical papers and academic papers, are cited throughout the specification. Each cited publication is incorporated herein by reference in its entirety for all purposes.

  In accordance with aspects of the present invention, it has been discovered that a freezing point depression can be used to spontaneously freeze a fluid, which can be particulated and mixed with a carrier fluid to form an ice slurry. Furthermore, it has been discovered that the size of the fine particles can be controlled and fine tuned to be useful for specific applications. In addition, it has been discovered that the resulting slurry can be maintained and transported in a controlled environment to prevent undesired melting of frozen particles, prevent agglomeration, and prevent mixing of frozen fluid components and carrier fluids. It was. It has also been discovered that the slurry can be easily pumped by mixing the salt after the formation of ice crystals in a commercially available ice slurry generator.

  Accordingly, the present invention provides a cooling system that includes a system for producing a two-phase coolant. The figure shows an exemplary embodiment of the system of the present invention. In the exemplary embodiment shown in FIG. 1, the system includes a first container 10. The first container includes at least one opening for introducing the first fluid 14 into the container. The first fluid 14 is retained in the container 10 so as to be discharged. The first container 10 also includes at least one additional opening 16 for discharging the first fluid 14 from the container. The first container 10 is coupled to the homogenizer 18 such that the first fluid 14 is received by the homogenizer 18. Optionally, the first container 10 is coupled to the homogenizer 18 by a first tube 20.

  In some embodiments, the system includes a valve 22 arranged to control the flow of the first fluid 14 from the first container 10 to the homogenizer 18. Optionally, the valve can be coupled to the container 10, the first tube 20, or the homogenizer 18. An optional gasket 24 may be coupled to the first container 10 at the second opening 16, to the first tube 20, to the valve 22, or to the homogenizer 18. Since the coupling of the system components is not a complete fluid or airtight seal, the gasket 24 can be utilized to form a seal between the coupled components.

  The valve 22 may be a nozzle. A nebulizer or nozzle can be used to generate micron sized droplets of the fluid in question. The fluid is expected to undergo a liquid-to-solid phase transition when the droplet pressure returns to atmospheric pressure when ejected from the nozzle.

  FIG. 4 is a schematic diagram illustrating an exemplary nozzle structure that can be used to aid in the formation of the particleized ice of the present invention. FIG. 4A shows a cross section of a nozzle having multiple openings. FIG. 4B shows a cross section of a nozzle having a single opening. FIG. 4C shows a top view of a single aperture nozzle. For example, the nozzle 44 can form a fine mist from an exiting fluid having a plurality of small openings 46. The needle valve 48 can be used to control the flow rate by limiting the flow of fluid through the nozzle. In another example, the nozzle 50 has only a single opening 52, but the liquid exiting the hole has a much higher rotational speed, dramatically increasing the kinetic energy present in the flow, and thereby finer It has an internal shape that forms a mist. The nozzle 50 can also include a needle valve 54 that controls the flow of fluid through the nozzle.

  The nozzle preferably maintains a sufficiently high pressure so that it does not initiate a phase change, eg freezing, inside the nozzle as the fluid exits. The solidification of the fluid inside the nozzle can cause clogging of the space 56 through which the nozzle fluid flows or clogging of the openings. To reduce the possibility of a phase change before the fluid exits the nozzle, the opening 46 can be conical so that the outlet 58 has a minimum diameter.

  If the cone is insufficient to prevent fluid freezing at the nozzle, at least two non-limiting countermeasure options can be used to reduce or eliminate solidification and nozzle clogging. The first countermeasure is to create a small thermal boundary layer in the flow near the nozzle wall 56 using a resistance heating element (not shown). This boundary layer does not freeze, allowing the flow through the outlet to continue smoothly. The second measure is to reduce the adhesion energy between the fluid that exits the nozzle by applying a hydrophobic coating to the nozzle wall. This hydrophobic coating may also attract other hydrophobic elements that may be present in the outgoing fluid and help further reduce the adhesion energy between the outgoing fluid and the nozzle wall. .

  As shown in FIG. 1, the system also includes a second container 26. The second container 26 may be separated from the first container 10, concentric with it, or connected by other methods. FIG. 1 shows a separation configuration of two containers. The second container includes at least one opening 28 for introducing the second fluid 30 into the container. The second fluid 30 is releasably held in the container 26. The second container 26 also includes at least one additional opening 32 for discharging the second fluid 30 from the container. The second container 26 is coupled to the homogenizer 18 such that the second fluid 30 is received by the homogenizer 18. Optionally, the second container 26 is connected to the homogenizer 18 by a second tube 34. An optional gasket (not shown) can be attached to the second container with an opening 28, to the second tube 34, or to the homogenizer 18.

  The container can be made of any material suitable in the art, including but not limited to plastic, glass, rubber, metal, ceramic, and the like. The container may be transparent, translucent, opaque, or impermeable to light. Gaskets include, but are not limited to, elastomers and polymers based on silicon and carbon, thermoplastic elastomers, elastomers such as nitrile butadiene rubber, butyl rubber, siloxane, ethylene propyl diene monomer, etc. It may consist of any material.

  The homogenizer 18 functions to produce a uniform desired particle size and a desired slurry density, such as a solid particulate matter to fluid ratio. The homogenizer 18 includes at least one opening 36 for receiving the solidified fluid 14 discharged from the first container 10 and at least one opening 38 for receiving the second fluid 30 discharged from the second container 26. . In some embodiments, a single opening receives both the solidified fluid 14 emitted from the container 10 and the second fluid 30 emitted from the container 26. The homogenizer 18 includes at least one opening 40 for discharging the two-phase coolant produced by the homogenizer. Optionally, a third tube 42 can be coupled to the homogenizer 18 via the opening 40. The third tube 42 can be used to deliver coolant to a specific location, for example, to the location described and illustrated herein.

  Optionally, the system can include a pump (not shown). The pump can be coupled to the first container 10, the second container 26, or the homogenizer 18. Although the solidified first fluid 14 and second fluid 30 can be transported to the homogenizer 18 with force such as gravity and pressure released from the container 10, in some embodiments, a pump is used to assist in transport. It is preferable.

  In the process of filling the first container with liquid, the container is filled with a small volume that is less than full volume. For example, the fluid is filled to about half of the total volume, but may be filled with more or less. The container is then sealed and attached to the gas cylinder at approximately the required pressure. Any suitable gas can be used to supply the pressure, such as oxygen, carbon dioxide, nitrogen, or argon. The gas is then connected to the first container to supply the required pressure. The magnitude of the pressure can be varied according to variables such as fluid type and volatility, and the freezing point of the fluid at atmospheric pressure. Since the container is sealed, the pressure can be maintained at a desired level for an extended period of time. When the nozzle is opened to begin spraying, the pressure seal is broken.

  The pressure from the first container can be used to provide force for flow to the homogenizer to drive or take in fluid from the second container. If the container is concentric, the second fluid is taken up by the speed of the spray exiting the nozzle. In addition, the spray movement can optionally be changed to create a low pressure zone and its siphon action can draw fluid from the second tank. In the third option, the pressure in the second tank is connected to the nozzle outlet, and the pressure is increased at the nozzle outlet by the expansion of ice and gas. The pressure in the second container can be increased using the pressure. The flow from the second container can travel under the nozzle and pick up the particulate ice on the path to the delivery system.

  Also according to an exemplary embodiment of the present invention, a method for producing a coolant comprising a two-phase coolant is provided. In general, these methods involve mixing the granulated solid with a carrier fluid. The granulated solid is preferably micronized, more preferably nanoparticulate, and is produced by releasing a first fluid cooled to a temperature below the freezing point at atmospheric pressure from a pressurized container. The The first fluid is preferably frozen substantially instantaneously into a solid. Freezing is performed by an adiabatic method, for example. For example, the frozen fluid can be granulated using any suitable means in the art as described and exemplified herein. The pressure in the container is maintained at a level that causes a freezing point depression. The carrier fluid is also cooled to a temperature below the freezing point of the first fluid at atmospheric pressure. According to this embodiment, the granulated frozen first fluid is mixed with the carrier fluid to form a slurry, ie a two-phase solution, which is used as a coolant in a suitable application as described and exemplified herein. Can do. In some highly preferred embodiments, the biphasic solution is homogenized to a uniform particle size and / or a uniform solid to fluid ratio.

  In some embodiments, the first fluid and / or carrier fluid is aqueous or substantially aqueous. The aqueous fluid is water, alcohol, or a physiologically compatible buffer such as Hanks solution, Ringer solution, or physiological saline, but is not limited thereto. The first fluid and / or carrier fluid comprises at least one salt, monosaccharide or polysaccharide, or biomolecules such as nucleic acids, polypeptides, and lipids, or any analog, homologue, or derivative of the above. Can be included. Any salt, monosaccharide or polysaccharide that is known or suitable for the particular needs of the researcher can be used.

  The first fluid and / or the carrier fluid can include at least one emulsifier. Any emulsifier known or adapted to the specific needs of the application can be used. US FDA approved emulsifiers are highly preferred, especially for treatment of the resulting ice slurry or food-based applications. Non-limiting examples of such emulsifiers include glycerol, soybean oil, and egg lecithin.

  The first fluid and / or carrier fluid can include at least one surfactant. Any surfactant suitable for known or specific application needs can be used. Surfactants approved by the US FDA are highly preferred. For example, a series of surfactants made from polyethylene oxide (PEO), polypropylene oxide (PPO), or polyethylene glycol (PEG), and polypropylene glycol (PPG) subunits is particularly preferred. These surfactants have been shown to be non-toxic, are generally considered safe, and are known to be protective in cases of cell damage and microbubble embolism. Two series of surfactants are highly preferred: poloxamer surfactants (PEG and PPG copolymer surfactants); and pluronic surfactants (PEO and PPO copolymer surfactants).

  In some embodiments, the first fluid and / or carrier fluid is non-polar, such as an organic solvent. Any non-polar fluid known or suitable for the specific needs of the application can be used. Non-limiting examples of such fluids include perftran and perfluoro-x-anes such as perfluorodecane and perfluorohexane. The two-phase coolant may be any solid to fluid ratio suitable for the specific needs of the application. For example, this ratio ranges from 0.001% solids to 99.999% solids and the corresponding 99.999% fluid to 0.001% fluid. A solid porosity of at least about 10% in the fluid is preferred. More preferably at least about 15% solid porosity in the fluid, more preferably at least about 20% solid porosity, more preferably at least about 25% solid porosity, more preferably at least about 30% solid porosity. More preferably at least about 35% solid porosity, more preferably at least about 40% solid porosity, more preferably at least about 45% solid porosity, more preferably at least about 50% solid porosity, Preferably, a solid porosity of at least about 55% can be used. Even more preferred is a solid porosity of at least about 60% in the fluid, with a higher percentage being more preferred. Since it is preferable to maximize cooling at a given volume, it is highly desirable to achieve the highest percentage of solid porosity that can be achieved with the materials chosen to make up the final slurry. In some cases, solid porosity can be increased using chemical lubricants (emulsifiers and surfactants) and / or particle size modifiers.

  The present invention also provides a method of using a coolant, such as a two-phase coolant produced by the system and method of the present invention. This coolant can be used to cool or maintain a specific temperature in applications where lower temperatures or temperature maintenance is desired.

  Thus, the present invention provides a method for inducing or maintaining hypothermia in a subject. Such methods generally involve administering to a subject in need of a pharmaceutically acceptable coolant, such as a two-phase coolant produced according to any of the methods of the invention described and exemplified herein. Including. The cooling agent is administered in an amount effective to induce hypothermia in the subject. The effective amount depends on a variety of factors, which are believed to be known in the art. Non-limiting examples of such factors include subject species, height, weight, age, and the like. Administration can proceed by any means compatible with the particular application for which the coolant is used. For example, the coolant can be intravenously, intramuscularly, intraperitoneally, topically, orally, nasally, from the anus, into the uterus, into the thoracic cavity, into the lungs, other spaces, areas of the body. Etc. can be administered. Intravenous administration is highly preferred.

  These methods can be used on any subject. Preferably, these methods are used in mammals such as horses, cows, pigs, dogs, cats, rabbits, rats, hamsters, and mice. These methods are preferably used beneficially for humans.

  The hypothermic condition may be systemic. The implication is that hypothermia is induced and / or maintained throughout the subject's whole body. Alternatively, the hypothermic condition may relate to a specific location or locations of the body, for example, specific organs, appendages, cavities, spaces, or regions.

  Also provided is a method for rapidly cooling perishable articles or maintaining low temperatures. Such methods generally include generating a coolant, such as a two-phase coolant, according to the methods of the invention described or exemplified herein, and exposing perishable articles to the coolant. . Perishable articles refer to products, compounds, or compositions that have a finite shelf life. Non-limiting examples of perishable goods include foods such as meat, fish, agricultural products, milk and dairy products, confectionery, beverages, pharmaceuticals, vitamins, minerals, volatile chemicals, radionuclides, nucleic acids, polypeptides, lipids, etc. Biomolecules, cells, tissues, organs, and biological fluids such as blood, serum, urine, saliva, sweat, and milk.

  Also described is a method of rapidly cooling devices that generate heat, such as weapons and high power electronics. This method generally includes producing a coolant, such as a two-phase coolant, according to any of the methods of the invention described or exemplified herein, and exposing a weapon to the coolant. A weapon or part of a weapon, such as a magazine, can be cooled using the method of the present invention. Non-limiting examples of suitable weapons include guns, cannons, and electromagnetic pulse generators. Laser weapons can also be cooled according to the method of the present invention. The weapon may be held by hand or attached to equipment such as an airplane, helicopter, or vehicle. Non-limiting examples of high power electronics include computers, appliances, microelectronic devices, power transformers and the like.

  The present invention also describes a method for cooling a room. The method generally produces a coolant, such as a two-phase coolant, according to any of the methods of the invention described or exemplified herein, and exposes the air to the coolant such that the temperature of the air is reduced. And circulating cooled air throughout the room. The air can be exposed to the coolant by any means suitable in the art. Similarly, the cooled air can be circulated by any means such as a fan suitable in the art. The present invention contemplates that multiple rooms can be simultaneously cooled by the method of the present invention. For example, with appropriate ductwork, cooled air can be circulated simultaneously to multiple rooms including all rooms in a particular building.

  The present invention also describes a non-lethal crowd control method. For example, a large and high-pressure pump water discharge of a two-phase coolant from a cannon can be used to disperse a mobified crowd by causing severe cooling by abrupt cooling caused by the whole body being exposed to the two-phase coolant. .

  The present invention also describes a method for improving fire control or suppression methods. For example, a large and high-pressure pump discharge of a two-phase coolant from a fire hose allows the environmentally friendly two-phase coolant to absorb more heat from the fire, reducing the energy of the combustion process and controlling the fire And make the suppression easier. Furthermore, the release of ice slurry from the fire sprinkler system will have a similar effect on the fire.

  The present invention also describes a method for protecting a structural element when it is extremely hot. Non-limiting examples of extremely high heat include building fires, spacecraft re-entry, or metal refining equipment. Extremely hot conditions can lead to building collapse, spacecraft disassembly, or mechanical system failure where heat exceeds structural member limits. If the components of these systems were designed with a mass two-phase coolant generation system and provided with a complete heat transfer conduit, they would be cooled directly during high heat generation, increasing the time to collapse of the structure Will.

  Furthermore, the present invention describes a method for a personal cooling system. Individual cooling may help to improve individual behavior during physical activity or otherwise prevent overheating of the body. Non-limiting examples of personal cooling systems include personal mist generators, bench mist generators for sports teams, other clothing, equipment, helmets, gloves, shoes etc. to cool the desired part of the body There is a body cooling system, to wear.

  Furthermore, the present invention describes a method for the removal or safe handling of toxic gases. As the temperature of the liquid decreases, the amount of gas that can be dissolved in the liquid increases. The described method can be used to create a two-phase air wash liquid. This liquid can be used to rapidly filter air exposed to any of a variety of toxic gases. Non-limiting examples of toxic gases include carbon monoxide, toxic gases, radioactive gases, radioactive particulate matter, asbestos particulate matter, and the like. Another aspect of the same device allows for safe handling of weapons containing such gases.

  The present invention further describes a method for rapidly inducing deep hypothermia for the induction of a cryospastic condition. This method may be used for medical benefits in hospitals or may be used to induce stasis for long-term space travel. Locations that induce deep hypothermia will require different embodiments of the two-phase coolant generation system. Systems designed for use in space can use space vacuum as the primary coolant.

  The cooling rate can be controlled in any of the ways described above, or any other method to which the invention can be adapted. Thus, the cooling can proceed slowly or quickly, at a uniform rate, or at a stepped rate, for example, quickly during a period, followed by a slower period. The cooling rate can be determined and adjusted according to the specific needs of the application. The cooling rate can be controlled by any means suitable in the art. Suitable methods for controlling the cooling rate include, but are not limited to, adjusting the slurry delivery rate or adjusting the ice content of the slurry. The method used to control these parameters depends on the particular configuration of the device, but may include changing the pumping speed or changing the percentage that a valve or nozzle is open. It is believed that the cooling system provided by the present invention can be suitably used in a wide variety of other applications. Non-limiting examples of such applications include storage, shipping and air conditioning in various industries. Another application is found, for example, in the medical industry, where patient cooling is being recognized as a treatment that improves outcomes such as trauma, cardiac arrest, ischemic injury, and the like. Cooling is also beneficial for devices that generate excessive heat that damages the components of the device. Such devices include computers, weapons, tools, motors, vehicles, and the like.

  Depending on the application, refrigerant chemicals or refrigerators are optionally used to generate cold air or ice. However, since many of the refrigerant chemicals, such as chlorofluorocarbons, are toxic and can harm the environment, their cooling systems can be operated without the use of refrigerant chemicals. Is not preferable. Similarly, many commercial air conditioners and refrigeration units can use a large amount of energy, which can be a heavy burden on the power grid during peak demand, and can be operated without using a large amount of energy. It is not preferable compared to the embodiment described in the specification.

  Two-phase, solid-liquid coolants of the type described herein can be beneficially used in a variety of applications, such as medical, refrigeration, and HVAC applications, crowd control, and fire fighting. For some applications, it is particularly beneficial to verify the quality of such a coolant, i.e., the cooling capacity, at an activity site that uses the coolant. Therefore, a quality assurance system that allows reliable use of the two-phase coolant system in a variety of applications is desirable.

  The cooling capacity of a two-phase, solid-liquid coolant is related to the porosity and particle size of the coolant solids. A particle detector using ultrasound or light scattering is selectively used to make measurements that determine the cooling capacity. In applications where the required large power and computing power are not available, or where a clean and stable environment is not available, it can be tailored to different applications in unpredictable environments such as battlefields, emergencies, or at sea. It would be beneficial to have a quality assurance system that requires minimal power and computing power.

  As shown in FIG. 2, in a preferred embodiment, a two-phase, solid-liquid coolant has an interior 111 and an exterior 112 for determining the cooling capacity, a predetermined length, and A system 100 is provided that includes a conduit 110 having known heat transfer characteristics. The conduit may be made from a metal such as copper, aluminum, or stainless steel. The conduit can be swiveled so that laminar mixing occurs as the coolant travels through the quality measuring device. The internal dimensions of the swung conduit device can be the same dimensions as the inlet and outlet tubes, but will vary depending on the application. As a non-limiting example, the gastrointestinal delivery system is a larger conduit than the intravenous delivery system. Preferably, the outer diameter of the conduit does not exceed twice the inner diameter. The conduit 110 further has an inlet 113 and an outlet 114, each configured to receive and discharge a predetermined flow rate of coolant flowing through the interior 111 of the conduit 110. A heat source 120 is positioned relative to the conduit 110 to transfer heat to the coolant flowing through the interior 111 of the conduit. The heat source for the device can be optimally provided in the form of a series of resistance heating devices (RTDs) applied by an electric current. RTDs can be embedded in the wall of the conduit or can be mounted inside or outside the conduit. RTDs can be controlled to maintain a constant temperature. In addition, the RTD can incorporate a heat flux sensor and a temperature sensor. At least one heat flux sensor 121 and at least one temperature sensor 122 are positioned on the conduit 110. A sensor wire 123 couples the sensor to the electronics element 130, usually to a computer or other semiconductor device.

  In operation, a predetermined flow rate of two-phase, solid-liquid coolant, preferably an aqueous slurry of ice, is withdrawn from the outlet of the coolant delivery system and directed to the inlet 113 of the conduit 110. The coolant flow to conduit 110 is preferably drawn from a source as close as possible to the point where the coolant is used to determine the cooling capacity of the coolant at the point of use. Heat is transferred from the heat source 120 to the coolant flowing through the conduit interior 111. The exterior 112 of the conduit 110 is preferably maintained at a constant temperature. It is also preferred that a substantially uniform cross-sectional distribution of the solid phase in the coolant is maintained as the coolant passes through the conduit 110. There may be a swirl or vane in the conduit to induce mixing to ensure fluid uniformity.

  Heat transfer and coolant temperature are measured by heat flux sensors and temperature sensors 121 and 122 as a function of the distance that the coolant travels within the conduit interior 111. The signal is transmitted from the sensors 121 and 122 to the electronic element 130 such as a computer through the sensor wire 123. The electronics element 130 correlates with the measured heat flux to the coolant, coolant temperature, and various properties of the coolant: cooling capacity, solid porosity, and solid particle size. Using the heat flux and temperature measurements, the electronics element 130 calculates the associated coolant properties. As shown in FIG. 3, the decrease in solid particle size correlates with the increase in measured heat flux.

  The present invention also describes a portable system and method for on-demand production of a two-phase coolant. For example, when performing rapid cooling to induce hypothermia for treatment in the field, one obstacle is to cool a liquid such as saline to produce ice in a short period of time available to treat the patient. That is, a sufficient power source cannot be found. Furthermore, in the therapeutic context, patient cooling should ideally be initiated before arriving at the hospital, making it difficult to meet power needs, i.e., a large power source needs to be available in the ambulance. It means that there is.

  For example, the total energy required to cool 2 liters of salt water from about room temperature to a freezing point of about 0 ° C. and 1 liter of 2 liters to freeze into ice is about 550 kilojoules. . To carry out this process in about 5 minutes, more than 1.8 kilowatts of energy is required even assuming ideal conditions. Although there are refrigeration units with that type of cooling capacity, they typically require special 220 volt wiring and are generally large and heavy, weighing hundreds of pounds. Furthermore, in many cases the conditions are not ideal, so this estimate of power needs is underestimating the power actually required. That is, the refrigeration unit actually required is heavier and requires more power to operate. Size and power requirements limitations will limit the ability to generate two-phase coolant in an emergency in a hospital building, and the ability to generate such coolant in an ambulance under the constraints of an emergency medical situation. Even if you don't say it is impossible, it is strictly limited.

  To overcome these limitations, one possible method is to generate and store the two-phase coolant before it is needed. By preparing in advance, the flow rate of the coolant can be significantly reduced and the power consumption can be reduced. However, two-phase coolants such as slurries lose the preferred ice particle shape and pumping properties when stored, reducing the therapeutic value of the coolant. Aqueous ice slurries are in a state of constant phase change between the ice form and the liquid form of water. Over time, the dendritic nature of the ice crystals recovers and the slurry can no longer be moved by the pump, even under the strict constraints of, for example, an intravenous tube.

  It has been discovered by the present invention that, for example, the thermodynamic energy stored in compressed gas or dry ice can be controlled and used for mobile on-demand production of a two-phase coolant. However, the use of the thermodynamic energy of such a cooling liquid creates a temperature below the eutectic point of salt water, resulting in an ice slurry at a temperature well below 0 ° C., which is harmful to the patient. there is a possibility. This problem has been solved by the discovery that one or more heat exchangers can be used to control the freezing temperature of salt water. The use of heat exchangers also makes it possible to take advantage of cooling stored in the form of dry ice sublimation or liquid evaporation. An overview of the use of the heat exchanger is shown in FIG. Details of system embodiments of the present invention are described below with reference to FIGS. 6-14.

  The pressure drop, heat flow, and mass flow of a heat exchanger can be changed by changing its linear dimension. Skilled technicians see, for example, John E Hesselgreaves' “Compact Heat Exchangers: Selection, Design and Operation” (Elsevier Science LTD. 2001) for guidance on this point. can do. The dimensions of the devices described or illustrated herein are for purposes of illustration and not limitation. Thus, the dimensions will vary depending on the individual system, device, application, or needs of the individual user or researcher.

  In some embodiments, the two-phase coolant production system generally uses sterile saline-saline for inducing hypothermia in a patient using medical saline containing about 0.45% to about 7.5% solute. Create slurry on demand. For example, the sterile ice slurry produced can be used to protect patients during sudden death, heart attack, stroke, heat stroke, septic shock, or other medical conditions where uncontrolled hemorrhagic shock is a problem. Therefore, therapeutic hypothermia can be induced quickly.

  As shown in FIGS. 6A-B, the two-phase coolant generation system includes several major components that are assembled into the slurry generator 200. An exploded view of an example of a suitable assembly configuration is shown. FIG. 6B shows the configuration shown in FIG. 6A rotated 90 degrees. The illustration includes a housing 220, a heat exchanger 240, a drive shaft 260, an ice scraper blade 280, an internal disk 300, a mixing blade 320, a mixing vessel 340, and a mixing vessel housing 360. The assembly may further include a gasket and connector, such as a screw or snap fit (not shown).

  In some aspects, the system includes a housing 220 configured to house the major components of the two-phase coolant generation system. The housing can be composed of any suitable material such as metal, plastic, rubber, silica, polymer, glass, wood, and the like. The housing can be insulated. Plastic is preferred as the material. As shown in FIG. 7, the housing can include a bore 222 for housing the components of the two-phase coolant generation system. FIG. 7A shows one exemplary outer configuration of the housing. FIG. 7B shows a cutaway view of the housing and shows an example of another component form of the slurry generation system in the housing. This component can be fastened to the housing by any means suitable in the art. Preferably, the components are reversibly assembled so that they can be periodically cleaned and / or sterilized.

  The housing can also include openings, such as coolant inlet 226 and coolant outlet 224, as well as fluid inlet 230 and ice slurry outlet 228 to be ice components of the ice slurry that can be frozen. Used. The opening can optionally include a connector configured to couple the housing to a fluid container, a slurry storage container, piping for slurry delivery, and other components of the system. The connector may be any connector suitable in the art for its intended use.

  Preferably, the housing includes a heat exchanger 240. The heat exchanger has a length L and a diameter D (FIG. 7B). In some preferred embodiments, the heat exchanger includes one or more tubes, preferably concentric tubes, which separate the coolant from the fluid containing the two-phase coolant.

  As shown in FIG. 8, the heat exchanger can include one tube. The tube has a bore 244 through which a fluid containing a two-phase coolant can flow, and the ice phase of the resulting slurry is formed on the sidewall 246 of the bore. The coolant flows between the housing 220 and the heat exchanger tube 240. The heat exchanger tubes range in length from about 1 inch to about 24 inches (1 inch≈2.54 cm), although shorter or longer tubes may be used. Preferably, the length of the tube is from about 1 inch to about 6 inches. The inner tube ranges in diameter from about 0.25 inches to about 2 inches. Preferably, the inner tube has a diameter of about 0.5 inches. The outer tube ranges in diameter from about 0.5 inches to about 2.5 inches. Preferably, the outer tube diameter is about 0.8 inches. In one non-limiting example of a single heat exchanger tube, the tube length L is about 6 inches and the diameter D is about 0.75 inches.

  The heat exchanger tubes can be made from any material suitable in the art, the material chosen depending on the application in which the system is used. The heat exchanger tubes can be constructed from metals such as stainless steel, platinum, or titanium. Preferably, the heat exchanger material is stainless steel. The inner and outer tubes may be made of the same material or different materials. The outer tube can be composed of stainless steel, platinum, titanium, nylon, polycarbonate, Teflon®, or Tygon®. Preferably, the material is insulative and sterilizable, such as polycarbonate.

  The heat exchanger tubes are housed in the housing, and the heat exchanger tube walls are in direct contact with coolant flowing through the housing bore or otherwise present. The tube is fastened to the housing or floats loosely in the housing. The coolant cools the heat exchanger tubes to a temperature sufficient to freeze the fluid that contacts the sidewalls of the heat exchanger tubes. Furthermore, the cooling of the fluid can result in freezing of the fluid without direct contact with the side walls of the heat exchanger tubes. The coolant can be any coolant suitable in the art to freeze the fluid in question. Non-limiting examples of coolants include dry ice-alcohol slurry, compressed refrigeration gas such as Freon and ammonia, polyethylene glycol, polypropylene glycol, water, sodium chloride brine or potassium formate salt water or dextrose solution such as dextrose drop water, Alcohol, etc.

  Preferably, the heat exchanger tubes include a drive shaft 260, such as that shown in FIG. The drive shaft includes a shaft 262 that rotates within the inner tube of the heat exchanger. The drive shaft can further include one or more scraper blade holders 264 that reversibly fasten one or more scraper blades to the drive shaft. The drive shaft can further include one or more channels 266 to aid fluid flow and transport and to allow the forming ice slurry to pass through the heat exchanger. The channel may be cut into the tip of the drive shaft at an angle that produces a pulsating flow through the downstream components of the slurry generation assembly. One problem with producing this type of coolant is that the ice particles tend to agglomerate and harden, making it impossible to pump the slurry. A major obstacle in the flow path of the slurry becomes the stagnation point of the flow, which is where the ice particles agglomerate. The pulsating flow can reduce and even eliminate the concentration of ice particles likely to occur in dendritic ice crystals. In addition, the drive shaft provides a suitable means for coupling the mixing blade 268.

  The drive shaft may be fastened to the heat exchanger or to the housing. The drive shaft may rotate clockwise, counterclockwise, or a combination thereof. The drive shaft may rotate at any speed suitable in the art. The rotational speed of the drive shaft is related to the number of blades that scrape the ice. For example, analysis of the water freezing process has shown that it is preferable to scrape the ice interface about every 1/30 second to about 1/5 second. In some preferred embodiments, the ice interface is scraped every 1/20 second. Therefore, it is preferable that the drive shaft with one scraping blade rotates at about 1200 rpm. The drive shaft with two scraping blades preferably rotates at about 600 rpm. The drive shaft with three scraping blades preferably rotates at about 400 rpm. The drive shaft with four scraping blades preferably rotates at about 300 rpm. This relationship between the number of scraping blades and the drive shaft rpm follows all numbers of scraping blades. In a further preferred embodiment, the drive shaft rotates from about 0.0001 to about 200 rpm. The rotation can be performed by any means appropriate in the art, including the use of a motor. In some embodiments, a suitably powered motor with battery or AC power can be attached to the proximal end of the drive shaft 262. In another embodiment, a turbine blade may be attached to the proximal end of drive shaft 262. This drive shaft can be powered by a pump used to pump fluid into the device.

  As shown in FIG. 10, the drive shaft can include one or more scraper blades. The scraper blade is configured to remove formed ice from the sidewall of the inner tube. Each scraper blade can optionally include one or more openings 282. The opening allows scraped ice particles to pass freely through the scraper blade. Opening sizes range from about 1/16 "to about 1/2" (0.16cm-1.27cm) wide and from about 1/4 "to about 8" (0.64cm-20.32cm) long is there. Preferably, the opening is about 1/8 inch (0.07 cm) wide and about 3/4 inch (1.91 cm) long.

  Free passage through the scraper blade helps to ensure the uniformity of the resulting slurry. The scraper blade can be made from any material suitable in the art, such as metal, plastic, rubber, glass, polymer, silica and the like. The end of the scraper blade that contacts the ice formed on the side wall of the inner tube can be tapered. The scraper blade can be in the form of an auger. In the spiral cut configuration, the scraper blade serves at least two purposes. In some embodiments, the helical scraper blade helps to scrape ice from the heat exchange interface and also helps transport the brine slurry through the device. The spiral-cut embodiment has the advantage that fewer pumps are required and less power is required to operate. The number of spiral scraper blades can be from one to many. The number of blades is determined by various variables such as the desired slurry flow rate, helical parameters (lead, lead angle, and average helical diameter), and the desired RPM of the motor.

  In some aspects, the slurry generation assembly includes an inner disk 300 as shown in FIGS. 11A-C. Figures AC show the internal disk viewed at different angles. The inner disk can hold the bearing near the end of the drive shaft. The inner disk has one or more openings 302 that allow the generated ice-salt slurry to pass through the disk and proceed to the next component of the device. In addition, the disc includes two faces for compressive forces that seal the device together, including the tip of the heat exchanger and the proximal end of the mixing vessel. Optionally, gaskets can be used between the tip of the heat exchanger and the disk and between the proximal end of the mixing vessel and the disk.

  In some aspects, the slurry generation assembly includes a mixing blade 320. One non-limiting example of a mixing blade is shown in FIGS. 12A-C. 12A shows a side view of the mixing blade, FIG. 12B shows a top view of the mixing blade, and FIG. 12C shows a three-dimensional perspective view of the entire mixing blade. The blade is configured to mix and / or finely homogenize the ice slurry produced in the heat exchanger (which becomes a dendritic ice slurry) and high-concentration brine. The blade shape is designed to create turbulent (disordered) mixing of the slurry and concentrated saline. In some embodiments, the mixing blade is configured to extrude the slurry radially and instead bias the concentrated brine to a more central area.

  The ice particles that initially form the ice slurry generally contain sharp dendritic edges. The shape of the ice formed may prevent or even make pumping of the slurry into the tube, for example for delivery to the patient. Smoothing the shape of the ice particles can be either a primary ice formation process or a secondary smoothing process, thereby solving the problem of transporting ice slurries composed of dendritic ice crystals. The secondary process described above can be added to many commercially available slush generators, making the slurry easy to pump or drink. Non-limiting examples of soft ice generators currently on the market: ORS-1075HS HUSH-SLUSH® (OR Solutions, Inc., Chantilly, VA) system, SLURPEE® machine (7-Eleven), There are thrusty machines, frozen alcoholic beverage machines, and building cooling systems that use two-phase coolant.

  In addition, smoothing the shape of the ice particles can be achieved by controlled heating of the slurry, by adding an effective amount of concentrated saline to the ice slurry, or by adding an effective amount of non-frozen liquid. Applying a small amount of heat to the slurry can be done by heat flux or liquid flux while stirring the slurry, leading to the formation of smooth ice particles. The amount of heating required depends on, for example, the desired slurry flow rate. Heat can be applied by maintaining the wall temperature above the average temperature of the slurry. Non-limiting wall temperatures range from about 0 ° C to about 40 ° C, with the lower ranges of 0-4 ° C and 30-40 ° C being preferred. Two preferred temperature ranges correspond to different heating areas, with the larger heating area corresponding to the lower wall temperature.

  High-concentration saline includes about 3.5%, 5%, and 7.5% medical saline that is commercially available and contains about 1 to about 10 percent solute. Brine includes one or more of the following non-limiting solutes, which are preferably pharmaceutically acceptable or physiological salts or sugars such as, but not limited to, sodium chloride, sodium lactate, potassium phosphate Calcium chloride, potassium chloride, sodium phosphate, potassium diphosphate, potassium formate, glucose, and dextrose.

  Controlled heating of the ice slurry and / or addition of high concentration brine to the ice slurry can be performed on any component of the slurry generation assembly. In one preferred embodiment, the assembly includes a dedicated component for smoothing ice particles, such as a mixing vessel. The mixing vessel can be configured in any shape and size suitable for the field. In some highly preferred embodiments, the mixing vessel is conical as shown in FIG.

  The mixing vessel 340 includes an inlet 342 for ice slurry formed with a heat exchanger that passes through an internal disk. The mixing container also includes an outlet 344 for draining the purified slurry, eg, draining to be administered to a patient. In some embodiments, the container can include one or more inlets 346 that allow a high concentration of salt water to be added to the container lumen. The mixing container includes a mixing blade. In some embodiments, the container can be heated to smooth the ice particles. Non-limiting examples of methods for heating the mixing vessel include incorporating a resistance heating device into the mixing vessel wall, flowing warm fluid around the outside of the mixing vessel wall, or forming the mixing vessel wall with a heat pipe. For example, the wall temperature set higher than the slurry temperature may be realized by a heat pipe. The container can be made of any material suitable in the art, such as metal, plastic, rubber, silica, polymer, glass, etc., and is selectively insulated.

  In some embodiments, the slurry generation assembly can include a mixing vessel housing 360. An example of a container housing configured to receive a mixing conical container is shown in FIG. The container housing component is configured to hold the components of the assembly at the distal end of the inner disk, is reversibly fastened to the main housing of the assembly, and seals all the various different compartments together. Give compression to hold together. In some preferred embodiments, the container housing includes one or more openings 362 that allow the concentrated slurry to enter the mixing container through the container housing. In some preferred embodiments, the container housing includes one or more outlets 364 for discharging the slurry produced from the slurry production assembly. In some highly preferred embodiments, the outlet includes a fitting 366 for connecting to a tube, such as an intravenous tube, for administering the slurry to the patient. Any mounting component suitable in the art can be used, such as an IV luer connector. Non-limiting examples of other possible connectors include cooling of standard lead tube connectors, lasers, guns, cannons, and electromagnetic generators used in building cooling, cooling of perishable items, or fire fighting sprinkler systems. Suitable for connectors, suitable for fire hose and water gun, suitable for personal cooling system such as cooling cap, cooling vest or personal mist generation system, suitable for staff mist generation system (sports team bench) Of structural elements under extreme conditions, such as connectors that are compatible with cryogenic spasticity systems, connectors that are compatible with smelter cooling, building frame cooling in the event of a fire, or spacecraft protection when reentering the atmosphere with a damaged heat shield. Connector compatible with cooling, connector compatible with air cleaning system, improved toxic gas collection Connectors suitable for transport, connectors suitable for minimally invasive surgical instruments used for organ preservation during prolonged surgery, connectors suitable for storage tank deposits, gastrointestinal tract, lung irrigation tubing, or nasopharynx, oral cavity, For connectors that are compatible with local medical cooling such as slurry release into the ear, anus, or vaginal cavity, connectors that are compatible with slurry release into the abdominal cavity or intrathoracic space, or other physiological spaces or areas There are suitable connectors, etc.

  In some aspects, a slurry production system as described and exemplified herein includes four volumes. The first volume contains low-concentration brine and is cooled to form ice in the brine. In some preferred embodiments, the slurry contains from about 10 to about 90% ice, although higher or lower percentages can be produced, depending inter alia on the specific needs of the researcher. More preferably, the slurry contains about 20 to about 80% ice, more preferably about 30 to about 70% ice, more preferably about 40 to about 60% ice, and more preferably about Contains 50 to about 60% ice.

  The second volume surrounds the first volume and is separated by the structure of the heat exchanger. This second volume is the part where the coolant is recirculated. Preferably, the coolant and brine create opposite flow heat exchangers with opposite flow directions. Coolant can be circulated through the phase change refrigeration unit where heat is removed. The refrigeration unit is preferably non-electrical, but may be an electrical unit.

  The third volume is where the ice slurry generated from the heat exchanger is heated or mixed with highly concentrated brine. Controlled heating of the ice particles or mixing with additional salt will smooth the ice particles and allow the slurry to be pumped. The mixing blade may be in the third volume.

  The fourth volume surrounds the third volume and is where highly concentrated brine is introduced into the assembly. This volume is configured to allow high-concentration brine to flow freely to all surfaces of the mixing vessel. This helps in uniform mixing and reduces resistance as the ice slurry flows through the vessel. The finished ice slurry exits from the end of the container. In some embodiments, the slurry is pumped through one or more components of the assembly and / or pumped through a tube for administration to a patient.

  In the counterflow heat exchanger configuration, the coolant flow rate and the salt water flow rate are physically related based on the desired porosity of ice. The heat transfer equation is further complicated by the temperature of the heat exchanger wall changing as a function of distance through the device. In addition, energy may be required to pump the coolant liquid. To optimize the configuration and operation of the slurry production system, an annular heat pipe can be used as the heat exchanger for the system. Thus, in some preferred embodiments, the heat exchanger is a heat pipe, preferably an annular heat pipe.

  In an exemplary embodiment, the heat pipe is essentially a self-contained surface tension driven heat pipe. When the temperature gradient is across the heat pipe, heat is transferred across the heat pipe by conduction and convection, enabling a heat transfer that is 100 times greater than conduction alone. Another advantage of heat pipe technology is that the heat pipe can be adjusted to have the desired evaporation or condensation temperature by controlling the internal pressure during manufacture. This makes it possible to obtain a constant temperature surface set without any other control or feedback. Thus, heat pipes have the additional advantage of reducing or eliminating the need to pump coolant, and the advantage of having a constant wall temperature heat exchanger surface. This makes it possible to produce smaller and mobile slurry generation systems and devices, and systems and devices that require fewer pumps and therefore require less power to operate.

  An example of a heat pipe heat exchanger configuration is shown in FIG. This is a cross-sectional view. The heat pipe is preferably an annulus, which is cut in half along the central axis in this figure. In the illustrated form, the liquid in the heat pipe condenses on the coolant side and is carried towards the salt water side where the coolant evaporates. The evaporation temperature is kept between about 0 ° C and about -20 ° C. The coolant may be a compressed gas such as liquid nitrogen or an alcohol mixed with dry ice. The heat pipe gives a uniform temperature on the salt water side even if there is a temperature gradient on the coolant side. The coolant can be contained in a second large annular body that houses the heat pipe.

  FIG. 16 shows a variation of the system shown in FIG. In the cross-sectional view of the system shown in FIG. 16, the heat pipe includes an annulus cut in half along the central axis. In this form, the evaporation side of the heat pipe 400 is close to the heater 402. The condensation side of the heat pipe is close to the slurry side. The condensing liquid heats the slurry and melts the ice. The measurement method described above can be used. Condensation temperatures range from about 0 ° C to about 60 ° C.

  Ice slurry generation can be optimized by nucleating ice from supercooled brine outside the primary heat exchanger. For example, generally when a slurry is generated inside a heat exchanger, a nucleation event occurs in a supercooled solution, but this event is not continuous. This means that the ice formed must be obtained primarily by scraping from the surface of the heat exchanger, not from the ice produced by nucleation continuously in solution. In the present invention, the supercooled state is stabilized and ice is nucleated by the disturbance. When ice is produced in the heat exchanger, it is advantageous to make the ice outside the primary heat exchanger, as maintenance of the heat exchanger is difficult and efficiency is reduced. That is, in some embodiments, the present invention provides a system for generating ice from a supercooled solution (a liquid solution cooled to a temperature below the freezing point of the solution), for example, by creating a disturbance in the solution flow. I will provide a. Such disturbances can be created using ultrasound, roughness changes, turbulence changes, and the like. Ice nucleation often occurs easily at existing interfaces. This is because the surface enables particle nucleation by lowering the surface energy and lowering the free energy barrier, and changes in the contact angle between phases affect the surface energy.

  In some aspects, the slurry generation system is configured as shown in FIG. For example, the system 500 includes at least one heat exchanger. The primary cooler 502 can be used to supercool the solution 504 without inducing ice nucleation. A primary cooler is, for example, a counter-flow surface scraping heat exchanger (as described and exemplified herein), an annular heat pipe, or any refrigeration technology that can cool brine below its freezing point. It's okay.

  Ice nucleation can be induced in a supercooled solution, for example by perturbing a steady stream. The stable flow may be laminar or turbulent. Flow perturbation 506 may include ultrasound, flow stagnation point, introduction of seed ice pieces, use of geometries that generate bubbles, vortices or vortices (eg, pyramid shapes), physical object angles to adjust wetting ( It can be induced by methods such as adjusting the contact angle), changing the material of the physical object to adjust the wetting, or changing the momentum of the fluid flow (changing the fluid flow diameter), other perturbation means, or combinations of the above. These perturbations can generate inhomogeneous nucleation in the solution to form an ice slurry 508. The disturbance is in an ice nucleation chamber 510 that is spatially separated from the primary cooler, eg, coupled to the primary cooler. The total ice ratio as well as the particle size can be controlled by continuously removing heat from the slurry using a selective secondary cooler 512 after the start of nucleation.

  In some aspects, the flow turbulence is a local pressure fluctuation, such as a local pressure fluctuation due to impingement of a supercooled fluid jet or due to ultrasound.

  A supercooled fluid jet impinging on a fluid bed of supercooled fluid can induce heterogeneous nucleation. In this embodiment, pressure fluctuations due to jet / droplet collisions in the fluid bed are thought to cause local fluctuations in the equilibrium freezing temperature leading to inhomogeneous nucleation.

  The probability that impinging jets will induce inhomogeneous ice nucleation can be increased by introducing bubbles on the surface of the fluid body. While the bubbles are preferably stable in the fluid bed, they impose practical limits on the characteristic length scale of the bubbles. In this embodiment, ice crystallization begins at the bubble interface while there are bubbles under the impinging supercooled fluid jet. In addition, the collapse of bubbles under the pressure of the impinging jet can cause local fluctuations in the equilibrium freezing temperature, which can lead to inhomogeneous ice nucleation. This mechanism may also apply to nucleation of ice crystals using ultrasound.

  Ultrasound is believed to induce ice crystal formation by the collapse of cavitation bubbles. When the microbubbles collapse, the local pressure gradient can be greater than 1 GPa. This local high pressure field can result in locally high equilibrium freezing temperatures and can lead to ice nucleation. Furthermore, there is a region of relative negative pressure in the period after the bubble collapse, leading to a local increase in the equilibrium freezing temperature. There is also evidence of secondary nucleation processes as a result of bubble motion induced by buoyancy. However, since the time scale is too long, secondary ice nucleation effects are not explained by the collapse of the cavitation bubble. In general, nucleation of ice crystals by ultrasonic waves strongly depends on the amount of gas dissolved in the liquid, and requires about 5 degrees of supercooling at an absolute temperature. In the degassed liquid, the propensity to form ice crystals by the ultrasonic pulse is significantly reduced. This view is described, for example, by Zhang et al., “Ultrasonic-induced bubble nucleation in water containing bubbles”, Ultrasonics Sonochemistry 10 (2003) 71-76; and Ohsaka et al., “Single Dynamic nucleation of ice induced by stable cavitation bubbles ", Appl. Phys. Lett. 73, 129 (1998). These documents are incorporated herein by reference.

  In some embodiments, one or more ice crystals can be used to induce ice nucleation. Ice can be used in at least two ways to induce spontaneous nucleation of the supercooled liquid. The first is the creation of a stagnation point using ice blocks. The stagnation point itself can sufficiently induce heterogeneous nucleation. Forming an ice mass has the additional advantage that the ice mass is cooler than the supercooled liquid and therefore can absorb heat from the supercooled liquid while preserving the structure of the ice crystals. In addition, ice seed crystals can be added. Inhomogeneous nucleation is a stochastic process, so the number of seed crystals required is inversely proportional to the degree of supercooling. Therefore, the higher the degree of supercooling, the fewer ice seed particles are needed to induce heterogeneous nucleation. The crystal structure of ice blocks or seed crystal particles can be the basis for crystallization of the supercooled liquid. By embedding stable ice crystals in the supercooled solution, the radius condition required to create ice nuclei from the solution is relaxed. This is because ice crystal growth can start from a surface that has already been formed. The ice crystals may be from any material including dry ice.

  In some embodiments, stagnation points, vortex or vortex shedding, flow separation, or interface placement in solution flow can be used to aid ice nucleation. For example, vortex or vortex shedding, flow separation, or a sharp contact angle interface can be generated by one or more trips. The trip may be in any suitable form, including but not limited to the form shown in FIG.

  FIG. 22A shows a post design trip. The post trip creates a fluid stagnation point in the center and provides an interface that increases flow velocity by reducing the available cross-section and / or lowers the free energy barrier. The post may have any width or diameter suitable to affect flow velocity, ice particle size, ice particle shape, and total production of ice slurry. Preferably, the post is located in the middle of the ice flow tube so that the cooled solution and the formed ice slurry can flow between the side wall of the ice flow tube and the outer surface of the post. The length of the post can be any suitable length and in some preferred embodiments spans the entire length of the tube carrying the supercooled effluent from the primary cooler. Post trip configuration can be optimized according to application needs, eg changing the diameter of the post, changing the diameter of the post as a function of length (ie conical), changing the material from which the post is made (Eg, plastic, metal, foam, etc.), changing the surface properties of the post (eg, rough or smooth), changing the length of the post (eg, thin / disc-like or very long), tip Can be optimized by changing the characteristics (rounding, flattening, slicing at an angle).

  FIG. 22B shows a cross wire design trip. Cross-wires can create flow disturbances with insignificant stagnation points, create local flow changes by vortex or vortex shedding, and / or provide an interface to lower the free energy barrier. it can. The main change in flow occurs at the center of the flow where all wires cross. There is a maximum stagnation point here, but also because many wires intersect, many surfaces and crevices, and because of the increased interaction at the contact angle, low surface energy is created to aid nucleation. The cross-wire trip configuration can be optimized according to the needs of the application, for example by changing the number of wires, changing the diameter of the wires by using round wires or square wires (thick wires are stagnation points) Change the cross position by changing the material from which the wire is made (stainless steel, ceramic, plastic, etc.), by changing the surface properties (rough or smooth) by elongating the length of the tube Can be optimized by using blades that are arranged in a similar pattern (not at the center but at the periphery) or instead of wires.

  FIG. 22C shows a tooth disign trip. Teeth create a peripheral stagnation point and provide an interface that causes changes in local flow and / or lowers the free energy barrier due to the vortex or vortex shedding. When using teeth, the main change in flow occurs in the peripheral part of the flow. Teeth design and trip configuration can be optimized according to application needs, for example, changing the number of teeth, changing the tooth edges (round or straight), making the teeth three-dimensional, for example pyramidal, Change angle (can be bent towards or away from flow), change overall angle (eg set to 45 degrees), change tooth surface properties (rough or smooth), teeth or trip Changing the overall material (stainless steel, ceramic, plastic, etc.), changing the diameter of the opening through which the fluid flows, changing the radial height of the teeth, elongating the length of the tube, or simplifying the shape of the post It can be optimized such as by protruding from the side wall of the tube or with vanes extending over the length of the side wall of the tube.

  FIG. 22D illustrates a central tooth design trip with possible design modifications such as round tooth configuration, pointed tooth configuration, and serrated blade configuration. The central tooth, like the post, creates a central stagnation point and provides an interface that causes changes in local flow and / or lowers the free energy barrier due to the vortex or vortex shedding. The central tooth design can be thought of as a fusion of the cross-wire design (Figure 22B) and the post design (Figure 22A) in a way that changes the basic post design to enhance the vortex or swirl emission. . The shape of the central tooth can be optimized according to the needs of the application, e.g. changing the number of teeth, changing the edge of the tooth (round or straight), making the teeth three-dimensional, e.g. forming into a pyramid shape, teeth Change angle (can be bent towards or away from flow), change overall angle (eg set to 45 degrees), change tooth surface properties (rough or smooth), teeth or trip Can be optimized by changing the overall material (stainless steel, ceramic, plastic, etc.), changing the diameter of the trip, or extending the length of the tube into an elongated profile, or shortening the tube to a thinner shape, etc. .

  FIG. 22E shows a sticky sphere trip design. The sticky spheres provide an interface that causes changes in local flow and / or lowers the free energy barrier due to vortices or vortex shedding. The main changes in flow occur at the center of the flow. This trip design is believed to induce turbulence and is associated with the three-dimensional deformation of the cross-wire trip (FIG. 22B). The sticky sphere trip shape can be optimized according to the needs of the application, eg changing the diameter of the sphere, changing the shape of the sphere (sphere, ellipsoid, cube, etc.), number of thorns, length, and The diameter, the nature of the tip of the thorn, the angle protruding from the body to which the thorn is attached, the thorn and / or the material from which the body is attached (stainless steel, ceramic, plastic, etc.) and / or the thorn and / or base It can be optimized by changing the roughness. The simplified sticky sphere-version has the shape of a Bethlehem star.

  FIG. 22F shows a pyramid trip design. Pyramid trips, like the tooth design shown in FIG. 22C, create a flow turbulence with small, insignificant stagnation points, and a change in local flow due to the vortex or vortex shedding, It can also provide an interface that lowers the free energy barrier and increases the amount of ice produced by the length and / or multiple shed points distributed radially. Pyramid trip forms can be optimized according to application needs, eg changing the number of pyramids, pyramid shape (eg tetrahedron), round vs. straight, changing pyramid mounting angle ( For example, in the direction of flow or in the direction opposite to the flow), change the surface properties (rough or smooth), change the material from which the pyramids are made (stainless steel, ceramic, plastic, etc.), in the length direction of the tube or It can be optimized by changing the interval of the pyramids in the circumferential direction of the tube, or providing two or more pyramids at a certain position of the tube.

  FIG. 22G shows a surface roughness trip design. Surface roughness trips create micro-interfaces that create flow turbulence with insignificant stagnation points, change vortices or vortex shedding, and / or reduce free energy barriers I will provide a. Roughness creates a number of faces and crevices on the surface, thereby reducing the surface energy by increasing the interaction with the contact angle and helping nucleation. Surface roughness trip configuration can be optimized according to application needs, for example, changing the level of roughness (from coarse to fine), increasing or decreasing the degree of roughness as a function of length, It can be optimized by changing the overall length, or changing the material used to make the rough surface.

  FIG. 22H shows a trip configuration with a tooth combination. The tooth profile combination has the synergistic advantage of the tooth design shown in FIGS. 22C and 22D. Trips with tooth profile combinations increase the production of slurry by having multiple vortices or vortex shedding points distributed in the length and radial direction of the flow tube. This combination can be optimized according to the needs of the application, for example, the design of each tooth described above can be optimized. Furthermore, the trip can be optimized using different combinations of tooth designs, such as a combination of round and pointed teeth.

  FIG. 22I shows a trip configuration of a dimpled tube. A dimpled tube trip can be either a small insignificant stagnation point (if it is a hollow structure as shown) or a solid (as in the post design shown in FIG. 22A). (If the structure) the central stagnation point can create a flow disturbance, causing flow separation at one or more dimple interfaces (which causes the fluid to move away from the surface of the object), creating vortices and spirals, Provides an interface that lowers the free energy barrier. This trip design can be optimized according to the needs of the application, e.g. changing the number of dimples and the depth of the dimples, elongating the length of the tube into a long profile, changing the surface properties of each dimple (rough or Smooth) and / or can be optimized by changing the material used to make the trip (stainless steel, ceramic, plastic, etc.).

  FIG. 22J shows a tripped configuration of a bladed cone. A winged cone trip changes the local flow by vortices or vortex shedding and provides an interface that lowers the free energy barrier. The main changes in flow occur at the center of the flow. This trip is a variation of the post design described above that enhances vortex or vortex shedding. The cone can be optimized according to the needs of the application, for example, the length of the cone, the number of vanes, the height of the vanes, the surface properties of the vanes (rough or smooth), and / or to make the cones and / or vanes It can be optimized by changing the materials used.

  Inducing ice nucleation outside the primary cooling system has several advantages. The need to scrape the surface as ice is formed can be reduced or eliminated. However, in some aspects, continuing to use scraping is desirable to reduce the effect of icing on heat transfer rates, and further, system wear, system cost, system weight, and system size. Reduce (without motor). If the problem of icing is eliminated, the overall efficiency of the system is increased. Cooling system modeling is also facilitated because heat transfer is easier to understand physically and mathematically. This also allows ice to be nucleated in a tube having the diameter of an intravenous tube, eliminating the difficulty of moving the flow of particulate material from a large diameter to a small diameter prior to administration to a patient.

  In another aspect of the invention, ice slurry production is optimized by combining the two solutions. The concentration of a solution determines its freezing point by an entropy penalty associated with the freezing process. A solution that is maintained at a temperature below the freezing point is a supercooled solution. Higher concentration solutions can achieve lower temperatures by freezing point depression than lower concentration solutions. It is advantageous to produce ice outside this device, as the scraped surface heat exchanger is less maintainable and efficient when ice is produced in situ.

  That is, a highly concentrated supercooled solution (solution A) is mixed with, for example, cooled water (or a cooled solution having a lower concentration than solution A) (solution B) to create a solution (solution C) having a desired concentration. An ice slurry can be produced by making the temperature below the freezing point of solution C (i.e., already supercooled solution C). This supercooled product, solution C, is described here, for example, by a method of combining two fluids (solution A and solution B) or in a secondary scraped surface heat exchanger just prior to the site utilizing slurry. And ice nucleation can be induced by using the exemplified method. The desired concentration of solution C determines the ratio of combining solution A and solution B, and also determines the freezing point of the product. The freezing point of the product, in combination, determines the temperature required for the two solutions (A and B) that form the product solution C.

  Ice nucleation occurs in a special nucleation region of the system of the present invention. For example, the nucleation region includes one or more stagnation points, one or more vortices or vortex shedding points, or one or more interfaces, such as the trip described and illustrated herein. The nucleation region may be a nucleation chamber configured as shown in FIG.

  Nucleation chamber 600 may be constructed of any suitable material such as plastic, metal, ceramic, wood, etc., and includes at least one tube hole 602 having a width or diameter of D′-1, through which a supercooled saline solution passes. Flow assists in ice nucleation and slurry formation. The chamber includes a space 604 having a width or diameter of D'-3 and a length or depth of D-2, in particular one or more trip holders 606A and 606B, and optionally, for example, length or depth. It is sufficient to accommodate the spacer 618 of D-1. The chamber also includes a space 620 for the O-ring. In some aspects, the back of the chamber can include a drip shoulder 616, which includes an overhang that prevents liquid passing through the chamber from dripping down the back of the chamber. Further falling slurry and / or solution can be collected. However, this drip shoulder can be replaced with another O-ring surface connected to the slurry delivery system.

  In some aspects, the chamber includes an opening 614 that can be used to remove water and / or slurry from the chamber for analysis of concentration, crystal size and shape. In some embodiments, the opening may form a hose fitting connection to assist in removing water with a vacuum. The connection can include a thread groove 628 that matches the thread groove of a commercially available hose fitting. The trip holder shown in detail in FIG. 24 has a width or diameter of D′-2, includes a groove 610 that fits one or more trips, and further inserts fasteners to rotate the trip holder. One or more openings 608 are included to prevent misalignment. For example, a fastener can be attached to the chamber wall or housing opening 612.

  FIG. 24 is another view showing components such as trip holders and spacers that the space (604) shown in FIG. 23 may include. For example, FIG. 24A shows a front view of trip holder 606A. This orientation indicates the opening 608, the location of the groove 610 holding the trip, and the width or diameter D'-1 and D'-3. FIG. 24B is a front view showing the positions of the trip holder 606B and the opening 608. FIG. FIG. 24C is a front view showing a “blank” having a width or diameter of D′-1, which fits into the groove 610 of the trip holder 606A when using a post design trip. FIG. 24D is a cross-sectional view showing trip holders 606A and 606B having a width or diameter of D′-3 (shown in FIGS. 24A and 24B), with a bore 602 and opening 608, and a width or diameter of D ′. The position of the -2 groove 610 is shown. FIG. 24E is a front view showing a spacer having a width or diameter of D′-3 and a tube hole 602 through which the supercooled solution flows. The spacer can be made of any suitable material, and in some preferred embodiments is made of the same material used to make the chamber housing.

  A front view of the ice nucleation chamber is shown in FIG. This figure shows the position of the tube hole 602 through which the supercooled solution flows, the space 620 of the O-ring, the space 604 having a width or diameter of D′-3, and the opening 608. Also shown is an opening 646 for a fastener that fastens a hose attachment port to the front of the chamber as shown in FIG.

  In some embodiments, the chamber is configured to receive a supercooled solution from the primary cooler. For example, the supercooled solution can flow from the cooler through the tube to the nucleation chamber by a fixture, such as a fixture as shown in FIG. A hose fitting can be used to minimize or eliminate the loss of supercooled fluid from the tube and to ensure a smooth transition to the nucleation chamber. One typical hose fitting is shown in FIG. The hose fitting 640 has a tip 642 to which a tube or hose can be reversibly attached and a tube hole 644 that allows the supercooled solution to flow through the fitting into the tube hole of the chamber 602. The hose fitting base 648 includes one or more openings 646 for fasteners that can engage an O-ring on another surface and fasten the hose fitting to the chamber.

  An opening 614 near the back of the chamber for removing ice and / or slurry samples is shown in more detail in FIG. This figure shows an example of a hose fitting having a thread 652 that matches the thread 628 of the chamber. An opening near the back of the chamber may be drilled to allow attachment of a vacuum to separate the nucleated ice from the solution. This opening can be used to determine the ice mass ratio from the increase in solution concentration.

  A front view of the back of the chamber is shown in FIG. The back surface has an opening 602 having a width or diameter of D′-1 for the formed ice slurry to pass out of the nucleation chamber. In addition, there is an opening 654 for attaching a fastener. FIG. 28 shows that the area with the back wall has been removed and that liquid and / or slurry can be collected without running down the back of the nucleation chamber. However, this back surface may also have an optional O-ring space that allows the nucleation chamber to be connected to a slurry delivery device.

  A post design holder is shown in FIG. FIG. 29A shows a front view of a rear view that can be used when using non-post trips. The post design trip holder may have a width or diameter D′-4 corresponding to the diameter of the post trip and may have an opening 656 in which the post trip can be attached. D′-4 may be smaller than D′-1. There is also an opening 654 that aligns with the opening 654 shown in FIG. 28, which allows the fastener to fasten the post design trip holder to the nucleation chamber. FIG. 29B shows a side view of a back configuration that can be used when using a post trip. An opening 656 having a width or diameter of D′-4 for placement of the post and an opening 654 for fastening to the nucleation chamber are shown.

  The system and apparatus for generating the ice slurry preferably includes monitoring instruments that can complete processing and analysis in real time or after operation to confirm failure modes, and have appropriate mechanisms to accommodate the various failure modes. . This system and device has performance criteria defined from calculations and experimental calibrations, and deviations from this criteria can be used to change or control the operation of the device.

  For example, any non-characteristic change in heat flow causes the system to systematically evaluate temperature, rotational speed, and torque individually and / or in combination, and identify the cause of system failure. Then, optionally, this cause is translated to alert the user to deal with the failure.

  The temperature measuring device may be a thermocouple, but is not limited thereto, non-limiting examples of which are K ′, J, T, and E type thermal resistance devices (RTD ′s) or infrared instruments. The rotational torque can be measured using various methods, for example, using a moment arm, a slip ring, a rotational transformer method, and the like. Various sensing methods such as a rotational speed sensor or an angular displacement sensor can be used, and can be used in various ranges. The instrument for measuring rotational speed and rotational torque may be in the form of a single sensor or with various sensor ranges. Such instruments are known in the art. All measurement results can be sent to a computer for data acquisition and analysis.

  The ice slurry generation system and apparatus preferably has a target heat transfer coefficient, which can be changed by changing the mass flow rate of the system. That is, optimal ice slurry generation has a target heat transfer coefficient that, if not met, indicates a system failure.

  The system can be monitored by analyzing the temperature of the coolant and ice slurry (product) measured at the inlet, outlet, or both, or elsewhere, where the coolant or product temperature can be This monitoring initiates a failure mode if it rises above or below a range or optimum range. This failure mode includes coordination of the system's operation to bring the coolant and product temperatures to the proper ranges.

  The rate of temperature change is also useful as an indicator of failure mode. Changes in the temperature of the coolant and ice slurry product cause changes in the heat transfer coefficient.

  Another data point that is monitored to optimize the operation of the slurry production system is the adhering ice coming out of the heat exchanger. Changes in the ice removal operation result in changes in the heat transfer coefficient. Furthermore, the resulting slurry can be monitored individually or in combination based on at least three properties: (1) ice mass concentration; (2) ice particle size; and (3) ice particle shape. It is. These three properties can determine the rheological properties of the slurry, the melting temperature range, and the required pump power. When these properties fluctuate outside of an acceptable optimum range, a series of adjustments designed to pull these properties of the ice slurry back into acceptable ranges can be initiated.

  The present invention also provides a method of producing an ice slurry using the ice slurry production system described and exemplified herein. In some detailed aspects, the method comprises contacting a fluid, such as low-concentration brine, with a heat exchanger for a time sufficient to freeze a portion of the fluid to form an ice slurry, and then Mixing high-concentration brine with this ice slurry. The heat exchanger may include two concentric tubes or may be a heat pipe such as an annular heat pipe. High concentration brine smoothes the ice crystals formed and allows the slurry to be pumped. In another aspect, the method includes contacting a fluid, such as low concentration brine, with a heat exchanger for a time sufficient to freeze a portion of the fluid to form an ice slurry, and then the ice slurry. In contact with a heat source for a time sufficient to smooth the ice crystals in the slurry. Using these methods, ice slurries can be generated at any scale, on a small or large scale, for example, for administration to a patient, for fire suppression, or for crowd control .

  The present invention also provides a method of using a two-phase coolant, such as an ice slurry produced by the ice slurry production system and apparatus of the present invention. The ice slurry can be used to cool or maintain a certain temperature in any application where it is desired to maintain a low temperature or temperature.

  In a highly preferred embodiment, the present invention is a method of inducing or maintaining hypothermia in a subject, such as an ice slurry produced by the inventive ice slurry generation system and method described and exemplified herein. A method comprising administering to a subject in need a pharmaceutically acceptable ice slurry. This ice slurry is administered to the subject in an amount effective to induce or maintain hypothermia. The effective amount will depend on various factors. Non-limiting examples of such factors include subject species, height, weight, age, symptoms to be treated, and the like. Administration can proceed by any means suitable for the particular application in which the coolant is used. For example, the coolant can be administered intravenously, intramuscularly, topically, orally, intranasally, into the anus, vagina, abdominal cavity or thoracic space, into other physiological spaces or regions, and the like. Intravenous administration is highly preferred.

  These methods can be used on any subject. Preferably, these methods are used for mammals such as horses, cows, pigs, dogs, cats, rabbits, rats, hamsters, and mice. These methods are preferably used beneficially for humans.

  The hypothermia state may be systemic, i.e., the hypothermia state may be induced and / or maintained throughout the subject. Alternatively, the hypothermia can be directed to a specific part (s) of the body, such as a specific organ, appendage, cavity, space, or region.

  A method of rapidly cooling perishable articles or maintaining a low temperature is also provided. Such methods generally include generating an ice slurry using the ice slurry generation systems, apparatus, and methods described and illustrated herein, and exposing perishable articles to the ice slurry. . Non-limiting examples of perishable goods include foods such as meat, fish, agricultural products, milk and dairy products, confectionery, beverages, etc .; pharmaceuticals; vitamins; minerals; volatile chemicals; radionuclides; nucleic acids, polypeptides, lipids, etc. Biomolecules, cells, tissues, organs, and biological fluids such as blood, serum, urine, saliva, sweat, and milk.

  A method of rapidly cooling a device that generates heat, such as a weapon, is also provided. The method includes generating an ice slurry using the ice slurry generation system, apparatus, and method described and illustrated herein, and exposing a weapon or component thereof to the ice slurry. A weapon or part of a weapon, such as a magazine, can be cooled using the method of the present invention. Non-limiting examples of suitable weapons include guns, cannons, and electromagnetic pulse generators. Laser weapons can also be cooled according to the method of the present invention. The weapon may be held by hand or attached to equipment such as an airplane, helicopter, or vehicle.

  The following examples serve to illustrate representative embodiments of the present invention in detail. They are for purposes of illustration and description and are not intended to limit the invention.

On-demand production of brine ice slurry

  In the prophetic desk embodiment, an apparatus for on-demand production of particulate two-phase (solid and fluid) coolant is provided. The device includes two fluid containers, which may be separate or concentric. One container is pressurized and the other is not pressurized. This apparatus is used to produce a uniform and homogenized brine ice slurry.

  The container is filled with water, which may contain different concentrations of salt, surfactant, and / or emulsifier. The container is pressurized to a high enough level to induce an instantaneous expansion of the liquid as it is released from the container. The pressurized container is not completely filled with fluid, leaving a large volume on the order of about 50% for the gas phase. The pressurized container and its contents are cooled to a temperature below the freezing point of the fluid at atmospheric pressure.

  A special nozzle can be attached to the end of the pressurized container. As fluid is forced out of its container, the nozzle generates a fine mist of fluid. Since the temperature is kept below the atmospheric freezing point, the fluid spontaneously changes to a solid phase (eg, freezes) when the pressure is released. The formed ice crystals are treated with a homogenizer where they are mixed with the carrier fluid discharged from the second tank. Homogenization homogenization ensures adjustable ice particle size and chemical smoothness.

  The second container is filled with a fluid that matches the solidified fluid from the first container to form the desired ice slurry. For example, the second container contains water, salt, surfactant, and other emulsifiers. As described above, the second container and its contents are cooled to a temperature lower than the freezing point of the fluid from the container 1 at atmospheric pressure. However, since the fluid from the second container is not pressurized, it remains in the fluid phase even at low temperatures.

  The cooled fluid from the second container is then pumped to the homogenizer and mixed with the ice particles generated from the first container. This fluid is thus used as a carrier fluid for delivering particulate ice to a desired location and application for a desired purpose.

  There may be a pressure connection between the homogenizer outlet and the second vessel. In this case, the excess pressure from the first vessel used to produce the freezing point depression is used after discharge to pump fluid from the second vessel to the homogenizer. A schematic diagram is shown in FIG.

Low power generation of large or small amount of on-demand brine ice slurry

  In this desktop embodiment, an apparatus for on-demand production of large or small quantities of particulate biphasic (solid and fluid) coolant is provided. This device contains a large version of the device described above, as well as a large amount of primary coolant, ie compressed gas or dry ice. The main difference between Example 1 and Example 2 is the supply of slurry that does not require power.

  If power is not available and the use of the two-phase coolant described above is constrained, the power constraints can be overcome using the devices and methods described herein. In this embodiment shown in FIG. 5, one of the slurry generators described herein has been scaled to an effective size for a particular cooling task. In addition, an appropriate amount of primary coolant can be utilized. The primary coolant is pumped to a coolant heat exchanger where the secondary coolant is cooled to a similar or slightly warmer temperature. The secondary coolant is pumped or carried to the slurry generator. In this slurry generator, the secondary coolant cools the brine to its freezing point. Ice is scraped from the surface of the heat exchanger and the ice nucleates in a large volume of liquid. The size of the ice particles is controlled by mixing with an ice scraper blade. Brine and slurry are pumped through the slurry generator and delivered by means suitable for the task.

Two-phase (solid-liquid) coolant quality

  In this desktop embodiment, an in-line system is proposed that ensures the quality of a two-phase (solid-fluid) coolant delivery system, preferably just prior to the field of coolant application. This system is intended to address the problem of changing the quality of the coolant due to melting of the solid phase during the transfer from slurry generation to the site of action.

  This device consists of a tube with known heat transfer characteristics, and a series of heat flux sensors and temperature sensors are embedded in place along the length of the tube. The environment outside the tube is kept at a known temperature. An aqueous ice slurry passes through the tube at a predetermined volumetric flow rate, and heat flux and temperature are measured as a function of the distance that the coolant travels down the tube. Ice porosity is calculated by measuring the total amount of heat entering the coolant slurry. Ice particle size is related to the time taken to transfer heat. These calculations are performed by a computer connected to a series of sensors.

The calculation of the ice porosity is performed as follows. Inside the tube, the fluid is well mixed as a function of the tube design, and the temperature inside the tube stays very close to the freezing point of the liquid until all ice melts. Thus, the heat flux is mainly spent on melting ice. Once the ice melts, the temperature of the liquid begins to rise, which is detected by a temperature sensor. Thus, based on the location of the initial temperature rise of the tube fluid, the measured heat flux as a function of tube length, and the volumetric flow rate, the ice percentage is estimated using a relationship such as Equation 1:
△ Q _slurry = m _slurry C △ T +% _ice m _slurry λ _ice
Where _{ΔQ slurry} is the heat energy obtained from the heater, m _slurry is the mass of the slurry, C is the heat capacity of the liquid phase of the slurry, ΔT is the temperature change of the slurry,% _ice is the ice percentage, and λ _ice is the liquid from ice Is the latent heat of phase change.

The average particle size is obtained from an empirically derived relationship. The heat transfer equation (Equation 2) describing how to measure the average particle size is as follows:
Q (・) = hA △ T
Where Q (•) is the heat entering the slurry in watts (heat flow), h is the convective heat transfer coefficient expressed in W / m ² K units, and ΔT is the temperature of the inner tube wall and the mass fluid Is the temperature difference between. The coefficient h is a function of the volumetric flow rate of the fluid, the physical properties of the fluid, and the size and distribution of the ice particles in the slurry. The value of h is expected to increase as the average particle size decreases with a constant ice percentage. As the particle size decreases, the number of particles increases, similar to the interfacial area available for phase change from solid to liquid assuming a constant volume. An example of the expected measurement difference under these conditions is shown in FIG.

Construction of heat exchanger and formation of ice slurry

General equipment characteristics: A counter-flow surface scraping heat exchanger similar to that shown in FIG. 6 was constructed and used to produce an ice slurry. This apparatus had a heat exchange surface area of 0.011 m ² , an annular gap of 4.94 mm, and 8 scraper blades.

  The primary coolant was 70% or 46% potassium formate. The primary coolant was cooled in a separate heat exchanger loop comprised of a copper coil immersed in a dry ice / propanol mixture. The dry ice / propanol mixture creates a uniform -70 ° C soot, through which potassium formate passes. Potassium formate entered the countercurrent heat exchanger at a temperature below the freezing point of the product. In this case, the product is 10% NaCl (10% saline) or 1% NaCl (1% saline) by weight.

  All exposed tubes were insulated. The ranges of mass flow rates for the coolant and product were (respectively) as follows: 0.011-0.002 [kg / sec] and 0.006-0.001 [kg / sec]. In general, the product entered the countercurrent heat exchanger at room temperature. The central propulsion shaft rotated at a constant speed of 100 rpm.

When no ice was generated, the system heat flow was calculated using the following equation (Equation 3):
Heat flux = Q (・) = C _{pm (・)} (T _out -T _in )
Here, C _p is the specific heat, and m (•) is the mass flow rate at [kg / sec]. The coolant temperature (T _in and T _out ) and product temperature (T _in and T _out ) were measured with a K-type thermocouple and recorded with a Sper Scientific 4 Channel Datalogging thermometer. If the event included ice formation, the heat flux was determined using the following equation (Equation 4):
Heat flux _{ice consideration} = Q (·) = (C pm (·) (T out - T in)) (100 -% ice) + m (·) λ% ice
Where λ is the latent heat of the phase change from ice to liquid.

  Ice slurry production: An ice slurry was produced using the above-described surface scraping heat exchanger. The coolant was 70% potassium formate and the product was 10% NaCl.

  FIG. 17A shows the heat flow data obtained using Equation 3 and Equation 4 for both the coolant and the product. FIG. 17B shows the temperature profile as a function of time. The temperature plot (FIG. 17B) shows that the product was supercooled to a temperature below the freezing point. The degree of supercooling, in part, determines the concentration of ice that results from spontaneous formation. Spontaneous generation of ice particles occurs (shown by the vertical lines in FIGS. 17A-B) and the temperature of the outgoing product (product out) rises, releasing heat of fusion to make ice. Indicates that FIG. 17A illustrates this by increasing the heat flow of the resulting product with the concentration of ice produced. The temperature of the exiting product remained at the freezing point of the product and ice particles were scraped from the heat exchanger wall after the spontaneous generation event.

Failure mode check:
The device had a monitoring device that could confirm the failure mode by processing and analysis. Physical devices have performance criteria set by calculation and experimental calibration, and deviations from the criteria are used to alert the user to change the operation of the device. Non-characteristic changes in heat flow encourage systematic evaluation of temperature, rotational speed, and torque (individually and in combination) to determine the cause of system failure.

  FIG. 18 shows a representative data set from a scraped surface heat exchanger for a failure that occurs in the form of a coolant line freeze. The coolant was 46% potassium formate and the product was 1% NaCl.

  Section 1 of FIG. 18A shows the large change in system heat flow for both the coolant and product. Along with this change, there was a dramatic increase in the temperature of the outgoing product as well as the temperature of the incoming coolant (coolant in), but the coolant soot temperature was constant. (This indicates that the soot was not exchanging heat with the coolant) (FIG. 18B). Next, the increase in coolant soot temperature seen in Section 2 correlated with the decrease in coolant temperature, indicating the release of frozen plugs from the coolant line.

  19A-C show a representative data set of faults in the form of defects in the method of removing ice from the heat exchanger surface. The coolant was 46% potassium formate and the product was 1% NaCl.

  FIG. 19A shows the change in heat flow for a system similar to FIGS. 18A-B. However, it did not correlate with a large change in the temperature of the incoming coolant, and the temperature of the coolant tank continued to change (indicating that heat was exchanged with the coolant). A rise in the temperature of the product exiting with the change in heat flow (FIG. 19B) and a decrease in the temperature of the exiting coolant were observed. FIG. 19C represents what happens to the scraper rotational speed when the heat flow shown in FIG. 19A is reduced. The correlation in time indicates that the change in heat flow is the result of a change in the scraper rotational speed.

Salt water supercooling

General device description:
A counter-flow surface scraping heat exchanger similar to the embodiment shown in FIG. 6 was constructed and used to produce an ice slurry. This apparatus had a heat exchange surface area of 0.011 m ² , an annular gap of 4.94 mm, and 8 scraper blades. The product flows from the counter-flow heat exchanger into an insulated 1/4 inch (0.64 cm) tube. The product exits the tube and falls into a collection beaker.

  The primary coolant was 70% or 46% potassium formate. The primary coolant was cooled in a separate heat exchanger loop comprised of a copper coil immersed in a dry ice / propanol mixture. The dry ice / propanol mixture creates a uniform -70 ° C soot, through which potassium formate passes. Potassium formate entered the countercurrent heat exchanger at a temperature below the freezing point of the product. In this case, the product is 4.7% NaCl (4.7% brine) by weight.

  All exposed tubes were insulated. The ranges of mass flow rates of coolant and product were (respectively) as follows: 0.011-0.002 [kg / sec] and 0.006-0.001 [kg / sec]. In general, the product entered the countercurrent heat exchanger at a temperature below room temperature but well above the freezing point. The central propulsion shaft rotated at a constant speed of 100 rpm.

  When no ice was generated, the system heat flow was calculated using Equation 3 in Example 4 above. Coolant and product temperatures were measured by a K-type thermocouple and recorded with a Sper Scientific 4 Channnel Datalogging thermometer.

If the event included ice formation, ice mass concentration was found by measuring the increase in brine density. While ice was being produced, the system was evacuated and the 40 micron filter separated salt water and ice particles. The brine separated from the slurry was collected in a flask and the density of this solution was found by fitting a volume plot against the mass of the measured data points. The density of salt water uniquely corresponds to the mass ratio of salt dissolved in water, that is, the concentration of salt water. The concentration of slurry brine was identified using published literature showing the relationship between density and concentration. Since pure water ice had to be drawn from the original salt water, the change in the salt water concentration is an index indicating the mass ratio of ice in the slurry, as shown in the following equation (Equation 5).
Mass ratio _ice =% _ice = 1-(C ₀ / C _s )
Here, C ₀ is the original salt water concentration, and C _s is the salt water concentration in the slurry. An expression of the heat flow rate of the slurry was obtained using the following equation (Equation 6).
Heat flux _{ice consideration} = Q (·) = (C pm (·) (T out - T in)) (1 -% ice) + (m (·) λ ice + C p, icem (·) T out)% _ice
Here, λ _ice is the latent heat of phase change from solid to liquid.

Ice generation using seeds

  The area identified in FIG. 21 shows the use of seed ice to initiate heterogeneous nucleation. Cubic seed ice maintained at a temperature below the freezing point of the solution is generated from a two-phase coolant device as described in Example 5 and shown in FIG. Was put into the flow.

  Thus, ice crystals begin to form on the seed ice in the area highlighted in FIG. Once the crystals begin to form, the seed ice is removed. When crystals are present in the solution, there are now a large number of nucleation nuclei and heterogeneous nucleation begins in the collection beaker. In the identified area of FIG. 21, the temperature of the outgoing brine is below the freezing point and is therefore supercooled, and the heat flow plot (FIG. 21A) shows an increase in heat flow when ice is present in the product. It shows that FIG. 21B shows the temperature profile.

  In FIG. 21, two periods are identified as areas where nucleation has been initiated by cubic seed ice. This is because the product collection beaker was replaced. When a new beaker with no ice crystals is placed under the falling product, initially there are no nucleation nuclei and therefore no ice is formed. Cubic seed ice, maintained again below the freezing point of the solution, was placed in the passage of the supercooled solution falling into the collection beaker and was removed as soon as free floating ice crystals became visible in the collection beaker ( Cubic seed ice was introduced for about 5 seconds).

Ice formation from physical surfaces

  While heterogeneous nucleation occurred in the collection beaker, a physical object was placed in the area at the end of the apparatus flow tube. In this embodiment, it was the tip of a thermocouple probe. FIG. 21 identifies the time zone where heterogeneous nucleation began from the insertion of the object. In the identified area, the temperature of the outgoing brine is below the freezing point and is therefore supercooled, and the heat flow plot (FIG. 21A) shows that an increase in heat flow is obtained when ice is present in the product. ing. About 30 seconds after ice nucleation began, the object was removed from the flow path. Ice nucleation continued because the nucleation nuclei were in the form of ice crystals already present in the flow path.

  The period during which the vacuum system was turned on and the slurry solution was collected is also identified in FIG. An increase in brine concentration was measured. According to Equation 5 from Example 5, the ice mass ratio was calculated to be 0.30.

  The invention is not limited to the embodiments described and illustrated above, but can be varied and modified within the scope of the appended claims.

Claims (41)

A method for producing a flowable ice slurry comprising:
A process of supercooling the liquid,
The process of moving the supercooled liquid through the passage with a stable flow, and disturbing the stable flow of the supercooled liquid, thereby inducing the nucleation of ice in the supercooled liquid and allowing it to flow Producing a fresh ice slurry.   The method of claim 1, wherein the moving step comprises moving the supercooled liquid through a tube or pipe in a stable flow.   The method of claim 1, wherein the supercooling step comprises supercooling brine.   The method of claim 1, wherein the perturbing step comprises producing a flowable ice slurry comprising about 0% to about 60% ice.   The method of claim 1, wherein the disturbing step includes varying a pressure of the supercooled liquid in the passage.   6. The method of claim 5, wherein the perturbing step further comprises introducing an impinging jet with a second supercooled liquid into a stable stream of supercooled liquid.   The perturbing step is performed in a substantially closed system in which the second supercooled liquid is mixed with the previously supercooled liquid, or the second supercooled liquid was first supercooled. 7. The method of claim 6, wherein the method is performed in an open system that at least partially impinges on a substantially static surface of a liquid.   The method of claim 1, wherein the step of disturbing comprises perturbing a stable flow with ultrasound.   The method of claim 1, wherein the disturbing step includes generating a vortex or a vortex in a stable flow.   The method of claim 1, wherein the disturbing step includes creating at least one stagnation point in a stable flow.   The method of claim 10, wherein the disturbing step comprises contacting a stable stream with at least one ice crystal.   The method of claim 10, wherein the disturbing step comprises contacting a stable stream with at least one trip.   13. The method of claim 12, wherein the perturbing step comprises contacting a stable flow with at least one trip located near the center of the supercooled liquid flow.   13. The method of claim 12, wherein the perturbing step comprises contacting a stable flow with at least one trip located near the periphery of the supercooled liquid flow.   The method of claim 12, wherein the trip generates a vortex or spiral.   The trips include post design trips, cross-wire trips, tooth design trips, central tooth design trips, Select from the group consisting of sticky sphere trip, pyramid trip, surface roughness trip, trip with tooth profile combination, dimple tube trip, and bladed cone trip, or combinations thereof 11. The method of claim 10, wherein:   The method of claim 1, further comprising removing heat from the ice slurry.   The method of claim 17, wherein the heat removing step comprises contacting the ice slurry with a heat exchanger.   The method of claim 1, further comprising reducing the free energy of the stable flow using the interface. The process of supercooling
Supercooling highly concentrated liquids,
Supercooling water or less concentrated liquid and mixing supercooled high concentration liquid with supercooled water or less concentrated liquid to form supercooled liquid ;
The method of claim 1 comprising:   The method of claim 1, wherein the moving step includes moving the supercooled liquid through a passageway in a laminar flow.   The method of claim 1, wherein the moving step includes moving the supercooled liquid through the passage in turbulent flow. A method for producing a flowable ice slurry comprising:
A process of supercooling a high concentration liquid,
Supercooling water or a less concentrated liquid, and mixing a supercooled high concentration liquid with supercooled water or a less concentrated liquid to form a supercooled solution;
Moving the supercooled solution through a passage in a stable flow; and disturbing the stable flow of the supercooled solution, thereby inducing ice nucleation in the supercooled solution. Producing a flowable ice slurry.   24. The method of claim 23, wherein the high concentration liquid is brine. A system for producing ice slurry,
A heat exchanger configured to supercool the liquid solution,
A passage coupled to receive a stable flow of the supercooled liquid solution from the heat exchanger, and disturbing the stable flow in the passage to induce ice nucleation in the supercooled liquid solution And a means coupled to the passage for producing a flowable ice slurry.   26. The system of claim 25, wherein the disturbing means includes a jet configured to introduce a supercooled liquid that impinges on the supercooled liquid solution.   26. The system of claim 25, wherein the disturbing means includes an ultrasonic transducer.   26. The system of claim 25, wherein the disturbing means includes at least one stagnation point.   30. The system of claim 28, wherein the stagnation point is a trip.   30. The system of claim 29, wherein the trip is located near a center of the flow of the supercooled liquid solution.   The trips include post design trips, cross-wire trips, tooth design trips, central tooth design trips, Select from the group consisting of sticky sphere trip, pyramid trip, surface roughness trip, trip with tooth profile combination, dimple tube trip, and bladed cone trip, or combinations thereof 30. The system of claim 29, wherein:   26. The system of claim 25, wherein the disturbing means includes at least one vortex or vortex shedding point.   26. The system of claim 25, wherein the passageway includes at least one interface that reduces free energy of the supercooled liquid solution.   26. The system of claim 25, further comprising an inlet positioned to introduce supercooled water that mixes with the liquid solution.   26. The system of claim 25, further comprising a second heat exchanger coupled to receive ice slurry from the disturbing means and configured to remove heat from the ice slurry. An apparatus for inducing ice nucleation in a supercooled liquid,
A conduit configured to be coupled to a subcooled liquid source, and at least one stagnation point coupled to the conduit and positioned to disturb a stable flow of subcooled liquid;
Forming a passage positioned to receive a stable flow of subcooled liquid, and the at least one stagnation point is configured to induce ice nucleation in the subcooled liquid, thereby allowing flow Equipment that produces possible ice slurry.   40. The apparatus of claim 36, wherein the at least one stagnation point comprises a trip.   38. The apparatus of claim 37, wherein the trip is located near the center of the passage.   The trips include post design trips, cross-wire trips, tooth design trips, central tooth design trips, Select from the group consisting of sticky sphere trip, pyramid trip, surface roughness trip, trip with tooth profile combination, dimple tube trip, and bladed cone trip, or combinations thereof 38. The apparatus of claim 37, wherein:   The method of claim 1, wherein the disturbance comprises seed ice pieces that are substantially stable heterogeneous nucleation sites.   The method of claim 6, wherein the second supercooled liquid is different from the previously supercooled liquid.

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