MXPA98003466A - Refrigerator adsorbente equilibr - Google Patents

Abstract

A heat transfer apparatus (2) that uses an absorbent material to generate a cooling effect. The heat transfer apparatus (2) includes a first container (4) containing absorbent material (10) and a second container (6) interconnected to the first (4). A working substance is inside the two interconnected containers (4, 6), The absorbent material (10) and working substance (26, 28) are formed so that the substance is completely absorbed in both liquid and solid state (26, 28) by the absorbent material (10) from the second container (6) in the first (4), cooling the second container (6) and heating the first (4). The complete adsorption includes adsorption of the working substance by vaporization when the working substance is in a liquid phase (26) and adsorption by sublimation when the work substance is in a solid phase (28). The second container (6) contains a compressible foam that accommodates the expansion of the working substance when it changes from liquid to solid phase and prevents the second container from breaking (

Description

BALANCED ADSORBIENT REFRIGERATOR - CROSS REFERENCE TO PREVIOUS REQUEST This application claims priority of the Provisional Patent Application of E. U.A. No. 60 / 010,335, filed on November 1, 1995.

TECHNICAL FIELD The present invention is generally directed to a heat transfer apparatus that uses an adsorbent material to generate a cooling effect.

BACKGROUND OF THE INVENTION Adsorption has previously been used to generate a cooling effect. Adsorption is a process that uses the natural affinity that certain adsorbent materials have for adsorbates. A typical refrigeration cycle employing adsorption includes two phases. During one phase, the dry or changed adsorbent material is exposed to a liquid adsorbate. The affinity that the adsorbent has for the adsorbate causes the adsorbate to enter a state of vapor since it is attracted to the adsorbent. The conversion of the adsorbate from a liquid state to a vapor state is an endothermic reaction that extracts heat from the environment surrounding the liquid, and therefore cools the environment and heats the adsorbent. During the second phase, additional heat is supplied to the adsorbent to expel or desorb the adsorbed vapor, thus recharging the adsorbent. The desorbed steam condenses and cools, and the two-phase cycle is repeated. Zeolite (also called a molecular sieve), is a general term for crystalline metal-aluminosilicate adsorbents that are similar to sand in chemical composition. More 40 natural and 100 synthetic zeolites are known today. The zeolite has a large internal surface area of up to 100 m2 / g, and a glass surface with strong electrostatic fields. The zeolite retains adsorbents by strong physical forces rather than by chemisorption. This means that when the adsorbed molecule is desorbed by the application of heat or by displacement with another material, it leaves the crystal in the same chemical state as when it entered. The very strong adsorption forces in zeolite are mainly due to the cations that are exposed on the glass surface. These cations act as strong localized positive charge sites that attract electrostatically the negative end of polar molecules. As the dipole moment of the molecule is larger, it will be attracted and adsorbed more strongly. Polar molecules are usually those that contain atoms of O, S, Cl or N and are asymmetric. Water is such a molecule. Under the influence of the strong positive charge, localized in the cations, the molecules can have induced dipoles in them. The polarized molecules are then strongly adsorbed due to the electrostatic attraction of the cations. As the molecule is more unsaturated, it can polarize more and adsorb more strongly. The desorption of zeolite powders shows no hysteresis. The adsorption and desorption are completely reversible. However, the zeolite material Pellado, some additional adsorption pressures can occur near the saturation vapor pressure through condensation of liquid in hollow external pellet to the zeolite crystals. Hysteresis can occur when desorbing this macro-port adsorbate. In a typical installation, an adsorbent vessel and a condensation vessel are interconnected. The adsorbent vessel contains an adsorbent such as zeolite and the condensation vessel contains a working fluid, such as the water brine mixture described in the U.S.A. patent. No. 4, 584,852. The condensation vessel may also contain pure water that is completely frozen and then removed from the container, as described in US-A-4,752,310. Assuming the adsorbent is in an unloaded state, the adsorbent vessel is heated to vaporize any working fluid contained therein and drive fluid to the adsorber vessel condensation vessel where it condenses. Both vessels are cooled afterwards. As the adsorbent vessel cools, begins to adsorb steam from the working fluid in the condensation vessel. As the working fluid enters the vapor state, it adsorbs the heat of vaporization from its surroundings, which cools the condensation vessel and the working fluid that remains in the condensation vessel. When the adsorbent is saturated with working fluid vapor, the cycle is complete. The adsorbent vessel is then reheated, causing the steam to return to the condenser and condense, repeating the previous cycle. A disadvantage of the devices described above is that the working fluid, which is typically water, requires the addition of salt to form a brine mixture. Without the brine, the water will freeze and expand completely, breaking the condensation vessel and associated equipment. For example, the condensation vessel ideally includes thin tubes heat exchangers to maximize the rate of cooling in the condensation vessel. Such tubes are particularly prone to fail when subjected to frozen water. In addition, the remaining brine in the condensation vessel tends to harden when the working fluid is adsorbed, reducing the heat transfer efficiency of the condensation vessel. Containers containing a solid refrigerant gel and a compressible insulating material have been used independently of an adsorption system to provide a beverage refrigerant arrangement, as described by US-A-4,357,809. Another disadvantage of existing adsorbent refrigerators is that the capacity of the adsorbent is not equal to the volume of work substance. If the adsorbent capacity is very low, the adsorbent becomes saturated while the substance still works in either a fluid or a solid state. This is ineffective since the adsorbent must be recharged more often than it would be if it were formed to completely adsorb all the working fluid. If the adsorbent capacity is very high, the adsorbent vessel is larger than necessary and therefore ineffective for heating. Accordingly, there is a need in the field for an adsorption apparatus that equals the amount of the work substance to the capacity of the adsorbent and which can continue to adsorb the work substance whether the work substance is in a fluid state or in a solid state without causing damage to the apparatus. The present invention meets these needs and provides additional related advantages.

BRIEF DESCRIPTION OF THE INVENTION In brief, this invention is directed to a heat transfer apparatus that uses an adsorbent material to generate a cooling effect. The invention provides an improvement over the prior art as it is capable of adsorbing a working substance from the solid phase as well as the liquid phase, thus eliminating the need for brine and other additives that reduce the freezing point of the substance of the invention. job. The invention provides another improvement over the prior art since the amount of adsorbent material is balanced to substantially adsorb the entire working substance, thus maximizing the cooling effect of the working substance contained within the heat transfer apparatus. In one embodiment of the present invention, the apparatus includes a first container containing adsorbent material and a second container connected to the first with a conduit. The conduit provides a passage of fluid between the containers and the containers together with the conduit form a sealed volume capable of maintaining a pressure below the atmospheric pressure. The sealed volume contains an amount of working substance that is selected to be substantially completely adsorbed by the adsorbent material. Since the working substance is adsorbed, the second container is cooled. Once the working substance has been completely adsorbed, the first container is heated to desorb the working substance back to the second container. In another aspect of the invention, a portion of the working substance located in the second container is in the solid state. The working substance in the solid state is completely adsorbed by sublimation in the adsorbent material contained in the first container.

In another embodiment of the invention, the second container is housed within an insulated cooling chamber. During adsorption, the second container cools the refrigerated chamber appropriately to store food or other substances that require refrigeration. In yet another embodiment of the present invention, a second container is adapted for use with working substances that expand during freezing. The second container contains a compressible material which is compressed as the working substance changes from a liquid state to a solid state. The amount of compressible material contained within the second container and the amount of working substance contained therein are selected so that when the working substance is frozen, the force exerted by the working substance and the material. compressible compressed in the second container is less than the pressure limit of the second container. In still another embodiment of the invention, the first container is used to heat the hot tank of a Stirling engine and the second container is used to cool the cold tank of the engine. The first and second containers thus increase the differential temperature of the tanks between which the Stirling engine operates and increase the efficiency of the engine. In another embodiment of the invention, the conduit between the first and second containers contains a turbine. The turbine is coupled to an energy transmission device outside the conduit so that when steam passes from the second conduit to the first conduit by adsorption, the steam rotates a rotor in the turbine, generating energy that is transmitted to the energy transmission device. . In one embodiment of the present invention, the heat transfer apparatus includes a thermal voltaic device having a hot side and a cold side. The apparatus is positioned to increase the temperature of the hot side with the adsorbent vessel and reduce the temperature of the cold side with the condensation vessel, thus increasing the output voltage of the thermal device. The present invention also provides a method for transferring heat and a working substance between a first container containing an adsorbent material and a second container connected to the first container with a conduit. The method comprises allowing a liquid portion of the working substance to vaporize by adsorption and transferring the second container to the first container, thus causing a remaining portion of the liquid working substance in the second freezer container, and continues to adsorb the frozen portion of the working substance by sublimation until the working substance has been completely adsorbed. These and other aspects of this invention will be apparent with reference to the following detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side view partially cut away of an embodiment of the present invention with an adsorbent vessel to a condensation vessel. Figure 2 is a cross-sectional view of an embodiment of the invention wherein the condensation vessel includes heat exchanger tube and is housed in a refrigerated box. Figure 3 is a detailed side view of the heat exchanger tube of Figure 2 including a compressible material insert and fins. Figure 4 is a cross-sectional view taken substantially on line 4-4 of Figure 3. Figure 5 is a detail of the compressible material insert of Figure 3. Figure 6 is an embodiment of the present invention wherein two adsorbent vessels are connected to a single condensation vessel. Figure 7 is a mode of the present invention wherein two adsorbent vessels are connected to separate heat exchangers to provide continuous cooling of the cooled box. Fig. 8 is a schematic view of an alternate embodiment of the present invention wherein two adsorbent containers are used together with the condensation vessel to drive a turbine. Figure 9 is a schematic of an alternative embodiment of the present invention wherein the adsorbent vessel and the condensation vessel are integrated in a basic Stirling engine cycle. Fig. 10 is an embodiment of the present invention wherein two adsorbent containers are connected to a single condensation vessel and include accumulators for precondensing a working substance, Fig. 11 is an embodiment of the present invention that includes both burned sources with gas as electrical heat. Figure 12 is an embodiment of the invention that includes an internal heat source, retained machined adsorbent material, and an external annular heating or cooling device. Figure 13 is a cross-sectional view of the embodiment of Figure 12 taken substantially on line 13-13. Fig. 14 is an embodiment of the invention that includes a hollow internal heat transfer source and an external annular heat transfer source, both sources of heat transmission being suitable for heating or cooling the adsorbent material. Figure 15 is a cross-sectional view of the embodiment of Figure 14 taken substantially on line 15-15.

DETAILED DESCRIPTION OF THE INVENTION As mentioned before, the present invention is directed to an apparatus for using a heat source to generate a cooling effect. The apparatus includes an adsorbent material that cyclically adsorbs and desorbs a working substance, causing a heat transfer. The present invention increases the efficiency of the adsorption cycle by equalizing the capacity of the adsorbent material to the amount of the work substance. The invention further increases the efficiency of the adsorption cycle by retaining the working substance in a container that does not explode when the working substance solidifies, thus allowing the adsorption to continue after the working substance has solidified. A representative apparatus in accordance with the present invention is shown in the figures for the purpose of illustration. As shown in Figure 1, an adsorbent vessel 4 of an apparatus 2 is connected to a condensation vessel 6 with a tube 8 passing through an opening 9 located in the base of the adsorbent vessel. The adsorbent vessel 4 is filled with an adsorbent material 10 having a strong affinity for polar working substances. The tube 8 extends through the adsorbent vessel 4 and is surrounded by the adsorbent material 10. The tube 8 contains perforations 12 which allow the vapor to pass back and forth between the adsorbent material 10 and the tube. A fabric of 14 mesh covers the perforations 12 and prevents the adsorbent material 10 from entering the tube 8 through the perforations. The adsorbent vessel 4 contains a plug 16 for draining the adsorbent vessel and for accessing the vessel for maintenance purposes. A heat source 18 is located adjacent the adsorbent vessel 4 and is positioned to heat the adsorbent vessel and its contents. The heat source 18 can be cycled between an active position where it generates heat, heating the adsorbent vessel 4 and causing the adsorbent material 10 to release vapors (desorb), and an inactive position wherein the adsorbent vessel 4 and its contents can be cooled. The heat source can take the form of an electric heater, combustion heater, the sun, or heating can be achieved by passing magnets over copper pipe, for example, the container 4. Other known heating methods can also be used in the technique. In one embodiment, the tube 8 contains a vacuum valve 20 and a bellows 22. The vacuum valve 20 can be moved between an open position, as shown in solid lines in Figure 1 where the condensation vessel 6 can communicate. with the adsorbent vessel 4 through the tube 8, and a closed position indicated in invisible lines in figure 1 wherein the condensation vessel is sealed in communication with the adsorbent vessel. The condensation vessel 6 contains a view window 24 which allows to see the condensed liquid working substance 26 and solid working substance 28 contained in the condensation vessel. In another embodiment, the vacuum valve 20 and bellows 22 are replaced with a commercial grade vacuum valve, or other suitable valve device. The adsorbent vessel 4 contains a second opening 30 which is connected to a vacuum valve 32 by a tube 8. The vacuum valve can be connected to a vacuum source 33 for purposes of evacuating the adsorbent vessel 4. It is desired to reduce the pressure in the adsorbent vessel 4 in order to reduce the temperature at which the liquid working substance 26 will be vaporized and adsorbed by the adsorbent material 10. However, depending on the characteristics of the adsorbent material 10 and the work substance, they are also possible pressures a and on atmospheric pressure. The vacuum valve 32 can be positioned between an open position that allows communication between the adsorbent vessel 4 and the vacuum source 33, and a closed position where the adsorbent material 4 is sealed from the vacuum source. Prior to the operation of the apparatus 2, the vacuum valve 32 is opened, providing a fluid connection between the adsorbent vessel 4 and the vacuum source 33. The vacuum valve 30 is then opened, providing a fluid connection between the adsorbent vessel 4. and the condensation container 6. The pre-heat in the adsorbent vessel 4 and the condensation vessel 6 is reduced. The vacuum valve 32 is then closed and the apparatus 2 is ready for operation. In one embodiment, the pressure inside the container 4 is reduced to an absolute pressure of 4mm of mercury (ie 4mm of mercury over the total vacuum), however other pressures are also possible, depending on the type of adsorbent material 10 and substance. of work contained within Laparato, as well as the temperature at which the device is subjected. In operation, the apparatus 2 cycles between an adsorption phase and a desorption phase. In the desorption phase, the heat source 18 is activated and heats the adsorbent vessel 4 and the adsorbent material 10, causing any liquid working substance contained in the adsorbent material 10 to vaporize. The working substance vapor passes from the adsorbent material 10, through a 14 mesh cloth and perforations 12, to the tube 8 and then into the condensation vessel 6 where it condenses, which forms a pool of liquid working substance 26. In one embodiment, where the working substance is water, the adsorbent vessel is heated to a temperature of 121.1 ° C to desorb the steam of working substance. Other temperatures are also possible, depending on the characteristics of the adsorbent material 10, the work substance, and the amount of work substance that is desorbed during the desorption process. As shown in Figure 1, the condensation vessel is preferably placed below the adsorbent vessel 4, allowing gravity to assist the passage of condensate from the adsorbent vessel to the condensation vessel.

Once the working substance vapor has been desorbed from the adsorbent vessel 4 in the condensation vessel 6, the vacuum valve 20 is closed and both the condensation vessel 6 and the adsorbent vessel 4 are allowed to cool. In one, both the adsorbent vessel and the condensation vessel cool to room temperature, approximately 21.1 ° C. The cooling rate of the adsorbent vessel 4 can be accelerated by adding a cooling source 36. However, the cooling source is not required for operation of the apparatus 2. Examples of cooling sources include fans, cooling jackets and other thermal deposits. Although the cooling source shown in Figure 1 is external to the adsorbent vessel 4, it can also be extended into the adsorbent vessel to more efficiently cool the adsorbent material 10 therein. When the adsorbent vessel 4 and the condensation vessel 6 have cooled, the adsorption chiller 2 is ready to begin the adsorption phase. The vacuum valve 20 opens allowing fluid communication between the adsorbent vessel 4 and the condensation vessel 6, and providing a sudden, immediate cooling effect. The adsorbent material 10 adsorbs the liquid working substance 26, causing it to change phase from a liquid to a vapor and pass through the tube 8, the perforations 12, the mesh fabric 14, and into the adsorbent material 10. A As the liquid working substance passes from the liquid state to the vapor state, it extracts the heat of vaporization from the surrounding liquid working substance and from the condensation vessel 6 causing the water and condensing vessel to cool. As the condensation vessel 6 and its contents cool, the liquid working substance begins to form the solid working substance 28. As the adsorption phase continues, the liquid working substance 26 disappears either because it is adsorbed by the adsorbent material 1 0 or because it is completely converted to solid 28. Once the liquid working substance 26 has disappeared from the condensation vessel 6, the adsorption continues as the solid working substance 28 is directly sublimed to a vapor that is adsorbed by the adsorbent material 1 0. When the liquid 26 and solid 28 have been adsorbed substantially completely, the cycle is complete. The heat source is then reactivated by impelling water vapor through the tube 8 back to the condensation vessel 6 to repeat the refrigeration cycle. As used herein, the term substantially completely adsorbed means that substantially all of the working substance, whether liquid phase or solid phase, has been adsorbed to a vapor phase, and transferred from the condensation vessel 6 to the vessel. adsorbent 4. The capacity of the adsorbent material 10 (that is, the maximum amount of the working substance it retains) relative to the amount of work substance in the apparatus 2 is an important feature of the invention. In one embodiment, the adsorbent material 10 is MOLSIV type 13X zeolite manufactured by UOP Inc., of Des Plaines, Illinois, and the working substance is water. In this embodiment, the capacity of the adsorbent material 10 is adjusted to a value such that the adsorbent material completely adsorbs both the liquid water 26 and the ice 28. The volume of the adsorbent material 10 is selected based on the desired cooling load. and speed to be 360.5162 cm3 (that is, 0.19023 kg). The working substance is selected to be 60 cubic centimeters of water, (ie, 28.5% by weight of the adsorbent material 10), and the volume of the condensation vessel 6 is formed to be equal to the volume of the working substance. The amount of water desorbed by the adsorbent material 10 is 20 cubic centimeters when the adsorbent material is heated to 121 .1 ° C. The remaining 40 cubic centimeters of water remain in the adsorbent material 10 after desorption. With this combination, the waste water in the condensation vessel 6 is completely frozen approximately 1 1 seconds after the vacuum valve 20 is opened and the adsorption phase of the cycle begins. With no direct work load applied to the system (ie, no source applying heat to the condensation vessel), the frozen residue is completely adsorbed by the adsorbent material approximately 120-160 minutes later. The adsorbent to work substance ratios and the temperatures selected above were selected to provide the indicated cooling times. Other relationships and temperatures are possible that adsorb and desorb more of the total work substance. These relationships will reduce the frequency-with which the adsorbent material 10 must be desorbed. As discussed above, the adsorbent material 10 is zeolite and the working substance is water in one embodiment. Other working substances and other adsorbent materials are also possible, which have an affinity for the working substances. Said working substances include NH3, H2, S, N2, CO2, etc. , as well as fluorine, chlorine and hydrocarbons, and mixtures thereof. These substances have affinities that vary for adsorbent materials, as discussed below. Other adsorbent materials include molecular sieves, silicon gel, activated alumina and other similar sodalite structures, including powders, pellets, particles, solid forms and gels thereof. The outer surface area of the adsorbent molecular sieve crystal is available for adsorption of molecules of all sizes, while the inner area is available only for molecules small enough to enter the pores. The external area is only about 1% of the total surface area. Materials that are too large to adsorb internally will commonly be adsorbed externally to the degree of 0.2% to 1% by weight. Molecular sieves are available in a wide variety of types and forms. By choosing the appropriate adsorbent and operating conditions, it is possible to adapt the molecular sieves to a number of specific applications. Molecular sieves will not only be based on size and configuration, but will also adsorb preferably on the basis of polarity or degree of unsaturation. In a mixture of molecules small enough to enter the pores, as a molecule is less volatile, it will be more polar and more unsaturated, it will be held more tightly within the crystal. For example, in one embodiment of the present invention, the word fluid is a mixture of CO2 and water. CO2 vaporizes more easily than water. At the beginning of the adsorption phase of the cycle, CO2 vaporizes immediately by providing an immediate cooling effect. Water vaporizes more slowly but over a long period, providing long-term cooling. The CO2 in addition to providing an immediate cooling effect, improves the heat transfer rate of the heat source 18 to the adsorbent material 10, thus reducing the time and energy required to desorb the adsorbent material. Substances such as nitrogen can be used in combination with water. Nitrogen provides thermal conductivity, increasing the efficiency with which heat can be transferred away from the adsorbent material during desorption. Since the adsorbent material 10 does not adsorb nitrogen as strongly as water, nitrogen does not prevent the adsorbent material from adsorbing water. In an alternate embodiment of the device illustrated in FIG. 1, the vacuum valve 20 is eliminated. As a result, the adsorbent material continuously adsorbs the working substance and continuously cools instead of suddenly the condensation vessel and its contents. In the embodiment illustrated in Figure 1, the diameter of the adsorbent vessel 4 is 2.4 times the diameter of the tube 8. However,, other tube diameters and configurations are also possible. For example, the portion of the tube 8 that is placed inside the adsorbent vessel 4 can be divided into a plurality of smaller tubes, each with perforations 12 and mesh fabric 14. The increased number of tubes increases the rate of vapor transfer between the adsorbent 10 and the condensation vessel 6. As illustrated in Figure 1, the heat source 18 is placed external to the adsorbent vessel 4, however, other arrangements are possible. For example, the heat source 18 can be placed inside the adsorbent vessel 18 to thereby more efficiently heat the adsorbent material 10. In such embodiment, the heat source 18 includes a water-resistant alloy element, and the adsorbent material 10 is Adheres directly to the element to provide an intimate bond for efficient heat transfer. In this embodiment, the alloy, or other suitable material, is capable of being exposed to air without melting while under a heat load. The binder material can be its polyphenylene lfide (PPS) or aluminum phosphate. Aluminum phosphate is advantageous as a binder since it adds structural stress by combining activated alumina and / or aluminum oxide with the zeolite and can be heated above 315.5 ° C. PPS does not add much effort but does not require the addition of activated alumina or aluminum oxide, so that 100% of the adsorbent can be zeolite. In a embodiment illustrated in Figures 12 and 13, the adsorbent material is in the form of machined adsorbent discs 50 which are stacked in a solid heater element 52 formed of a material such as alloy, which can be electrically heated by applying a voltage to the cables 53. Each adsorbent disk 52 has holes 54 that allow the desorbed steam to pass between the adsorbent discs 50 and the tube 8. The adsorbent discs 50 can be machined to provide hard surfaces 55 that allow air to pass between the adsorbent discs to cool or heat the adsorbent discs as desired. A heat transfer jacket 56 surrounds annularly the outer surfaces of the adsorbent discs 50. The heat transfer jacket is connected to a heat exchange source 57 to vary the temperature of the adsorbent vessel 4. A fluid 58 such as water passes through. between the heat transfer jacket 56 and the heat exchange source 57 for transferring heat between the adsorbent discs 50 and the heat exchange source 57. The adsorbent discs 50 can be machined to any desired shape and can be stacked in heating elements 52 having varying lengths so as to fit inside the adsorbent vessels 4 having varying dimensions.

As shown in Figure 12, the heat exchange source 57 and heat transfer jacket 56 can act to transfer heat to or from the adsorbent discs 50. When the heat exchange source 57 and the heat transfer jacket 56 act to heat the adsorbent discs 50, increase the speed at which the adsorbent discs desorb the work substance, reducing the time required to desorb the adsorbent vessel 4, thus reducing the overall cycle time. When the heat transfer jacket 56 and heat exchange source 57 act to cool the adsorbent discs 50, they can immediately extinguish the adsorbent discs, reducing the time required to cool the adsorbent discs before the next adsorption phase, once more reducing the overall cycle time.

In another embodiment illustrated in Figures 14 and 15, the adsorbent material 10 is in the form of powder or pellets. A heating element 300 formed of a material such as an alloy passes through the adsorbent material 10 and is connected to the heat exchange source 57. The heating element 300 has an annular cavity 302 through which fluid passes. 58. The heat transfer jacket 56 is also coupled to the heat exchange source 57, and also contains fluid 58. As shown in Figs. 14 and 15, the tube 8 bifurcates into perforated sections 310 and 312. perforated sections 310 and 312 contain perforations 12 to allow vapor to pass between the adsorbent material 10 and the perforated sections, and the mesh fabric 14 to prevent the adsorbent material from entering the perforated sections. Although the two perforated sections 310 and 312 are shown in Figures 14 and 15, a greater number of perforated sections is possible as well as maximizing the vapor transfer rate between the adsorbent material 10 and the perforated sections. As discussed above in relation to the embodiment illustrated in Figures 12 and 13, the heat exchange source 57, heat transfer jacket 56 and annular heating element 300 can act to heat or cool the adsorbent material 10. When fluid hot, such as water or other suitable fluid, passes from the heat exchange source 57 through the heat transfer jacket 56 and through the annular cavity 302 and the heating element is heated with an electric current supplied through of the cables 53, the speed at which the adsorbent material 10 adsorbs is increased, reducing the time required to prepare the adsorbent vessel 4 for adsorption. When cold fluid, such as water or other suitable fluid, passes from the heat exchange source 57 through the heat transfer jacket 56 and through the annular cavity 302, the adsorbent material 10 is extinguished immediately, further reducing the time required to prepare the adsorbent vessel 4 for adsorption after it has been heated and before desorption. In another embodiment illustrated in Figure 2, the condensation vessel is replaced by a heat exchanger 36 that is placed inside an insulated case 38. The operation of the adsorbent vessel 4 is substantially the same as the operation of the adsorbent vessel discussed above. in relation to figure 1. As the heat exchanger cools during the adsorption phase, it cools the box 38. The box 38 can then be used to store items, such as food, that require refrigeration. The heat exchanger 36 contains heat exchanger tube 40 which serves the same purpose as the condensation vessel 6 of Figure 1. However, the heat exchanger tube 6 provides a larger heat transfer surface area than the condensation vessel 6 and therefore more efficiently cools the case 38. The heat exchanger tube 40 is oriented at a downward angle to Take advantage of gravity forces as the heat exchanger tube fills with condensate. The heat exchanger tube 40 is shown in greater detail in Figure 3. In this embodiment, the working substance is a material that expands when solidified, such as water. As seen in Figure 3, the heat exchanger tube 40 contains a foam or other compressible material 42 that accommodates the expansion of the work substance 26 as it freezes. The freezing water exerts pressure on the walls of the heat exchanger tube 40, creating a tangential resistance, and on the compressible material 42. Since the compressible material 42 is more compressible than the walls of the heat exchanger tube, it is deformed thus preventing that the pressure exceeds the tangential resistance of the heat exchanger tube 40 as the working substance freezes completely. Once the substance of the work has been completely frozen, it continues to be sublimated and adsorbed by the adsorbent material 10 as previously discussed. As used herein, the tangential resistance refers to the tension beyond the walls of the heat exchanger tube 40 or another container where the compressible material 42 is burst. It is desired to form and place the compressible material 42 in the heat exchanger tube 40 to leave a flow area in the heat exchanger tube suitable to allow the flow of steam of working substance through the heat exchanger tube during adsorption. At the same time, it is desired to provide sufficient compressible material 42 so that the frozen working substance does not completely compress the compressible material 42 and then burst the heat exchanger tube 40. Therefore, in one, the ratio of the volume of Work to the volume of compressible material 42 is selected so that when the working substance freezes and expands, compressing the compressible material 42, the combined pressure exerted by the frozen working substance, any remaining liquid working substance, and the material compressible 42 is less than the tangential resistance of the heat exchanger tube 40.

In the embodiment illustrated in Figure 3, the heat exchanger tube comprises a single section having openings 46 communicating with the adsorbent vessel 4. Other embodiments are also possible. For example, the heat exchanger tube 40 can be divided into several lengths, each having openings 46 communicating with the adsorbent vessel. Said arrangement increases the exposure of the fluid within the heat exchanger tube to the adsorbent vessel 4. In another embodiment, the heat exchanger tube can be adjusted with fins 48 which increase the heat rate transferred from the box 38 to the heat exchanger tube, as well increasing the speed at which the box cools. In one embodiment of the invention, the compressible material 42 has a triangular cross-sectional shape as shown in Figure 4. This shape allows the working substance 26 to pass through the tube around the compressible material 42. This shape also forces the working substance 40 contained within the heat exchanger tube 40 for the walls of the tube for maximum heat transfer efficiency. Other forms that serve to place the working substance on the walls for maximum heat transfer are also possible. As shown in Figure 5, the slots 44 allow the working substance 26 to pass from one side of the compressible material 42 to the other, thus improving the rate at which the liquid and vapor pass through the tube 40. In In this embodiment, the slots 44 are arranged in a helical pattern as shown in Figure 5 to allow liquid and vapor to pass more easily from one side of the compressible material 42 to another without compromising the structure of the compressible material 42. The helical arrangement of the grooves also serves to maximize the tangential strength in the heat exchanger tube 40 created when the compressible material 42 is compressed. Although the compressible material 42 is shown in Figure 3 placed in the heat exchanger tube 40, the compressible material 42 can be placed in any container that is subjected to flash when the liquid contained therein freezes and expands. For example, the compressible material 42 can be placed in an external water tap to prevent the key from breaking when the ambient temperature drops below freezing. In these embodiments, the compressible material 42 can have any shape that conforms to the shape of the container in which it is placed, and does not need to be triangular or elongated, as shown in Figures 3 and 4. The compressible material can be placed inside the container so that it is adjacent to a first wall of the container and separated from a second wall of the container. In this way, the compressible material acts to isolate the first wall of the container, and to place the working substance adjacent to the second wall of the container for maximum heat transfer between the working substance and the second surface.

The pellets of compressible material can be used in containers in which the shape of the container does not easily accommodate a single piece of compressible material. Although the heat exchanger tube 40 is typically made of a rigid, thin-walled, thermally conductive material, the compressible material 42 can also be installed in a container having flexible walls. In this embodiment, both the walls of the container and the compressible material 42 are bent when the liquid contained therein freezes. Other applications of the compressible material 42 will be known to those skilled in the art. In another embodiment of the present invention, illustrated in Figure 6, two adsorbent vessels 4 are connected to the condensation vessel 5. Each adsorbent vessel 4 is operated substantially in the same manner as previously discussed, but the two adsorbent vessels are operated outside of phase so that when an adsorbent vessel is being heated by a heat source 18 and desorbs steam and condenses in the condensation vessel 6. Although the heated vessel desorbs steam, the vacuum valve 20 connected directly to the container is closed to prevent the condensate from adsorbing immediately by the adjacent adsorbent vessel. The valve 21 is opened to allow the condensate to condense in an accumulator 23 without interrupting the simultaneous adsorption conducted by the other adsorbent vessel 4. When the desorption of the desorption vessel is complete, the valve 20 associated with the desorption vessel is opens, allowing the working substance to flow from the accumulator 23 in the condensation vessel 6. In one, the heat sources 18 and adsorbent vessels 4 are formed so that when an adsorbent vessel is completely desorbed, cool, and be ready to adsorb, the other adsorbent vessel becomes saturated and ready to desorb. The papers of the recipients are then reversed; the containers desorbed previously adsorbed from the condensation vessel 6 and the adsorbing vessel previously desorbed in the accumulator 23. Although two adsorbent vessels are shown in Figure 6, other configurations using more adsorbent vessels are also possible. Said modalities are advantageous since they eliminate the need to exactly match the desorption time for one vessel at the time of adsorption for the other. Figure 7 illustrates a continuous cycle using multiple adsorbent systems together. Each adsorbent vessel 4 is coupled to a separate heat exchanger 36 that contains heat exchanger tube 40. As to the embodiment illustrated in Figure 6, the adsorbent vessels 4 are operated out of phase, so that when an adsorbent vessel 4 adsorbs the working substance from the heat exchanger 36 to which it is connected, the other adsorbent vessel desorbs the working substance to its heat exchanger. In this way, the insulated case 38 can be maintained at a substantially constant temperature.

The box 38 has an upper freezer portion and a lower freezer portion. The upper cooling portion contains a relatively high heat exchange tube density per unit volume of the box to achieve the low temperatures typically required to freeze food. The lower cooling portion contains a lower density of heat exchanger tube per unit volume of the box than the freezing portion, and is suitable for maintaining food at typical refrigerator temperatures above 0 ° C. Other embodiments that employ more than two adsorbent containers and heat exchangers are also possible. Said modalities are advantageous since they eliminate the need to exactly match the desorption time for one vessel at the time of adsorption of the other. Figure 8 illustrates an embodiment of the present invention wherein two adsorbent vessels 40 and 62 are connected to a condensation vessel 66. The flow of adsorbent vapor between the adsorbent vessels 60 and 62 and the condensation vessel 66 drives a turbine 68 located to the inlet 70 of the condensation vessel for supplying power to the power transfer equipment 72. The valves 74 and 76 can be opened or closed as desired to allow communication of the adsorbent vessels 60 and 62 with each other to the vessel. condensation 66. The bypass valves 75, 76, 77 and 78 allow condensate to return to the condensation vessel 66 through the accumulators 79 and 71. In operation, the adsorbent vessel 60 is in a fully saturated state and the adsorbent vessel is 62 is in a completely desorbed and loaded state. In a typical installation, the flow rate of working substance during desorption is too low to generate power in turbine 68. Therefore, when the first adsorbent vessel 60 is heated, the vapor leaving the vessel is sent through of the diverter tube 64 around the turbine 68 and in the accumulator 79. The second adsorbent vessel 62 adsorbs vapor from the condensation vessel 66, causing steam to pass through the turbine 68. As the vapor passes through the from turbine 68, the turbine rotates. The rotational movement of the turbine is transferred by energy transfer equipment 72 using means known in the art, such as a highly sealed arrow or a swirl current coupling. Once the second adsorbent vessel 62 is saturated with steam and the first adsorbent vessel 60 is fully charged, the papers of the containers are inverted. Valves 75, 76 and 77 are closed, and valves 74 and 78 are opened. The first adsorbent vessel 60 adsorbs vapor from the condensation vessel 66, driving the turbine 68, while the second adsorbent vessel 62 desorbs steam through the divert tube 65 in the accumulator 71.

Other applications of the adsorbent cooling device described in the present invention are also possible. For example, the apparatus can be used to reduce the cold side temperature of a Stirling engine, thus increasing the efficiency of the engine. Figure 9 illustrates a basic regenerative Stirling engine cycle, as described in the U.A.A patent. No. 5,456,076 which is incorporated herein by reference. The basic Stirling engine cycle to a minimum comprises: a heat source 81 that supplies heat energy to a hot region 82, a heat sink 84 that removes heat from a cold region 83, a thermally conductive gaseous working fluid 85 that carries heat energy between the hot cylinder region 86 and the cold cylinder region 87, a displacing piston 88 alternating in a displacer cylinder 89 having a hot chamber 90 and a cold chamber 91, the hot and cold chambers being connected by a Heat-insulated regenerative heat exchanger 92, an energy piston 93 alternating in an energy cylinder 94, a means for converting the movement of the energy piston into useful energy such as a rotating crankshaft, and a means for controlling the movement time of the displacer relative to the piston of the piston. Energy. The energy piston 93 and displacement piston 88 can float freely, as in a linear floating Stirling generator, or mechanically connected. In this embodiment, the heat source 81 includes an adsorbent vessel, and the heat sink 84 includes a condensation vessel of the type previously described. The adsorbent vessel and condensation vessel heat and cool the heat source 82 and heat sink 83, respectively, increasing the efficiency of the engine. In addition, the regenerative heat exchanger 82 can be replaced with a combination of adsorbent vessel / condensation vessel of the type previously described. The heat source 81 can include solar energy, so that during the day, the heat source heats adsorbent material, charging the adsorbent vessel. At night the adsorbent vessel adsorbs the working substance of the condensation vessel, heat the adsorbent vessel and cool the condensation vessel. In this way, the introduction of the adsorbent vessel and the condensation vessel serves to store solar energy and keep the Stirling engine operating, even at night. In another alternate embodiment of the invention, the adsorbent cooler can be used to improve the efficiency of thermal voltaic cells. The adsorbent cooler is used to reduce the cold side temperature of the voltaic cells and therefore increase the voltage output. Other modalities are also possible. For example, the heat transfer apparatus can be used to cool a flat plate used for fish processing, or to cool integrated computer circuits, power substations or vehicles. In each embodiment, the relatively low grade heat that is available is used to generate the desired cooling effect.

Figure 10 illustrates an embodiment of the invention wherein the first and second adsorbent vessels 4 and 104 operate with a single condensation vessel 6 for cooling a computer integrated circuit 180. Although the first adsorbent vessel 4 is desorbed to an accumulator 23 with the open valve 21 and the bypass valve 27 and vacuum valve 20 is closed, the second adsorbent vessel 104 adsorbed from the condensation vessel 6 with the vacuum valve 120 and valve 121 closed and the bypass valve 127 open. When the second adsorbent vessel 104 has completed adsorption and the first adsorbent vessel 4 has completed desorption, the valve positions are reversed and the adsorbent vessel 4 begins to adsorb as the adsorbent vessel 104 desorbs in the accumulator 123. this way, the computer integrated circuit 180 is continuously cooled. Figure 1 1 illustrates an alternate embodiment of the present invention wherein the adsorbent vessel can be heated by a gas burner assembly 201 which evacuates through the gas port 202 or an electric heating element 203 or by gas or hot liquid which flows through the inlet port 212 and out through the outlet port 214. The method for heating the adsorbent material 10 contained in the adsorbent vessel 4 may be chosen based on the availability of the heat source at the time of desorption . The inlet port 212 and outlet port 214 can be connected to any convenient heat source, such as a vehicle radiator. A heat exchanger 210 is also provided to reduce the temperature of the adsorbent vessel 4 once it has been desorbed. Any inlet port 205 is supplied to allow maintenance of the adsorbent vessel 4 and its controls 207. The vacuum port 32 can be connected to a vacuum source (not shown) for evacuation of the adsorbent vessel at pressures less than atmospheric pressure. From the foregoing it will be appreciated that, although specific embodiments of the invention have been described for purposes of illustration, various modifications may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not limited except by the appended claims.

Claims (57)

1. CLAIMS 1 .- A heat transfer apparatus (2) that uses a heat source to generate a cooling effect, the apparatus comprising: a first container (4) having a first opening (9) and containing an adsorbent material ( 10) that has an adsorbent capacity; a second container having a second opening, the second opening connected to the first opening (9) of the first container (4) with a conduit (8), the conduit providing a passage of fluid between the containers, the containers and the conduit which forms a sealed volume capable of maintaining less than the atmospheric pressure in them; and an amount of working substance (26, 28) within the sealed volume, the amount including first and second portions of working substance in the second container (6), the working substance being capable of being adsorbed by the adsorbent material (10), the adsorbent capacity of the adsorbent material being sufficient to adsorb the first portion of the work substance, freeze the second portion of the work substance, and adsorb, by sublimation p "ßr at least a substantial part of the second portion of the working substance from the second container when the entire second portion of working substance in the second container is in a solid state.
2. 2. - The heat transfer apparatus according to claim 1, further comprising a valve positioned in the conduit and movable between an open position with the working substance free to move between the first and second containers and closed position with the working substance restricted from moving between the containers.
3. 3. The heat transfer apparatus according to claim 2, wherein the valve is in the closed position and substantially all of the working substance is retained by the adsorbent material.
4. 4. The heat transfer apparatus according to claim 1, wherein the second container has a third opening therein, further comprising a third container connected to the third opening, the third container having an adsorbing material and an adsorbent capacity, wherein the third container is capable of being heated by a heat source while the first container adsorbs the work substance, and the first container is capable of being heated by the heat source while the third container adsorbs the work substance.
5. 5. The heat transfer apparatus according to claim 1, wherein the second container is a cooling element for cooling a volume surrounding the second container.
6. 6. The heat transfer apparatus according to claim 1, wherein the amount of work substance (26, 28) is not greater than the adsorbent capacity of the adsorbent material at a temperature and pressure selected from the sealed volume so that the working substance is capable of being substantially completely adsorbed by the adsorbent material (10).
7. 7. The heat transfer apparatus according to claim 1, wherein the sealed unit has an internal absolute pressure of 4 mm of mercury.
8. 8. The heat transfer apparatus according to claim 1, wherein the adsorbent material has a weight and the working substance has a weight that is 28.5% by weight of the adsorbent material.
9. 9. The heat transfer apparatus according to claim 1, further comprising a heat source placed close to the adsorbent material to heat the adsorbent material and evaporate the working substance therefrom, the source of heat being controllable between an active state where the heat source heats the adsorbent material and an inactive state.
10. 10. - The heat transfer apparatus according to claim 9, wherein the heat source is placed external to the first container.
11. The heat transfer apparatus according to claim 9, wherein the heat source is placed inside the first container.
12. 12. - The heat transfer apparatus according to claim 11, wherein the heat source is thermally coupled to the adsorbent material.
13. 13. The heat transfer apparatus according to claim 1, wherein the heat source is attached to the adsorbent material.
14. 14. The heat transfer apparatus according to claim 9, wherein the first container is capable of achieving a temperature of approximately 21.1 ° C when the heat source is in its inactive state.
15. 15. The heat transfer apparatus according to claim 9, wherein the heat source is heated by solar energy.
16. 16. The heat transfer apparatus according to claim 1, wherein the adsorbent material is a zeolite.
17. 17. The heat transfer apparatus according to claim 1, wherein the working substance is water.
18. 18. The heat transfer apparatus according to claim 1, wherein the working substance is a first adsorbate, further comprising a second adsorbate, the first adsorbate being adsorbed by the adsorbent at a slower rate than a speed to which the second adsorbate is adsorbed by the adsorbent.
19. 19. - The heat transfer apparatus according to claim 18, wherein the first adsorbate is water and the second adsorbate is carbon dioxide.
20. 20. The heat transfer apparatus according to claim 1, wherein the adsorbent is a first adsorbent and the working substance is a first adsorbate, further comprising a second adsorbent and a second adsorbate, the first adsorbate being adsorbed by the first adsorbent at a different speed than a rate at which the second adsorbate is adsorbed by the second adsorbent.
21. 21. The heat transfer apparatus according to claim 1, wherein the second container has a flash pressure limit, which further comprises compressible material placed inside the second container, the compressible material can be compressed by the substance of the invention. work as it changes from a liquid state to a solid state between an uncompressed volume and a smaller compressed volume, the compressible material and working substance that exerts a selected pressure in the container that is less than the flash pressure limit .
22. 22. The heat transfer apparatus according to claim 1, wherein the first container has a vacuum opening therethrough and an internal pressure, further comprising a vacuum valve connected to the vacuum opening, the Vacuum valve can be connected to a vacuum source and can be moved between an open position with the vacuum source in fluid communication with the first container to reduce the internal pressure of the first container and a closed position with the first sealed container of the vacuum source.
23. 23. The heat transfer apparatus according to claim 1, further comprising a Stirling engine having an engine efficiency and operating between a hot tank and a cold tank where the second tank is placed to cool the tank cold, reducing a temperature at which the cold tank removes heat from the Stirling engine, and the first container is placed to heat the hot tank, thus increasing the efficiency of the engine relative to a Stirling engine lacking the heat transfer apparatus.
24. 24. The heat transfer apparatus according to claim 1, further comprising a thermal voltaic device having a hot side and a cold side and a voltage output wherein the second container is positioned to cool the cold side, and the first container is positioned to heat the hot side thereby increasing the voltage output relative to a voltage device that lacks the heat transfer apparatus.
25. 25. The heat transfer apparatus according to claim 1, which further comprises a turbine device placed in the conduit between the first and second containers, the device having a turbine rotor capable of converting the linear movement of the working substance as it is adsorbed by the adsorbent material from the second container to the first vessel for rotational movement and transferring energy associated with the rotational movement outside the conduit.
26. 26. The heat transfer apparatus according to claim 1, wherein the first and second containers, conduit and working substance define a first refrigeration unit, further comprising at least one second refrigeration unit having first and second containers connected with a conduit and forming a sealed volume having a working substance therein, the second container of the refrigeration unit being contained within a refrigeration chamber defining a refrigerated volume, the refrigeration units being Controllable to keep the volume cooled to a selected temperature.
27. 27. The heat transfer apparatus according to claim 1, wherein the first container has an internal area and the conduit has a perforated portion that exits in the internal area, the perforated portion having a plurality of perforations of a selected size, for passage of the working substance between the adsorbent and the conduit.
28. 28. The heat transfer apparatus according to claim 27, further comprising a nick layer positioned between the perforated portion and the adsorbent, the nick layer having a plurality of openings, the openings having a size that is smaller than the selected size of the perforations in the perforated portion of the conduit to prevent the adsorbent material from entering the perforations.
29. 29. The heat transfer apparatus according to claim 1, further comprising a cooling chamber that defines an internal area having a temperature, wherein the second container is placed within the internal area of the cooling chamber, the duct it passes through an opening in the refrigerator chamber, and the first container is placed outside the internal area, the heat transfer apparatus capable of reducing the temperature of the internal area below a temperature outside the internal area.
30. 30. The heat transfer apparatus according to claim 1, wherein the second container is a tube length.
31. 31. The heat transfer apparatus according to claim 1, further comprising a plurality of fins projecting outward from an external surface of the second container.
32. 32. The heat transfer apparatus according to claim 1, wherein the amount of working substance is approximately equal to the adsorbent capacity of the adsorbent material.
33. 33.- The heat transfer apparatus according to claim 1, further comprising a heat transfer source for transferring heat between the adsorbent material and a region outside the first container, the source of heat transfer being in thermal contact with the adsorbent material.
34. 34. The heat transfer apparatus according to claim 33, wherein the source of heat transfer is a cooling jacket surrounding the adsorbent material.
35. 35.- The heat transfer apparatus according to claim 33, wherein the source of heat transfer is placed inside the first container.
36. 36. The heat transfer apparatus according to claim 33, wherein the source of heat transfer is capable of cooling the adsorbent material.
37. 37.- The heat transfer apparatus according to claim 33, wherein the source of heat transfer is capable of heating the adsorbent material.
38. 38.- The heat transfer apparatus according to claim 21, wherein the compressible material (42) comprises foam.
39. 39.- The heat transfer apparatus according to claim 21, wherein the second container (6) and compressible material (42) are elongated on a longitudinal axis, the second container (6) having a cross-sectional shape substantially circular when it crosses a * - plane substantially perpendicular to the longitudinal axis, and the compressible material (42) having a substantially triangular cross-sectional shape as it crosses the plane.
40. 40. - The heat transfer apparatus according to claim 21, wherein the compressible material (42) has slots (44) therein positioned to allow the working substance to pass therethrough and through the second container.
41. 41 .- The heat transfer apparatus according to claim 21, wherein the second container (6) has a wall with an internal surface and the compressible material (42) has a surface separated from the inner surface of the wall of the container for allowing the working substance to pass between the surface of the compressible material (42) and the inner surface of the wall of the container.
42. 42. The heat transfer apparatus according to claim 1, wherein the second container (6) has a substantially rigid container wall.
43. 43.- The heat transfer apparatus according to claim 1, wherein the second container (6) has a flexible container wall to allow expansion of the second container when the working substance expands.
44. 44.- A method for transferring heat and a working substance between a first container (4) that contains an adsorbent material (10) and a second container (6) connected to the first container, the two containers that define a sealed volume containing a working substance (26) in a liquid phase, the method comprising: i) allowing a portion of the working substance (26) to vaporize by adsorption and transfer from the second container to the material adsorbent in the first container, thus causing a remaining portion of the work substance to freeze, creating a frozen working substance; and ii) further adsorbing a substantial portion of the frozen working substance (28) by sublimation of the second container (6) to the adsorbent material (10) in the first container (4).
45. 45. - Method according to claim 44, further characterized by the further step of continuing to adsorb the frozen working substance (28) by sublimation of the second container (6) to the adsorbent material (10) in the first container (4) until the frozen working substance (28) is adsorbed substantially completely by the adsorbent material (10).
46. 46. Method according to claim 44, further characterized by the steps of heating the adsorbent material to drive the working substance (26) in a vapor state of the adsorbent material (10) to the second container (6), and condense the working substance from a vapor state to a liquid state in the second container (6).
47. 47. A container assembly, comprising: a container having a container wall, the container wall having a flash pressure limit; and a compressible material (42) placed inside the container, the compressible material having an external surface and defining a cavity therebetween, the compressible material being compressible between a first volume when a substance in the cavity is in a liquid state and a second volume when a substance in the cavity is in a solid state, the second volume being less than the first volume, a pressure inside the container being less than the flash pressure limit when the substance is in the solid state and the material compressible has its second volume.
48. 48. The assembly according to claim 47, further characterized by a substance placed in the cavity, the substance having a first volume of substance when it is in a liquid state and a second volume of substance when it is in a solid state, the second volume of substance being larger than the first volume of substance.
49. 49. The assembly according to claim 48, wherein the substance comprises water.
50. 50.- The assembly according to claim 47, wherein the container comprises a conduit having an opening therethrough positioned for transporting the substance therethrough.
51. 51. The assembly according to claim 50, wherein the compressible material (42) has slots (44) thereon positioned to allow the substance to pass therethrough and through the container.
52. 52. The assembly according to claim 50, wherein the container wall has an internal surface, and the compressible material has a surface separated from the inner surface of the container wall to allow the substance to pass between the surface of the container. compressible material (42) and the inner surface of the container wall.
53. 53. The assembly according to claim 47, wherein the compressible material (42) is foam.
54. 54. The assembly according to claim 47, wherein the container wall is substantially rigid.
55. The assembly according to claim 47, wherein the container wall is flexible to allow expansion of the container stop when the substance expands.
56. The assembly according to claim 47, wherein the container and the compressible material (42) are elongated on a longitudinal axis, the container having a substantially circular cross-sectional shape when it crosses a plane substantially perpendicular to the axis longitudinal, and the compressible material having a substantially triangular cross-sectional shape as it crosses the plane.
57. 57. The assembly according to claim 47, wherein the container wall is thermally conductive to transfer heat between the container and a region external to the container.