WO2019204339A1 - Séparateur de phase et re-saturateur de liquide pour refroidissement à deux phases - Google Patents

Séparateur de phase et re-saturateur de liquide pour refroidissement à deux phases Download PDF

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Publication number
WO2019204339A1
WO2019204339A1 PCT/US2019/027724 US2019027724W WO2019204339A1 WO 2019204339 A1 WO2019204339 A1 WO 2019204339A1 US 2019027724 W US2019027724 W US 2019027724W WO 2019204339 A1 WO2019204339 A1 WO 2019204339A1
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WO
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Prior art keywords
liquid
condenser
chamber
vapor
saturation
Prior art date
Application number
PCT/US2019/027724
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English (en)
Inventor
Steven G. Schon
Original Assignee
Qcip Holdings, Llc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Qcip Holdings, Llc filed Critical Qcip Holdings, Llc
Publication of WO2019204339A1 publication Critical patent/WO2019204339A1/fr

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B23/00—Machines, plants or systems, with a single mode of operation not covered by groups F25B1/00 - F25B21/00, e.g. using selective radiation effect
    • F25B23/006—Machines, plants or systems, with a single mode of operation not covered by groups F25B1/00 - F25B21/00, e.g. using selective radiation effect boiling cooling systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B39/00—Evaporators; Condensers
    • F25B39/04—Condensers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D3/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium flows in a continuous film, or trickles freely, over the conduits
    • F28D3/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium flows in a continuous film, or trickles freely, over the conduits with tubular conduits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2339/00—Details of evaporators; Details of condensers
    • F25B2339/04—Details of condensers
    • F25B2339/044—Condensers with an integrated receiver
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/0061—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for phase-change applications
    • F28D2021/0063—Condensers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2260/00—Heat exchangers or heat exchange elements having special size, e.g. microstructures
    • F28F2260/02—Heat exchangers or heat exchange elements having special size, e.g. microstructures having microchannels

Definitions

  • This disclosure relates to two-phase fluid heat exchangers in which a fluid is vaporized to remove heat, including micro- and mini-channel two-phase exchangers that are to provide a cooling effect for heat sources with high heat fluxes.
  • Fluid heat exchangers are used to remove waste heat from high-heat flux heat sources (typically in excess of 5 watts/cm , and often substantially higher) and devices by accepting and dissipating thermal energy therefrom.
  • high-heat flux heat sources and devices include microelectronics such as microprocessors and memory devices, solid-state light emitting diodes (LEDs) and lasers, insulated-gate bipolar transistor (IGBT) devices such as power supplies, photovoltaic cells, radioactive thermal generators and fuel rods, internal combustion engines.
  • the fluid heat exchangers dissipate heat by thermally conducting the heat into internal passages of the exchanger, through which coolant fluid flows, absorbing the heat conducted across the walls of the exchanger, and the fluid is then transported outside the exchanger, where the heat is rejected to an external heat sink.
  • the coolant fluid flowing through the exchanger may be a gas, it is generally preferable to use a liquid, as liquids have higher heat capacities and heat transfer coefficients than gases.
  • the liquid may remain single phase, or the liquid may partially or completely evaporate within the internal passages of the exchanger.
  • the flow of coolant liquid fed to the fluid heat exchanger may be driven by a pump, or by natural convection due to density differences and/or elevation between the incoming and exiting fluid (e.g. thermosyphons), or by capillary action in the internal passages of the exchanger or their communicating piping, or by a combination of these mechanisms.
  • a pump or by natural convection due to density differences and/or elevation between the incoming and exiting fluid (e.g. thermosyphons), or by capillary action in the internal passages of the exchanger or their communicating piping, or by a combination of these mechanisms.
  • Evaporator-type exchangers rely on the boiling mode, and have the advantages of higher heat transfer coefficients (better heat transfer) per unit of fluid flow rate of the coolant fluid, and also require much less coolant flow, as the majority of the heat is absorbed via the latent heat of vaporization of the boiling fluid, rather than via the sensible heat (heat capacity) of a single-phase liquid or gas.
  • the thermal performance and efficiency of the fluid heat exchangers are greatly enhanced if the internal passages are comprised of microchannels, i.e. having cross-sections with a smallest dimension of less than 1000 microns, and more typically, in the range of 50 - 500 microns.
  • Evaporative-type coolers typically operate as a closed loop, with liquid entering the evaporator, and a two-phase mixture (vapor and saturated liquid) exiting the evaporator. (It is not generally desirable for all of the liquid to vaporize within the evaporator, as this can lead to dry-out and reduced heat transfer towards the outlet of the cooler, resulting in localized high temperatures / hot spots in the devices in contact with and being cooled by evaporative cooler).
  • the two-phase mixture is sent to a condenser, where the vapor is condensed back to liquid, and the (combined) liquids are returned to the evaporative cooler.
  • the circulation of the boiling fluid may be driven by various means, including but not limited to pumping, natural convection due to density differences (thermosyphon effect), capillary action, gravity flow, and various combinations thereof.
  • pumping natural convection due to density differences (thermosyphon effect), capillary action, gravity flow, and various combinations thereof.
  • the invention features apparatus for minimizing sub-cooling of condensed working fluid returning to one or more parallel two-phase coolers that operate in closed-loop circulation mode.
  • the two-phase mixture exiting the one or more coolers is sent to a chamber in which the vapor is separated from the saturated liquid emerging from the liquid, and the vapor is sent to one or more condensers where the vapor is fully condensed back to saturated liquid, which may then be further sub-cooled.
  • the condensed liquid is returned to the separation chamber.
  • the mixing and contacting of sub-cooled condensate with the incoming vapor and saturated liquid in the chamber re heats the condensate by using the latent heat of condensation of the vapor, preferably substantially to its saturation temperature.
  • a portion of the incoming vapor pre-condenses at its saturation temperature, and the net condensed liquid withdrawn from the chamber and returned to the evaporative cooler, preferably at substantially its saturation temperature.
  • the two-phase evaporative coolers can be of the mini- or micro- channel type, with internal passages comprising the active boiling surfaces have hydraulic diameters of less than 1000 microns.
  • the two-phase mixture from the evaporative coolers of Claim 1 of enters the saturation chamber of Claim 1 above the surface of the liquid, so that the (saturated) liquid disperses into droplets which fall onto to the liquid surface, while the vapor disengages and exits to the condenser inlet from above the liquid surface.
  • the two-phase mixture from the evaporative coolers can enter the saturation chamber below the surface of the liquid, so that the liquid mixes with the liquid in the chamber, while the vapor separates and bubbles up to and emerges from the liquid surface, and then exits to the condenser inlet from above the liquid surface.
  • the condensate can return above the surface of the liquid in the saturation chamber, so that the liquid disperses into droplets, and falls through and contacts the vapor in the chamber.
  • a liquid seal-leg may optionally be used to prevent vapors from being sucked back up into the condensate outlet line.
  • the condensate can return below the surface of the liquid in the saturation chamber, so that so that the liquid mixes with and absorbs heat from saturated liquid in the chamber.
  • the condensate return line can be oriented to promote turbulence in the liquid volume and especially to promote waves or frothing action at the surface, to promote contacting and heat transfer between the liquid and vapor in the chamber.
  • the condenser may be arranged to provide a top-to-bottom flow pattern, with the vapor entering an upper side of the condenser, and the condensate exits by gravity from a lower outlet side of the condenser.
  • the condenser may be oriented substantially horizontally, with working fluid side of the condenser configured in a single-pass or multi-pass down-flow
  • the condenser may be oriented substantially vertically or inclined, with working fluid side of the condenser configured in a single-pass down-flow arrangement.
  • the condenser may be arranged as a“knock-back” condenser, i.e. with the vapor entering and the liquid counter-currently and substantially co-axially exiting by gravity via the underside of the condenser.
  • the saturation chamber may be formed from piping arranged as an tee elevated above the liquid surface, for separating the incoming two-phase mixture from the evaporative coolers and a second tee below the liquid surface, to mix the condensate with the liquid being separated from the incoming two-phase mixture.
  • the saturation chamber may be formed from piping arranged as a cross elevated above the liquid surface, where the incoming two-phase mixture from the evaporative coolers of Claim 1 impinges on, contacts with, and then separates from the condensate returning from the condenser via the sides of the cross, with the vapor exiting to the condenser from the top of the cross, and the net liquid exits via the bottom of the cross.
  • the condenser can be arranged to provide a top-to-bottom flow pattern, wherein the two-phase mixture enters an upper side of the condenser, with the condensate exiting by gravity from a lower outlet side of the condenser.
  • the condenser can be configured for self-venting flow, with the passages where the condensation takes place being sufficiently large such that the condensate does not fully fill the cross sections of the passages, thereby allowing any condensed liquid exiting the condenser to pressure-equalize with the incoming two-phase mixture and thereby remain saturated.
  • the self- venting condenser passages can also serve as the saturation chamber.
  • the liquid transfer line between the saturation chamber and the evaporative coolers can be made from materials with low thermal conductivity and/or are thermally insulated.
  • the pressure differential between the saturation chamber and the evaporative coolers can be minimized by operating the cooling loop as a thermo- syphon, where the circulation is driven by gravity and density differences, and, the elevation difference between the separation chamber and the evaporative cooler can be reduced to the minimum required to ensure adequate circulation without complete vaporization of the fluid in the evaporative cooler.
  • Liquid returning from the saturation chamber to the evaporative coolers that is sub-saturated due to heat looses or pressure increase in the return line can be re-heated by providing a heat exchange means in the immediate vicinity of the inlet to the evaporative cooler, such that heat is transferred from the two-phase mixture exiting the evaporator into sub-saturated liquid returning to the evaporator.
  • the heat may be rejected from the condenser by any convenient means or cooling media that are cooler than the saturation temperature of the working fluid.
  • the invention features a cooling apparatus that includes a heated two-phase evaporator input for receiving a heated two-phase coolant mixture from an output of a two-phase evaporator, a condenser output for providing at least some of the coolant mixture to a at least one condenser, a condenser input for receiving at least some of the received coolant in condensed form from the at least one condenser, and a saturation volume responsive to the heated two-phase evaporator input and to the condenser output, operative to increase the saturation level of the condensed coolant from the condenser, and having an evaporator return output for returning the condensed coolant to an input of the evaporator.
  • the invention features a cooling method that includes receiving a heated two-phase coolant mixture from an evaporator, condensing a first portion of the coolant mixture, using a second portion of the coolant mixture to increase the saturation of the coolant mixture condensed in the step of condensing, and returning the coolant mixture to the evaporator after its saturation has been increased.
  • the various embodiments presented in this application can provide increased cooling efficiency in evaporative microchannel heat exchangers.
  • the thermal performance of two-phase (evaporative) closed-loop coolers can be improved by providing a passive means to re-heat and re saturate sub-cooled working fluid returning from condensers. This is accomplished by providing a chamber to separate the vapor from the saturated liquid emerging from the mixed-phase outlet of the evaporative cooler, sending substantially only the vapor portion to a condenser, and returning the condensed fluid, which may be sub-cooled, to the saturation chamber prior to withdrawing the condensed liquid and returning it to the evaporative cooler.
  • the mixing and contacting of sub-cooled condensate with the incoming vapor and saturated liquid in the chamber re-heats the condensate substantially to its saturation temperature, by using the latent heat of condensation of the vapor. This causes a portion of the incoming vapor to pre condense at its saturation temperature, and has the beneficial effect of reducing the vapor load on the condenser, increasing the effective cooling capacity of the condenser.
  • the mixed liquid in the chamber is substantially at its boiling (saturation) temperature.
  • the net condensed liquid withdrawn from the chamber is preferably at substantially its saturation temperature, and is warmer than any sub-cooled liquid emerging from the condenser.
  • Further reheating / re-saturation of the returning liquid can be achieved by providing a heat exchange means in the immediate vicinity of the inlet to the evaporative cooler, whereby heat is transferred from the two-phase mixture exiting the evaporator, to any liquid returning to the evaporator that may be sub saturated due to heat losses or pressure elevation in the return lines.
  • condensers 18 are typically sized for a maximum heat load, plus an additional margin (safety factor), so that the condensers are over-sized. As a result, the condensers remove more heat than is simply required to re-condense the vapor (latent heat of vaporization). Once all the vapor is condensed, and only liquid remains, the liquid is cooled further, below its boiling point, i.e. the liquid exiting the condenser and returning to the evaporative cooler is sub-cooled, as shown in Figs. 2A-2C.
  • the unexpected increase in the wall temperatures in the vicinity of the sub-cooled zone of the cooler reduces the temperature driving force for removing heat (via conduction through the wall to the fluid), despite the lower fluid temperate of the sub-cooled liquid compared to its temperature in the boiling zone.
  • the higher wall temperatures are attributed to the inferior local heat transfer coefficients where the fluid is single (liquid) phase, compared to the heat transfer coefficients where the fluid is in the boiling regime.
  • sub-cooling can be deleterious to the performance of evaporative coolers, particularly high-performance coolers using mini- or micro-channels.
  • Another option would be control the cooling media to the condensers, to limit or prevent the sub-cooling effect. But this would seem to require some kind of active cooling control means, again adding to the complexity and cost of the system, e.g. for temperature sensors, control solver, and mechanical means (flow or speed throttling) of adjusting the flow of coolant.
  • one or more parallel two-phase (evaporative) coolers operating in closed-loop circulation mode, in which the two-phase mixture exiting the one or more coolers is sent to a chamber, and in which the vapor is separated from the saturated liquid emerging from
  • the vapor is sent to one or more condensers where the vapor is fully condensed back to saturated liquid, which may then be further sub-cooled, and the condensed liquid is returned to the separation chamber.
  • the mixing and contacting of sub-cooled condensate with the incoming vapor and saturated liquid in the chamber re-heats the condensate substantially to its saturation temperature, by using the latent heat of condensation of the vapor. This also causes a portion of the incoming vapor to pre-condense at its saturation temperature, reducing the vapor load on the condenser.
  • the mixed liquid in the chamber is substantially at its boiling (saturation) temperature.
  • the net condensed liquid withdrawn from the chamber and returning to the evaporative cooler is warmer than any sub-cooled liquid emerging from the condenser.
  • Various configurations may be employed for supplying and returning the various streams to and from the condensers and the saturation chambers. These include, but are not limited to:
  • the two-phase mixture from the evaporative cooler enters the saturation chamber above the surface of the liquid, so that the (saturated) liquid disperses into droplets which fall onto to the liquid surface, while the vapor disengages and exits to the condenser inlet from above the liquid surface.
  • the two-phase mixture from the evaporative cooler enters the saturation chamber below the surface of the liquid, so that the (saturated) liquid mixes with the liquid in the chamber, while the vapor separates and bubbles up to and emerges from the liquid surface, and then exits to the condenser inlet from above the liquid surface.
  • a liquid seal-leg may optionally be used to prevent vapors from being sucked back up into the condensate outlet line (due to difference in vapor pressures of the sub-cooled liquid in the condenser and saturated liquid in the chamber).
  • the condensate return line may be oriented to promote turbulence in the liquid volume and especially to promote waves or frothing action at the surface, to promote contacting and heat transfer between the liquid and vapor in the chamber.
  • the working fluid side of the condenser may be configured in a single -pass or multi pass arrangement.
  • the saturation chamber may be formed from piping arranged as a tee elevated above the liquid surface, for separating the incoming two-phase mixture from the evaporative cooler, and a second tee below the liquid surface, to mix the condensate with the liquid being separated from the incoming two-phase mixture.
  • the saturation chamber may be formed from piping arranged as a cross elevated above the liquid surface, where the incoming two-phase mixture from the evaporative cooler impinges on, contacts with, and then separates from the condensate returning from the condenser via the sides of the cross, with the vapor exiting to the condenser from the top of the cross, and the net liquid exits via the bottom of the cross.
  • the condenser is configured to be“self-venting”, i.e. the passages where the condensation takes place are sufficiently large such that the condensate does not fully fill the cross sections of the passages, thereby allowing any condensed liquid exiting the condenser to pressure-equalize with the incoming two-phase mixture and thereby remain saturated.
  • the condenser passages also serve as saturation chambers.
  • the working fluid side of the condenser may be configured in a single -pass or multi pass arrangement.
  • One advantage of embodiments of the present invention is that they can passively facilitate the re-heating of sub-cooled condensate to return it to the saturation temperature, without requiring external heating means or controls. They can also reduce the volume of vapor entering the condensers, thereby increasing the available cooling capacity of the condensers, so that they can handle higher heat loads from the evaporative coolers.
  • the saturation chamber can serve as a reservoir for the working fluid, and can accommodate changes in fluid volume due to thermal expansion effects at different operating temperatures.
  • Fig. 1A is a first compound figure showing local boiler temperature measurements plotted against temperature, reproduced from Fig. 7 of the Zuk et al. paper;
  • Fig. 1B is a second figure showing local boiler temperature measurements plotted against temperature, reproduced from Fig. 11 of the Zuk et al. paper;
  • Fig. 2A is a schematic view of a first conventional condenser arrangement in which there is a direct return from a condenser;
  • Fig. 2B is a schematic view of a second conventional condenser arrangement in which there is an external reservoir
  • Fig. 2C is a schematic view of a third conventional condenser arrangement in which a condenser serves as a reservoir;
  • Fig. 3 is a schematic view of a first embodiment according to the invention in which there is an above-surface two-phase inlet and condensate return;
  • Fig. 4 is a schematic view of a second embodiment according to the invention in which there is a sub-surface two-phase inlet and condensate return;
  • Fig. 5 is a schematic view of a third embodiment according to the invention in which there is an above-surface two-phase inlet and sub-surface condensate return;
  • Fig. 6 is a schematic view of a fourth embodiment according to the invention in which there is a sub-surface two-phase inlet and sub-surface condensate return;
  • Fig. 7 is a schematic view of a fifth embodiment according to the invention in which there is an above- surface two-phase inlet and condensate return with seal-leg;
  • Fig. 8 is a schematic view of a sixth embodiment according to the invention in which there is a sub-surface two-phase inlet and condensate return with seal-leg;
  • Fig. 9 is a schematic view of a seventh embodiment according to the invention in which there is an above- surface two-phase inlet and knock-back condenser;
  • Fig. 10 is a schematic view of an eighth embodiment according to the invention in which there is a sub-surface two-phase inlet and knock-back condenser;
  • Fig. 11 is a schematic view of a ninth embodiment according to the invention in which there is a bottom two-phase inlet and outlet of knock-back condenser;
  • Fig. 12 is a schematic view of a tenth embodiment according to the invention in which there are two piping tees as saturation chamber;
  • Fig. 13 is a schematic view of an eleventh embodiment according to the invention in which there is a piping cross as saturation chamber;
  • Fig. 14 is a schematic view of a twelfth embodiment according to the invention in which there is a top-entering self-venting condenser and tubes that keep condensate at saturation, with a condenser outlet serving as reservoir;
  • Fig. 15 is a schematic view of a thirteenth embodiment according to the invention in which there is a self-venting condenser with external phase separator riser and tubes that keep condensate at saturation, with a condenser outlet serving as reservoir; and
  • Fig. 16 is a schematic view of a fourteenth embodiment according to the invention in which there is a top-entering self-venting multi-pass condenser and tube that keep condensate at saturation, with a condenser outlet pipe serving as reservoir.
  • one or more parallel two-phase (evaporative) coolers 14 operate in closed-loop circulation mode, in which a two-phase mixture 16 exiting the one or more coolers is sent to a saturation chamber 38, where the saturated vapor 36 is separated from the saturated liquid 21 emerging from the liquid.
  • the vapor is sent to one or more condensers 18 where the vapor is fully condensed back to saturated liquid by a coolant 22, 24, and the saturated liquid may then be further sub-cooled. This condensed liquid is returned to the separation chamber 38.
  • the mixing and contacting of sub-cooled condensate with the incoming vapor and saturated liquid in the chamber re-heats the condensate substantially to its saturation temperature, by using the latent heat of condensation of the vapor, and a portion of the incoming vapor pre-condenses at its saturation temperature.
  • the net condensed liquid 21 is withdrawn from the chamber and returned to the evaporative cooler 14 at substantially its saturation temperature.
  • the two-phase mixture from the evaporative cooler 14 enters the saturation chamber 38 above the surface of the liquid, so that the (saturated) liquid disperses into droplets 32 which fall onto to the liquid surface, while the vapor disengages and exits to the condenser inlet from above the liquid surface.
  • the two-phase mixture from the evaporative cooler enters the saturation chamber 38 below the surface of the liquid, so that the (saturated) liquid mixes with the liquid in the chamber, while the vapor separates and forms bubbles 33 that rise up to and emerge from the liquid surface, and then exit to the condenser inlet from above the liquid surface.
  • the condensate can also return above the surface of the liquid in the saturation chamber, so that the (sub-cooled) liquid disperses into droplets 32, and falls through and contacts the vapor 36 in the chamber.
  • a liquid seal-leg 40 may optionally be used to prevent vapors from being sucked back up into the condensate outlet line (due to difference in vapor pressures of the sub-cooled liquid in the condenser and saturated liquid in the chamber).
  • the condensate returns below the surface of the liquid in the saturation chamber, so that so that the (sub-cooled) liquid mixes with and absorbs heat from saturated liquid in the chamber.
  • the condensate return line may be oriented to promote turbulence in the liquid volume and especially to promote waves or frothing action at the surface, to promote contacting and heat transfer between the liquid and vapor in the chamber.
  • the condenser is arranged as a“knock-back” condenser 48, i.e. with the vapor entering and the liquid counter-currently and substantially co axially exiting by gravity via the underside of the condenser.
  • the saturation chamber may be formed from piping arranged as a first tee 50 elevated above the liquid surface, for separating the incoming two- phase mixture from the evaporative cooler, and a second tee 52 below the liquid surface, to mix the condensate with the liquid being separated from the incoming two-phase mixture.
  • the saturation chamber may be formed from piping arranged as a cross 54 elevated above the liquid surface, where the incoming two-phase mixture from the evaporative cooler impinges on, contacts with, and then separates from the condensate returning from the condenser via the sides of the cross, with the vapor exiting to the condenser from the top of the cross, and the net liquid exits via the bottom of the cross.
  • the condenser 58 is arranged to provide a top-to-bottom flow pattern, where the two-phase mixture enters an upper side of the condenser, and the condensate exits by gravity from a lower outlet side of the condenser.
  • the condenser is configured to be“self-venting”, i.e. the passages 62 where the condensation takes place are sufficiently large such that the condensate does not fully fill the cross sections of the passages, thereby allowing any condensed liquid exiting the condenser to pressure-equalize with the incoming two-phase mixture and thereby remain saturated.
  • the condenser passages also serve as saturation chambers.
  • the working fluid side of the condenser may be configured in a single-pass or multi-pass arrangement.
  • the potential for sub-cooling of the liquid returning to the evaporative cooler from the saturation chamber is minimized by minimizing heat losses in the transfer line, e.g. using thermally non-conductive or insulated lines
  • the potential for sub-cooling of the liquid returning to the evaporative cooler from the saturation chamber is minimized by minimizing the pressure elevation between the separation chamber and the evaporative cooler. This is preferably
  • thermo-syphon where the circulation is driven by gravity and density differences, rather than pumping the liquid to the evaporative cooler.
  • the elevation difference [liquid pressure head] between the separation chamber and the evaporative cooler is reduced to the minimum required to ensure adequate circulation.
  • further reheating / re saturation of the returning liquid can be achieved by providing a heat exchange means in the immediate vicinity of the inlet to the evaporative cooler, whereby heat is transferred from the two- phase mixture exiting the evaporator, back to the sub-saturated liquid returning to the evaporator.
  • a riser 64 can be placed upstream of the condenser 58 to separate vapor from the two-phase flow and direct it to the top of the condenser while combining the separated liquid with the liquid exiting the condenser.
  • the condenser 68 is arranged to provide a top- to-bottom flow pattern, where the vapor enters an upper side of the condenser, and the condensate exits by gravity from a lower outlet side of the condenser, such as through a serpentine path 70.
  • the working fluid side of the condenser may be configured in a single-pass or multi-pass arrangement.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)

Abstract

Dans un aspect général, l'invention concerne un appareil pour réduire au minimum le sous-refroidissement d'un fluide de travail condensé retournant vers un ou plusieurs refroidisseurs à deux phases parallèles qui fonctionnent en mode de circulation en boucle fermée. Le mélange diphasique sortant du ou des refroidisseurs est envoyé à une chambre dans laquelle la vapeur est séparée du liquide saturé sortant du liquide, et la vapeur est envoyée à un ou plusieurs condenseurs où la vapeur est complètement condensée pour revenir sous forme de liquide saturé, qui peut ensuite être davantage sous-refroidi. Le liquide condensé est renvoyé à la chambre de séparation. Le mélange et la mise en contact du condensat sous-refroidi avec la vapeur entrante et le liquide saturé dans la chambre réchauffent le condensat en utilisant la chaleur latente de condensation de la vapeur, de préférence sensiblement à sa température de saturation. Une partie de la vapeur entrante se condense au préalable à sa température de saturation et le liquide condensé net est retiré de la chambre et renvoyé au refroidisseur par évaporation, de préférence à sensiblement sa température de saturation.
PCT/US2019/027724 2018-04-16 2019-04-16 Séparateur de phase et re-saturateur de liquide pour refroidissement à deux phases WO2019204339A1 (fr)

Applications Claiming Priority (2)

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US201862658260P 2018-04-16 2018-04-16
US62/658,260 2018-04-16

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112954965A (zh) * 2021-02-01 2021-06-11 中国科学院电工研究所 用于高性能计算机的模块化冷却系统
CN113357946A (zh) * 2021-06-09 2021-09-07 上海交通大学 耦合气液两相流引射泵的自驱动热虹吸回路散热装置
KR102671431B1 (ko) 2022-02-07 2024-05-30 (주)연엔지니어링기술사사무소 케스케이드냉각기

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1003015A (en) * 1962-05-31 1965-09-02 Standard Telephones Cables Ltd Cooling systems for thermionic valves
US4047561A (en) * 1974-10-18 1977-09-13 General Electric Company Cooling liquid de-gassing system
SU817419A1 (ru) * 1979-03-28 1981-03-30 Предприятие П/Я А-1665 Испарительна система охлаждени
RU49607U1 (ru) * 2005-06-30 2005-11-27 Верба Владимир Степанович Устройство охлаждения процессора
RU2648803C1 (ru) * 2016-12-12 2018-03-28 Рустем Руждиевич Везиров Способ охлаждения и конденсации парогазовой смеси и смесительная конденсационная система для его осуществления

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1003015A (en) * 1962-05-31 1965-09-02 Standard Telephones Cables Ltd Cooling systems for thermionic valves
US4047561A (en) * 1974-10-18 1977-09-13 General Electric Company Cooling liquid de-gassing system
SU817419A1 (ru) * 1979-03-28 1981-03-30 Предприятие П/Я А-1665 Испарительна система охлаждени
RU49607U1 (ru) * 2005-06-30 2005-11-27 Верба Владимир Степанович Устройство охлаждения процессора
RU2648803C1 (ru) * 2016-12-12 2018-03-28 Рустем Руждиевич Везиров Способ охлаждения и конденсации парогазовой смеси и смесительная конденсационная система для его осуществления

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112954965A (zh) * 2021-02-01 2021-06-11 中国科学院电工研究所 用于高性能计算机的模块化冷却系统
CN113357946A (zh) * 2021-06-09 2021-09-07 上海交通大学 耦合气液两相流引射泵的自驱动热虹吸回路散热装置
KR102671431B1 (ko) 2022-02-07 2024-05-30 (주)연엔지니어링기술사사무소 케스케이드냉각기

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