Fluid phase change thermal management apparatus and method

Abstract

Fluid phase change thermal management cooling method and apparatus for removing heat from a heat source, wherein the method includes filling a cooling chamber having a volume V1 of a fluid phase change thermal management cooling device with a liquid phase fluid; increasing the volume of the cooling chamber to a volume V2 such that substantially only liquid and vapor phase fluid is present in volume V2, thereby vaporizing a portion of the fluid from its liquid phase to its vapor phase; ensuring a residence time to vaporize at least a portion of the liquid phase fluid in contact with a heated surface of the cooling chamber; repeating the above steps, selecting the timing of the steps and the residence time between steps to control heat accumulation within set limits.

Description

[Technical Field]

[0001] The present invention relates to a fluid phase change thermal management apparatus and method or device for providing improved management of unwanted heat transfer away from a target heating area and towards a waste area.

[0002] In particular, the present invention relates to the rapid and efficient removal of heat from a heated area by using the latent heat properties of a cooling fluid that vaporizes at very low pressures. [Background technology]

[0003] Conventional cooling systems facilitate cooling of high temperature regions by circulating a cooling fluid around the heated member, thereby drawing heat from the heated member into the cooling medium, which is then typically transported away from the heat source through channels. Conventional approaches involve connecting such cooling chambers in series or parallel, each of which has drawbacks such as inefficient heat removal, the need for high cooling fluid flow rates, and complex connections between chambers or cavities.

[0004] A known cooling method involves a cooling chamber, a cooling liquid within the chamber, and a space above the cooling liquid that contains substantially only cooling liquid vapor. A drawback of such an arrangement is that the heated area of ​​the cooling chamber dries out through evaporation, requiring further wetting to continue cooling, which is often difficult to achieve.

[0005] Some cooling systems, such as conformal cooling systems for plastic injection molding, offer the advantage of effectively and efficiently transferring heat away from the molding surface of the molded part, which in turn allows the injection molding machine to complete more cycles in a given period of time, resulting in optimal production rates for the molded part. However, conformal cooling systems add complexity and cost to the manufacture of injection molds due to complex mold channel designs that are difficult to design and manufacture.

[0006] Although water is an excellent cooling medium, it has several disadvantages compared to other cooling media. In the presence of air, water can cause corrosion of the mold or cooling system, leading to scale buildup inside the cooling channels. Therefore, in water-cooled molds, which use water flowing through directed channels, maintaining the cooling channels in operational condition is effective to prevent corrosion, which shortens the mold's lifespan. However, the increased inspection requirements increase the costs associated with using these molds and their downtime due to more frequent inspections for preventive maintenance procedures. Computer cooling is also desirable, particularly in facilities where large-capacity computers are located, such as data centers, where each computer can generate a significant amount of heat that can affect the performance of the computer's integrated circuits and central processing units (CPUs). High temperatures within a CPU can cause dynamic frequency scaling, forcing components to slow down by reducing their operating frequency, resulting in reduced performance.

[0007] For low-volume computer CPUs, such as those found in typical desktop personal computers and notebooks, air cooling of the CPU using a fan and cooling fins on an integrated heat sink is adequate. A common cooling method for high-end PCs involves using a fluid-cooled heat sink in close contact with the casing of the CPU and associated electronics.

[0008] Liquid immersion cooling of computer server components is a more advanced technology in which the computer chip / motherboard / CPU and associated electronics are submerged in a thermally conductive dielectric fluid, the fluid comes into direct contact with the electronic components, and heat is then removed from the fluid as it flows over the circuitry and through a heat exchanger.

[0009] It is known that with heat being transferred from a heated area, a cooling fluid is directed to the location requiring heat reduction, where at very low pressure the cooling fluid vaporizes and the heat is transferred as latent heat from the heated area to the vapor phase fluid, which can then be transferred through a heat exchanger / condenser.

[0010] To achieve a working supply of cooling fluid, it is sometimes desirable to transport such fluid through conduits that lead to hot locations. This can create problems when more than one such conduit is needed, for example, in areas where there are several cooling chambers or cavities at various locations and heights relative to one another. When cooling chambers or cavities are at various heights, it is important to be able to control the flow of fluid to each to provide a consistent and uniform supply of cooling medium. When cooling chambers vaporize fluid within them, it is important to remove this vapor from the chamber or cavity and allow for the insertion of new cooling fluid before the fluid dries on the surface.

[0011] Other cooling fluids with lower vapor pressures can address the shortcomings of water, but as fluids, they still face the problem of small, narrow channels or gaps between components or within the cooling fluid pathways. None of them are as environmentally friendly as water. Summary of the Invention

[0012] One form of the invention is a fluid phase change thermal management cooling method comprising: a space defined by a surrounding structure containing a heat source; and a heat exchanger providing vapor condensation; introducing a liquid to a degree that substantially fills the space with the liquid; removing a portion of the liquid so that substantially only a vapor of the liquid, a body of the liquid, and the wetted inner surfaces of the structure are present; then allowing a residence time for at least a portion of the liquid in contact with the heated surface of the surrounding structure to vaporize; and then repeating the steps, selecting the timing of the steps and the residence time between steps to limit heat accumulation to a predetermined degree.

[0013] A further aspect of the invention is a fluid phase change thermal management device or system having a cooling chamber containing a body of cooling fluid, a pressure controller for controlling the fluid pressure within the cooling chamber, and means for condensing vapor, the method including filling the chamber with liquid coolant with the pressure controller, then extracting a portion of the coolant in a manner to leave substantially only coolant vapor in the space so that heat transfer occurs as a substantially isothermal process, then after a residence time, allowing the coolant to vaporize to at least some extent, then refilling the chamber with liquid coolant, and repeating these steps sufficiently and rapidly to limit temperature fluctuations of surfaces within the chamber to a predetermined extent.

[0014] The controlled cycling of the chamber state from filled with liquid coolant to partially emptied but with substantially only coolant vapor means that when the chamber is refilled, any residual vapor possibly trapped in the intricate geometry and smaller tubes that may be features of the geometry requiring cooling can be pushed out or condensed by the pressure used to cause the filling.

[0015] This means that the coolant can be applied directly to the surface requiring cooling and the unquestionable efficiency of substantially isothermal heat transfer can be achieved.

[0016] The chamber is defined by a surrounding structure capable of withstanding the resulting pressure fluctuations, including any ancillary components such as conduits that act as a closed path between the pump and the chamber.

[0017] Preferably, the cooling fluid occupies all of the cooling chamber.

[0018] However, the cooling chamber may be described in another way, such as when it is part of a structure that defines a space that includes a closed volume in a functional sense and a volume that varies with the relative position of a piston or other active component of the pressure control means, such that the space can be described as having a first mode in which the cooling liquid substantially fills the space, and a second mode that is larger than the first mode in which there is space filled substantially only with liquid vapor, and the method of the present invention is to repeatedly cycle between the two modes.

[0019] Accordingly, the present invention can be described as a fluid phase change thermal management cooling method in which there is an adjustable space defined by a surrounding structure and including a heat source to be cooled, a body of liquid, and a heat exchanger providing vapor condensation, the space being adjustable to a first adjustment mode in which it is substantially filled with the body of liquid, and a second adjustment mode in which it has a surplus space substantially filled only with vapor of the liquid, and the method of the present invention is repeatedly transitioned between the two modes.

[0020] Preferably the pressure control means is a pump means which uses pressure to change the state of the space from a smaller size mode to a larger size mode, substantially relative to atmospheric pressure.

[0021] Preferably, the volume of the cooling chamber is , pressure Including the volume of the force control means These are collectively referred to as the system volume. .

[0022] Preferably, the pressure control means changes the volume of the cooling chamber or system volume from Volume 1 (V1) to Volume 2 (V2), where V1 <V2である)。

[0023] Preferably, the pressure control means is a pressure pump.

[0024] Preferably, the pressure control means is a piston pump, movement of the piston changing the volume, the piston being capable of assuming two positions, wherein in a retracted position the piston together with the closed circuit and main chamber provides a second or larger size mode state having volume V2, and when released it collapses to define a first mode or smaller size state having volume V1.

[0025] Preferably, the piston pump arrangement includes a main piston pump housing in fluid communication with the cooling chamber.

[0026] Preferably, the main piston pump housing is fluidly connected to the cooling chamber by a conduit that carries fluid therebetween in a closed circuit.

[0027] Preferably, the conduit is a flexible conduit.

[0028] Preferably, the piston pump has a plunger / piston head that is movably actuated by an actuation device, for example a linear actuation device which may be an air cylinder.

[0029] Preferably, biasing means is operably attached to the pressure control means to apply a downward force (pressure P1) to the cooling fluid.

[0030] Preferably, the pressure control means is a positive displacement pump.

[0031] Preferably, the positive displacement pump is a reciprocating positive displacement pump.

[0032] Preferably, operation of the pressure control means increases the volume of the cooling chamber, reducing the pressure of the cooling fluid to P2.

[0033] Preferably, the cooling chamber together with the closed circuit and the pump chamber forms a sealed system.

[0034] Yet another embodiment of the present invention is a fluid phase change thermal management cooling method for removing heat from a heat source, comprising the steps A-D of: A. filling a cooling chamber having a volume V1 of a fluid phase change thermal management cooling device with a fluid in a liquid phase; B. increasing the volume of the cooling chamber to a volume V2 such that substantially only liquid and gas phase fluid is present in the volume V2, thereby vaporizing a portion of the fluid from its liquid phase to its gas phase; C. providing a residence time to vaporize at least a portion of the liquid phase fluid in contact with the heated surfaces of the cooling chamber; and D. Repeating steps A-C, selecting the timing of the steps and the dwell time between steps to control heat buildup within set limits.

[0035] A further embodiment of the present invention is a method for removing heat from an article, comprising supplying a coolant to a cooling chamber through a closed circuit, reducing the pressure in the closed circuit by a pressure control means to vaporize at least a portion of the coolant while forming a space above the coolant containing substantially only refrigerant vapor, then allowing the vaporized coolant to flow to a condensation region / zone, and then activating the pressure control means to increase the pressure in the closed circuit at least sufficiently to push out or condense any remaining gas phase coolant, thereby filling all spaces in the cooling chamber with the coolant in its liquid phase.

[0036] A further aspect of the present invention is a fluid phase change thermal management device including a pressure control means, a condenser, a cooling chamber in fluid communication with the pressure control means and the condenser, a liquid coolant substantially filling the cooling chamber, and the pressure control means operable to cause a pressure change in the liquid cooling fluid in the cooling chamber from a first pressure P1 to a second pressure P2, causing a portion of the liquid coolant to vaporize.

[0037] A further aspect of the present invention is a fluid phase change thermal management cooling method in which there is an adjustable space defined by a containment structure and including a heat source to be cooled, a body of a liquefaction chamber, and a heat exchanger thereby providing vapor condensation, the space being adjustable between a first adjustment mode in which it is substantially filled with a body of liquid, and a second adjustment mode in which it has excess space substantially filled only with vapor of the liquid, and the method performs steps of repeatedly transitioning between the two modes.

[0038] The pressure control unit is actuated to alternately select between partially reducing the pressure in the closed circuit and at least partially increasing the pressure in the closed circuit to provide the surface requiring cooling with retention of wetness for a time sufficient to maintain a predetermined degree of temperature fluctuation.

[0039] In certain embodiments of the present invention, the sections or portions of the cooling chamber are constructed or made from a material composition having a high thermal conductivity, which may include steel, copper or aluminum or other suitable materials.

[0040] In other particular embodiments, the coolant material is a fluid material suitable for use in a thermal management or cooling system.

[0041] Preferably, the coolant is selected from at least one of the group of coolants such as water, hydrocarbon-based coolants, and specialty fluids that are safe for use directly on electronic components.

[0042] In some embodiments of the thermal management device, system or method, there are multiple cooling chambers.

[0043] Preferably, the pressure control means is connectable to an external power source.

[0044] Preferably the condensation region / zone comprises a condenser device suitable for condensing a refrigerant.

[0045] Preferably, the condenser device is incorporated as part of the cooling chamber.

[0046] In certain embodiments of the present invention, the article to be cooled may be a computer chip, motherboard, CPU or other related computer electronic article, a heat-generating engine, plastic molding equipment, particularly molds used in injection molding systems where heat needs to be removed from the system to reduce cycle times.

[0047] In other embodiments, the invention may include more than one pump, for example, several pumps may operate in series to generate the required pressure differential and / or frequency of pressure differential. [Brief explanation of the drawings]

[0048] In order that the invention may be better understood, specific embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: [Figure 1] FIG. 1 shows a cross-sectional view of a basic configuration of a phase change thermal management device in a first position where the pressure in the system is at a first pressure. [Figure 2] FIG. 2 is the same view as FIG. 1, with the pressure control means in an actuated position reducing the pressure in the system to a second pressure which is less than the first pressure. [Figure 3] 3 is an enlarged view of the valve in section A in FIG. 2. FIG. 3 is an enlarged view of the valve in section B in FIG. [Figure 4] FIG. 4 is an enlarged view of the condenser section as a separate module relative to the main body. DETAILED DESCRIPTION OF THE INVENTION

[0049] The terms "pressure control means," "pump means," "vacuum means," and "pressure differential means," as used throughout this application, refer to mechanisms or means capable of controlling or altering pressure within a system. Such mechanisms may include pump means such as, but not limited to, positive displacement pumps, piston pumps, or other such suitable pumping mechanisms capable of creating a pressure differential in a cooling fluid filling a defined volume or region / zone.

[0050] As used throughout this specification, the terms "first pressure," "first level of pressure," and "P1" refer to a pressure level that is greater than a second pressure.

[0051] As used throughout this specification, the terms "second pressure," "second level of pressure," and "P2" refer to a pressure level below the first or initial pressure.

[0052] The term "latent heat of vaporization" or "heat of vaporization" is the amount of heat that must be added to a quantity of a fluid substance to convert that quantity into a gas.

[0053] As used throughout this specification, the terms "Volume 1," "V1," "Volume 2," and "V2" refer to volumes that can include the sum of the volumes of the cooling chamber and piston chamber and any other fluidly connected volumes, where "Volume 1" and "V1" are less than "Volume 2" and "V2."

[0054] Referring first to FIG. 1, this includes a top plate 25 having an outer surface 26 and an inner surface 27. and Base 30 and a pressure control means 37 which is a linear actuation device which may be, for example, an air cylinder pump applied in molding plastics. management 1 shows a cross-sectional side view of one embodiment of the device 10. FIG.

[0055] In this embodiment, the body 20 includes a cooling chamber 35, which may be defined by a surrounding structure capable of withstanding pressure fluctuations and incorporating a main channel that traverses the entire height of the cooling chamber, oriented vertically. The cooling chamber 35 is defined by the inner surface 27 of the top plate 25 and the inner surface 31 of the base 30 and is filled as completely as possible with liquid coolant. On the outer surface 32 of the base 30 are multiple extensions to the cooling chamber, which typically represent cooling zones / regions located proximate to or within the zone from which heat removal is desired. In FIG. 1 , cores 40 are removably secured to the base 30, each having an internal cavity region 50 that acts as an extension to the cooling chamber. The core 41 has an internal cavity 50 and an outer clearance portion 42, the internal cavity of which is very narrow and fluidly connected to the internal cavity 50.

[0056] Each internal cavity 50 of each core (40 or 41) is fluidly connected to the cooling chamber 35 via an angled secondary channel 70. The channel is shallow and extends upwardly at an upwardly sloping angle away from the internal cavity 50, although secondary channels at other angles are considered within the scope of the present invention. However, in some embodiments, an upwardly extending, angled secondary channel 70 is advantageous.

[0057] A pressure control means 37 is fluidly connected to the flow path of the cooling chamber 35 .

[0058] The pressure control means 37 is, in this embodiment, a reciprocating positive displacement pump that includes a piston head 80 operably connected to a shaft 82, which in turn is operably connected to an actuator mechanism 90 mounted on a surface 91. The pressure control means 37 includes a main housing 85 within which the piston head 80 is closely secured such that the sides of the piston head 80 seal tightly against the interior side walls of the housing 85. A conduit 90 fluidly connects a chamber 87 of the housing 85 with the cooling chamber 35.

[0059] Actuation of actuator 90 urges shaft 82 and piston head 80 upward and away from base 89 of housing 85, increasing the volume of the system from V1 to V2 and thus generating a pressure decrease on the cooling fluid within cooling chamber 35 and on the fluidly connected internal cavities 50 of cores 40 and 41. When the cooling fluid substantially completely fills the internal volume of the chamber of phase change thermal management device 10, the pressure decrease is applied to all surfaces. When actuator 90 is actuated, shaft 82, and therefore piston head 80, is actuated in a reciprocating motion, causing piston head 80 to alternate between a first position that applies a force to the cooling fluid, pushing it out of chamber 87 or resting it on the surface of the fluid within chamber 87, and a second position that draws the cooling fluid into chamber 87.

[0060] In a first position, at volume V1, the pressure in the system is assumed to be P1. When the piston head 80 is raised into the main pump housing 85 towards a second position to a volume V2 greater than V1, this then acts to reduce the pressure in the system, drawing the cooling fluid in the system into the main pump housing 85, thus causing a reduction in pressure in the system, designated as P2. In the present invention, P1 > P2.

[0061] A cooling fluid, such as water, is disposed within the system 10, although other cooling media are contemplated within the scope of the present invention. The cooling fluid fills the entire cooling chamber 35, including the interior cavities 50 of the cores 40 and 41.

[0062] 1, the internal pressure of the system, including cooling chamber 35, the internal cavity of core (40 and 41), and chamber 87 of housing 85, is a first pressure P1. This pressure is generated when piston 80 is in the down position, forcing any gas / liquid in chamber 87 outward, through conduit 90, and into cooling chamber 35, and the pressure can be as high as necessary for safe and effective operation.

[0063] 2, during operation, the system activates actuator 90 to retract piston head 80 into main piston pump housing 85, thus increasing the internal volume of the system (also referred to as system volume), including cooling chamber 35 and piston pump chamber 87. Because it is a closed-path system, the increase in system volume from first volume V1 to second volume V2 immediately reduces the pressure of the cooling fluid from an initial starting pressure P1 to a lower pressure P2 across all interior surfaces of internal cavity 50 of core 40 and within body chamber 35 through secondary connecting channel 70.

[0064] When an article is heated, for example, in an operating injection molding apparatus, heat is generated within the mold body and molding surfaces 100 throughout the molding cycle, and thermal energy is transferred through the cooling core 40 into the cooling fluid within the internal cavity 50. A drop in pressure affects all connected internal surfaces, thus reducing the cooling fluid pressure at the surfaces where heat is being generated, causing the thermal energy in the cooling fluid to be immediately converted into latent heat of vaporization, "boiling" the cooling fluid within that cavity, and the resulting vapor rises toward the condenser 110 where it is converted back to its liquid phase.

[0065] Once the refrigerant vapor is condensed by the condenser 110, it passes through a return conduit (not shown) and is reintroduced at the lower end of the cooling chamber 35. As the pressure in the system drops to P2 and the cooling fluid begins to vaporize, the effect is an isothermal process in which the vaporizing refrigerant removes heat from the cooling chamber without affecting the temperature of the refrigerant. The resulting vaporized refrigerant is then drawn from the internal cavity 50 of the core 40 through the angled secondary connecting channels 70 of the cooling chamber 35, where it can travel to the condenser and reform back into liquid-phase refrigerant.

[0066] In some embodiments, a condenser 110 may be present in a condensing section 120 located, for example, at the upper end of the cooling chamber 35 105 to facilitate condensation of the cooling fluid.

[0067] At the end of the period in which piston head 80 is withdrawn into the main piston pump housing, actuator 90 is again activated, forcing piston head 80 toward end 89, thus reducing the total volume within the system and thereby increasing the pressure within the system and the vaporized refrigerant fluid sufficiently to condense from the gas phase back to the liquid phase.

[0068] The actuator 90 can be controlled by a computer to activate a desired number of cycle times per unit time, with the change of the piston head 80 from the first position shown in Figure 1 to the second position shown in Figure 2 being a single cycle. For example, in certain circumstances, the actuator cycle time may affect the movement of the piston head 80 between its first and second positions having a period of time (e.g., 5 seconds): cooling flow On the body The pressure P1 ; Changing the system volume from V1 to V2 and reducing the pressure (turning on the pump to apply a pulling force to the cooling fluid); Coolant expansion time is 1 second, the pressure of the cooling fluid drops to P2; With a residence time of 3 seconds, the pressure of the cooling fluid is P2; The pressure returns to normal, the system volume changes from V2 to V1, and the cooling fluid pressure rises to P1 in 1 second.

[0069] If desired, the cycle time may be operationally controlled to increase or decrease to a set number of times as required by the application. With each cycle of the pressure control means 37, as the pressure in the system decreases, the coolant within the internal cavity 50 of the core 40 or elsewhere in the system that has absorbed heat vaporizes, thereby removing the heat.

[0070] In some embodiments, a valve mechanism 160 can be disposed on the body 20 in communication with the cooling chamber 35 via the channel 47, the valve mechanism 160 including a float valve 170 in the chamber 180 having needle protrusions 190 and 191 axially aligned and shaped to fit within needle valve seats 192 and 193, respectively. As the float valve body 170 rises upward within the chamber 180, the upper needle 190 engages the needle valve seat 192, and as the float valve body 170 descends within the chamber 180, the lower needle 191 engages the needle valve seat 193. This valve mechanism provides a bleed point that can also act as an airlock assembly, such that as pressure in the system increases, the valve is moved upward to seat the needle 190 within the needle seat 192. This serves to provide a vent for air within the cooling chamber and associated space within the surrounding structure. Air can enter the system through simple air leaks or the release of dissolved air in the liquid coolant. In most situations, this cycling has been found to be sufficient to remove any air contaminants from the vents. In this way, this method is effective in maintaining access to all parts of the heat source and removing heat.

[0071] On the piston head 80 is a piston head valve 200 having a float valve 210 with an interior chamber 212 in fluid communication with the piston chamber 87 by way of a passage 213, a lower needle 215, and a lower needle seat 220. A needle 230 on the float valve 210 extends through an aperture 240. A side port 230 extends through the wall of the piston head valve 200, allowing any fluid that enters the chamber 212 to escape to the space above the piston head 80. This maintains the fluid level and provides an airlock.

[0072] In some embodiments, as shown in FIG. 4, the condenser section 260 is separate from the main body 10 and fluidly connected to the channels of the main body chamber 35 by a conduit 265, or alternatively, is directly coupled to the main body 10, thereby allowing it to be installed and removed as needed for maintenance.

[0073] An air strut or similar biasing means may be attached to the head 80 or shaft 82 of the piston to bias the head 80 back to its original starting position and apply a force to the cooling fluid in the system.

[0074] The fluid phase change thermal management cooling method includes the following steps: - introducing a liquid into the cooling chamber 35 of the fluid phase change thermal management cooling device 100 to a degree that substantially fills the cooling chamber 35 with liquid; - Increasing the volume of the cooling chamber and any fluidly connected chambers (e.g., piston chamber and any connecting conduits); - allowing a residence time to evaporate at least a portion of the liquid in contact with the heated surface of the cooling chamber, and then - Repeating the above steps, selecting the timing of the steps and the dwell time between steps to reduce heat buildup to a set extent.

[0075] The heated surfaces of the cooling chamber 35 are the cores 40 and 41 of the exterior surface 32 of the fluid phase change thermal management cooling device 100, which are exposed and in contact with the heated molding material. The method of filling the cooling chamber 35 with liquid is performed such that the interior surfaces of the cooling chamber 35, including the interior cavities 50 of the cores 40 and 41, are at least substantially wetted.

[0076] Any unwanted gas in the system may be purged by a vent at the top that allows the gas to escape to atmosphere when the piston moves to P1 with the chamber volume reduced to V1.

[0077] As can be seen, the present invention provides a thermal management method and apparatus for cooling a heat source in an efficient manner by reducing the pressure within a cooling chamber so that the cooling fluid, or a portion thereof, vaporizes at low temperatures.

[0078] The thermal management method and apparatus can be used in many situations where heat removal is desirable and uses relatively simple structures and configurations.

[0079] A fluid phase change thermal management cooling method in which there is an adjustable space defined by a containment structure and including a heat source to be cooled, a body of a liquefaction chamber, and a heat exchanger thereby providing vapor condensation, the space being adjustable between a first adjustment mode in which it is substantially filled with a body of liquid, and a second adjustment mode in which it has excess space substantially filled only with vapor of the liquid, the method comprising the step of repeatedly transitioning between the two modes.

[0080] A fluid phase change thermal management cooling method for removing heat from a heat source, comprising the steps A to D of: A. filling a cooling chamber having a volume V1 of a fluid phase change thermal management cooling device with a fluid in a liquid phase; B. increasing the volume of the cooling chamber to a volume V2 such that substantially only liquid and gas phase fluid is present in the volume V2, thereby vaporizing a portion of the fluid from its liquid phase to its gas phase; C. providing a residence time to vaporize at least a portion of the liquid phase fluid in contact with the heated surfaces of the cooling chamber; and D. Repeating steps A-C, selecting the timing of the steps and the dwell time between steps to control heat buildup within set limits.

[0081] ● A fluid phase change thermal management method for removing heat from an item, comprising: supplying a coolant to a cooling chamber through a closed circuit; using a pressure control means to increase the volume in the closed circuit from V1 to V2 to vaporize a portion of the cooling fluid from its liquid phase to its gas phase, whereby substantially only liquid and gas phase fluid are present in volume V2, allowing at least partial vaporization of the cooling fluid from its liquid phase to its gas phase, causing the coolant vapor so produced to flow to a condensation zone; then operating the pressure control means to reduce the volume of the cooling chamber from V2 to V1, thereby at least partially increasing the pressure in the closed circuit, thereby pushing out or condensing any remaining coolant in the gas phase and filling all space in the cooling chamber with coolant in its liquid phase; operating the pressure control means to alternately partially increase the pressure in the closed circuit and at least partially decrease the pressure in the closed circuit, thus converting at least a portion of the coolant from its liquid phase to the gas phase in the condensation zone of the cooling chamber.

[0082] • A fluid phase change thermal management method according to any one of the preceding claims, wherein the pressure pump is a piston pump.

[0083] • The fluid phase change thermal management method as described above, wherein the piston pump includes a main piston pump housing in fluid communication with a cooling chamber.

[0084] • The above fluid phase change thermal management method, wherein the main piston pump housing is fluidly connected to the cooling chamber by a conduit.

[0085] The fluid phase change thermal management method as described above, wherein the conduit is a flexible conduit.

[0086] - The above fluid phase change thermal management method, wherein the piston pump is movably actuated by an actuation device, for example a linear actuation device.

[0087] • A fluid phase change thermal management method according to any one of the preceding, wherein biasing means are operatively attached to the pressure control means to exert a downward force (pressure P1) on the cooling fluid.

[0088] - A fluid phase change thermal management method according to any one of the preceding claims, wherein the pressure on the cooling fluid is reduced to P2 by increasing the volume of the cooling chamber through operation of the pressure control means.

[0089] • A fluid phase change thermal management method according to any one of the preceding claims, wherein the cooling chamber forms a closed system.

[0090] • A fluid phase change thermal management method according to any one of the preceding, wherein the coolant is selected from at least one of the group of coolants such as water, hydrocarbon-based coolants, or mixtures thereof, or special fluids that are safe for use in electronic circuits.

[0091] A fluid phase change thermal management device according to any one of the preceding claims, wherein the pressure control means is connectable to an external power source.

[0092] • A fluid phase change thermal management method according to any one of the preceding claims, wherein the condensation zone comprises a condenser suitable for condensing refrigerant vapor.

[0093] The above fluid phase change thermal management method, wherein the condenser is separate from and in fluid communication with the cooling chamber.

[0094] • A fluid phase change thermal management method according to any one of the above, wherein the article can be a computer chip, a motherboard, a CPU or other related computer electronic article, a heat generating engine, a molding device.

[0095] ● A fluid phase change thermal management device comprising: a pressure control means; a condenser; a cooling chamber in fluid communication with the pressure control means and the condenser; and a liquid coolant substantially filling the cooling chamber, wherein the pressure control means is operable to cause a pressure change in the liquid cooling fluid in the cooling chamber from a first pressure P1 to a second pressure P2, thereby vaporizing a portion of the liquid coolant.

[0096] The above fluid phase change thermal management device, wherein the pressure control means is a pressure pump.

[0097] The above fluid phase change thermal management device, wherein the pressure pump is a piston pump.

[0098] - A fluid phase change thermal management apparatus as described above, wherein the piston pump has a piston head that is movably actuated by an actuation device, for example a linear actuation device.

[0099] - The fluid phase change thermal management device as described above for use in the method.

Claims

1. 1. A fluid phase change thermal management method for removing heat from a heated surface of a fluid phase change thermal management device, the method being carried out using a fluid phase change thermal management device including a containment space with an adjustable size of volume (hereinafter referred to as "system volume"), the method comprising the steps of: A. filling the containment space having a system volume V1 with a coolant in a liquid phase; B. increasing the system volume to V2 so that liquid and gas phase refrigerant are present in the containment space, thereby vaporizing a portion of the refrigerant from the liquid phase to the gas phase; C. ensuring a residence time to vaporize at least a portion of the liquid-phase refrigerant in contact with the heated surface of the device, flowing the vaporized refrigerant into a condensation zone provided in the containment space, and returning the vaporized refrigerant to a liquid-phase refrigerant in the condensation zone; D. Decrease the system volume to V1 and go to step A; and E. Repeating steps A through D, selecting the timing of the steps and the dwell time between steps to control heat buildup within set limits.

2. 1. A fluid phase change thermal management method for removing heat from an item in contact with the cooling zone, the method being carried out using a fluid phase change thermal management device including a containment space having an adjustable size of volume (hereinafter referred to as "system volume") and a cooling zone in contact with the containment space, wherein the containment space is filled with a coolant in a liquid phase when the system volume is V1, the method comprising: increasing the system volume from V1 to V2 using pressure control means to place the containment space in a second regulation mode; wherein in the second adjustment mode, a portion of the refrigerant is vaporizable from a liquid phase to a gas phase, a portion of the liquid-phase refrigerant contacting the cooling zone is vaporized, the vaporized refrigerant flows to a condensation zone provided in the containment space, and returns to the liquid-phase refrigerant in the condensation zone; and reducing the system volume from V2 to V1 using pressure control means to place the containment space in a first regulation mode; wherein in a first adjustment mode, the pressure within said containment space increases, causing any remaining vaporized refrigerant to condense back into liquid phase refrigerant and filling said containment space with liquid phase refrigerant; wherein the pressure control means is operated to alternately increase and decrease the system volume.

3. 3. The fluid phase change thermal management method of claim 2, wherein the pressure control means is a piston pump.

4. the fluid phase change thermal management device includes a device body having the cooling zone, the device body defining a cooling chamber bordering the cooling zone and forming a portion of the containment space; The fluid phase change thermal management method of claim 3 , wherein the piston pump includes a main piston pump housing in fluid communication with the cooling chamber.

5. 5. The fluid phase change thermal management method of claim 4, wherein the main piston pump housing is fluidly connected to the cooling chamber by a conduit.

6. The fluid phase change thermal management method of claim 5 , wherein the conduit is a flexible conduit.

7. The fluid phase change thermal management method of claim 4 , wherein the piston pump has a piston head that is movably actuated by an actuation device.

8. 3. The fluid phase change thermal management method of claim 2, wherein a biasing means is operatively attached to the pressure control means, the pressure control means applying pressure to the coolant by operation of the biasing means.

9. 3. The fluid phase change thermal management method of claim 2, wherein the pressure control means increases the system volume to reduce the pressure on the coolant.

10. A fluid phase change thermal management method according to any one of claims 1 to 9, wherein the containment space forms a closed system.

11. 11. The fluid phase change thermal management method of any one of claims 1 to 10, wherein the coolant is selected from at least one of the group of water, hydrocarbon-based coolants and mixtures thereof, and special fluids safe for use in electronic circuits.

12. 3. The fluid phase change thermal management method of claim 2, wherein the pressure control means is connectable to an external power source.

13. A fluid phase change thermal management method according to any preceding claim, wherein the condensation zone comprises a condenser suitable for condensing vaporized refrigerant.

14. 14. The fluid phase change thermal management method of claim 13, wherein a condenser is detachable from the fluid phase change thermal management device and in fluid communication with the containment space.

15. 3. The fluid phase change thermal management method of claim 2, wherein the article is a computer chip, motherboard, CPU or other related computer electronic article, a heat generating engine, or a molding device.

16. 1. A fluid phase change thermal management device including a containment space with an adjustable size of volume (hereinafter referred to as "system volume"), a pressure control means for adjusting the system volume between V1 and V2 (V1<V2); an apparatus body having a cooling zone, the apparatus body defining a cooling chamber adjacent to the cooling zone and constituting a part of the containment space; a liquid-phase coolant in an amount sufficient to fill the containment space when the system volume is V1; the apparatus body includes a condenser in fluid communication with the cooling chamber; a pressure control means in fluid communication with the cooling chamber and operable to increase a system volume from V1 to V2 to cause a pressure change in the coolant in the cooling chamber from a first pressure P1 to a second pressure P2 (P1>P2) to vaporize a portion of the liquid phase coolant in contact with the cooling zone; A cooling chamber directs vaporized refrigerant to a condenser; A fluid phase change thermal management device in which a condenser converts vaporized refrigerant back into liquid phase refrigerant.

17. 17. The fluid phase change thermal management device of claim 16, wherein the pressure control means is a pressure pump.

18. 20. The fluid phase change thermal management device of claim 17, wherein the pressure pump is a piston pump.

19. The fluid phase change thermal management apparatus of claim 18 , wherein the piston pump has a piston head that is movably actuated by an actuation device.

20. A fluid phase change thermal management device according to claim 16 for use in a method according to any one of claims 1 to 15.

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