A phase change cooling device for high heat flux electronic components and method thereof

Abstract

The application discloses a kind of high heat flow density electronic components phase change cooling device and method thereof, belong to electronic components phase change cooling technical field, device includes liquid tank, water pump, liquid flowmeter, cavitation device, evaporative radiator, vapor-liquid separator, cooler and condenser.Cooling liquid is transported to cavitation device by water pump, and cavitation device makes cooling liquid cavitate and generates micro-nano steam bubble, and micro-nano steam bubble enters evaporative radiator as vaporization crystal seed with cooling liquid, and triggers nucleate boiling heat transfer when electronic components heat;After vapor-liquid mixture is separated by vapor-liquid separator, liquid is cooled by cooler and returns to liquid tank, and gas is condensed by condenser and returns to liquid tank.The application supplies vaporization crystal seed actively, reduces flow instability caused by random nucleation of bubble, and avoids solid particle deposition blockage and static microstructure scouring failure problem, and is suitable for high heat flow density electronic components heat dissipation.

Description

Technical Field

[0001] This invention belongs to the field of phase change cooling technology for electronic components, specifically relating to a phase change cooling device and method for high heat flux density electronic components, which is particularly suitable for heat dissipation of high heat flux density electronic components such as data center CPUs / GPUs and power semiconductors. Background Technology

[0002] With the increasing integration and power density of high heat flux density electronic components such as data center processors, graphics processors, and power semiconductors, the heat flux per unit area has increased significantly. Traditional air cooling methods are limited by the low heat transfer coefficient of air, making it difficult to meet the heat dissipation requirements of high heat flux density areas. Although single-phase liquid cooling can improve heat transfer capacity, it mainly relies on sensible heat transfer, and is still prone to problems such as excessively rapid temperature rise, hot spot accumulation, and insufficient heat dissipation margin when the local heat flux density increases rapidly.

[0003] Phase-change cooling utilizes the vaporization of latent heat in a coolant to remove heat, theoretically offering higher heat transfer capacity and making it suitable for cooling high heat flux density electronic components. However, in actual operation, the boiling heat transfer process is highly dependent on bubble nucleation behavior. Existing phase-change cooling systems typically rely on heating wall defects, micropores, rough structures, or localized overheating to form vaporization nuclei. The location and frequency of bubble formation are highly random, easily leading to unpredictable boiling initiation points, large fluctuations in wall temperature, and unstable vapor-liquid two-phase flow patterns. In severe cases, it may even induce localized drying or boiling crises.

[0004] To improve nucleation conditions, existing technologies employ micro / nano structures such as porous coatings, micropillar arrays, and microgrooves on the evaporation surface to increase the number of static vaporization nuclei. However, once these structures are formed, it is difficult to actively adjust the seed supply according to changes in the thermal load of electronic components. Furthermore, under conditions of high-speed coolant scouring, long-term thermal cycling, or contaminant adhesion, the micro / nano structures may fail or become blocked. Another approach involves adding solid micro / nano particles to the coolant to induce nucleation; however, these solid particles pose a risk of agglomeration, deposition, and blockage of microchannels during long-term cycling, and may alter the coolant properties, affecting system reliability.

[0005] Therefore, existing phase change cooling technologies for high heat flux density electronic components still lack a dynamic vaporization seed supply mechanism that can actively generate, continuously replenish, and transport the seed crystals in the cooling circuit without relying on solid additives, so as to stably trigger nucleation boiling under different heat load conditions and reduce boiling randomness and two-phase flow instability. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a phase change cooling device and method for high heat flux density electronic components, which addresses the shortcomings of the prior art and solves the technical problems of random bubble nucleation, uncontrollable supply of vaporized seed crystals, poor two-phase flow stability, and insufficient long-term operational reliability of static micro / nano structures or solid particle seed crystals in the existing phase change cooling process.

[0007] The present invention adopts the following technical solution: A phase change cooling device for high heat flux density electronic components includes a storage tank, a water pump, a liquid flow meter, a cavitation device, an evaporative radiator, and a vapor-liquid separator, which are connected sequentially along the cooling liquid circulation direction. The liquid outlet of the vapor-liquid separator is connected to the storage tank via a cooler, and the gas outlet of the vapor-liquid separator is connected to the storage tank via a condenser. The cavitation device is used to cavitate the cooling liquid and generate micro-nano vapor bubbles. The micro-nano vapor bubbles serve as vaporization seeds and enter the evaporative radiator with the cooling liquid. The evaporative radiator is used for thermal connection with the high heat flux density electronic components, so that the cooling liquid containing the vaporization seeds undergoes nucleation boiling heat exchange within the evaporative radiator.

[0008] Furthermore, the cavitation device includes any one or a combination of at least two of the following: a venturi tube, a cyclone device, a throttling orifice plate, a heating screen, or an ultrasonic device.

[0009] Furthermore, the cavitation device is a Venturi vortex device, which includes a liquid inlet, a contraction section, a throat, an expansion section, and a liquid outlet connected in sequence, and the expansion section is provided with a vortex structure.

[0010] Furthermore, the Venturi-cyclone device also includes a gas inlet, one end of the gas return branch is connected between the gas outlet of the gas-liquid separator and the condenser, and the other end is connected to the gas inlet. A gas flow meter and a check valve are provided on the gas return branch.

[0011] Furthermore, the cavitation device is a throttling-heating screen device, which includes a throttling orifice plate and a heating screen. The throttling orifice plate is provided with a plurality of throttling orifices, and the heating screen is disposed on the downstream side of the throttling orifice plate.

[0012] Furthermore, the heating screen is thermally connected to the high heat flux density electronic components via a thermally conductive substrate.

[0013] Furthermore, the cavitation device is a Venturi-ultrasonic coupled cavitation device, which includes a Venturi tube and an ultrasonic vibration device disposed on the Venturi tube.

[0014] Furthermore, the evaporative heat sink is provided with a parallel rectangular microchannel array inside, and the wall surface of the evaporative heat sink is connected to a low voltage power supply of no more than 5V so that the wall surface is positively charged.

[0015] Furthermore, it also includes a temperature sensor and a computer. The temperature sensor is respectively installed at the inlet and outlet of the evaporative radiator, and the computer is respectively connected to the liquid flow meter and the temperature sensor. A bypass diversion device communicating with the liquid storage tank is provided on the outlet side of the water pump. The computer is used to adjust the water pump and / or the bypass diversion device according to the detection signals of the liquid flow meter and the temperature sensor.

[0016] Another technical solution of the present invention is a phase change cooling method for high heat flux density electronic components, employing the aforementioned high heat flux density electronic component phase change cooling device, comprising the following steps: The coolant in the storage tank is pumped to the cavitation unit; The cavitation device causes the coolant to cavitate and generate micro-nano vapor bubbles. The coolant containing the micro-nano vapor bubbles is delivered to the evaporative radiator, so that the micro-nano vapor bubbles act as vaporization seeds to trigger nucleation boiling heat transfer in the evaporative radiator. The vapor-liquid mixture flowing out of the evaporator is fed into the vapor-liquid separator. The separated liquid is cooled by the cooler and returned to the liquid storage tank, while the separated vapor is condensed by the condenser and returned to the liquid storage tank.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects: A phase change cooling device for high heat flux density electronic components constructs a complete closed-loop phase change cooling circuit and places a cavitation device upstream of the evaporator radiator, ensuring that the coolant contains micro-nano vapor bubbles before entering the evaporator radiator. These bubbles, acting as vaporization seeds, reduce the uncertainty of nucleation boiling triggering after entering the heat exchange region, transforming boiling from dependence on random wall defects to dependence on actively supplied dynamic seeds. This improves the problems of random bubble nucleation, wall temperature fluctuations, and unstable two-phase flow. The vapor-liquid separator, cooler, and condenser form a separation and reflux path for liquid and gas, which helps maintain the stability of coolant circulation and the balance of system pressure and temperature.

[0018] Furthermore, the cavitation device is limited to any one or a combination of a venturi tube, a swirling device, a throttling orifice plate, a heating screen, or an ultrasonic device, providing multiple structural paths that can achieve cavitation. This overarching limitation retains the core technological concept of cavitation generating vaporized seed crystals while covering different implementation methods such as hydraulic cavitation, swirling cavitation, throttling cavitation, thermally induced bubbles, and ultrasonic cavitation, improving the adaptability of the scheme to different flow rates, pressures, heat loads, and spatial arrangement conditions.

[0019] Furthermore, the contraction section and throat accelerate the coolant and generate a local low-pressure zone, promoting cavitation conditions. The expansion section restores pressure and provides space for bubble growth and breakup. The swirling structure forms a swirling shear field within the expansion section, which enhances cavitation intensity and breaks larger bubbles into micro- and nano-sized vapor bubbles more suitable for downstream transport. This improves the continuity and dispersion of vaporized seed crystal formation.

[0020] Furthermore, when using a Venturi-cyclone device, a portion of the gas separated by the vapor-liquid separator is redirected back to the gas inlet of the Venturi device, providing additional vapor replenishment to the Venturi throat or low-pressure zone, thereby enhancing cavitation conditions. A gas flow meter is used to monitor the amount of redirected gas, and a check valve is used to prevent liquid backflow, improving the controllability and safety of branch line operation.

[0021] Furthermore, the orifice plate locally constricts the flow through the orifice, increasing the coolant velocity and decreasing the pressure, thereby inducing cavitation. The heating screen, located downstream, further promotes bubble formation and maintenance after the throttling cavitation. Combining throttling-induced cavitation with localized heat-promoted vaporization is suitable for cooling systems where it is inconvenient to install venturi tubes or where a compact cavitation module is required.

[0022] Furthermore, by utilizing some of the waste heat from the electronic components to thermally excite the heating screen, the coolant flowing near the screen is more likely to form or maintain bubbles. This design couples the waste heat from the electronic components with the vaporization seed formation process, which not only helps improve the bubble formation efficiency but also recovers local heat to a certain extent, enhancing the correlation between cavitation seed supply and heat load.

[0023] Furthermore, the Venturi tube provides the hydraulic cavitation conditions, while the ultrasonic vibration device provides the acoustic cavitation disturbance. The coupling of these two elements can create stronger pressure pulsations and localized cavitation regions in the coolant. This increases the quantity and persistence of micro / nano vapor bubbles, making it particularly suitable for applications where the intensity of single hydraulic cavitation is insufficient or the system flow rate is limited.

[0024] Furthermore, a parallel rectangular microchannel array is configured inside the evaporative heat exchanger, with the walls positively charged. The parallel rectangular microchannel array increases the heat transfer area, shortens the heat diffusion path, and ensures uniform distribution of the coolant containing vaporized seed crystals within the heat transfer region. The positively charged walls enhance the adsorption or enrichment of micro / nano vapor bubbles, making it easier for vaporized seed crystals to remain near the heated wall surface. This configuration improves the local nucleation boiling triggering capability and heat transfer uniformity.

[0025] Furthermore, temperature sensors are used to monitor the inlet and / or outlet temperatures of the evaporator radiator, and liquid flow meters are used to monitor the flow rate of coolant entering the cavitation unit. The computer adjusts the water pump and / or bypass diverter based on the temperature and flow signals, thereby regulating the flow rate and pressure entering the cavitation unit. The purpose is to enable the cavitation intensity to be adjusted according to changes in the heat load of electronic components, avoiding heat transfer instability caused by insufficient or excessive vaporization.

[0026] A phase change cooling method for high heat flux density electronic components transforms the passive and random bubble nucleation process in traditional phase change cooling into an active process of generating micro-nano vapor bubbles and transporting them to an evaporative radiator. This ensures a relatively stable supply of vaporization nuclei for the cooling system during startup, steady-state operation, and periods of fluctuating heat load. Vapor-liquid separation, cooling, and condensation reflux steps guarantee a closed-loop circulation of the cooling medium, improving the system's continuous operation capability.

[0027] In summary, this invention actively generates micro-nano vapor bubbles through a cavitation device and introduces them as dynamic vaporization seeds into an evaporative radiator, transforming phase change cooling from random nucleation to active and controllable nucleation. Combined with vapor-liquid separation, cooling condensation reflux, and flow rate and temperature regulation, it can reduce the instability of two-phase flow and improve the uniformity, reliability, and continuous operation capability of heat dissipation for high heat flux density electronic components.

[0028] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the following description of the relative embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the structure of the Chinese Churi-Swirl device of the present invention; Figure 3 This is a schematic diagram of the throttling orifice plate in this invention; Figure 4 This is a schematic diagram of the heated screen in this invention; Figure 5 This is a schematic diagram of the Chinese Churi-ultrasonic coupling cavitation device of the present invention.

[0031] The components include: 1. Liquid storage tank; 2. Water pump; 3. Liquid flow meter; 4. Computer; 5. Cavitation device; 6. Temperature sensor; 7. Evaporator radiator; 8. Cooler; 9. Condenser; 10. Vapor-liquid separator; 11. Gas flow meter; 12. Liquid inlet; 13. Contraction section; 14. Gas inlet; 15. Throat; 16. Swirl structure; 17. Expansion section; 18. Liquid outlet; 19. Orifice plate; 20. Heating screen; 21. Venturi tube; 22. Ultrasonic vibration device. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "one side," "one end," and "one side," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0035] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0036] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0037] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0038] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0039] This invention provides a phase change cooling device and method for high heat flux density electronic components, changing the bubble nucleation method in phase change cooling from passive random nucleation to active supply of vaporization seed crystals. Existing phase change cooling typically relies on wall defects, micro / nano structures, or localized overheating to generate bubbles, resulting in uncontrollable nucleation locations and frequencies, easily causing wall temperature fluctuations and unstable two-phase flow. This invention sets up a cavitation device upstream of the evaporator radiator, using methods such as Venturi flow, swirl flow, throttling, heated screens, or ultrasound to pre-generate micro / nano vapor bubbles in the coolant, which then serve as vaporization seed crystals entering the evaporator radiator with the coolant. This reduces the uncertainty of nucleation boiling triggering and improves the predictability and repeatability of boiling initiation. Furthermore, this invention uses vapor bubbles as dynamic seed crystals, rather than solid nanoparticles or fixed microstructures, avoiding problems such as particle agglomeration, deposition blockage, and microstructure failure due to high flow rates, making it suitable for long-term closed-loop operation. Furthermore, this invention establishes a stable cycle through vapor-liquid separation, liquid cooling reflux, and gas condensation reflux. Combined with temperature and flow rate monitoring to adjust pump power and bypass flow, the cavitation intensity can be adjusted according to changes in heat load. Therefore, this invention can improve the heat transfer efficiency, flow stability, and operational reliability of high heat flux density electronic components.

[0040] Example 1: Overall Phase Change Cooling Device Please see Figure 1 This embodiment provides a phase change cooling device for high heat flux density electronic components. The device includes a liquid storage tank 1, a water pump 2, a liquid flow meter 3, a computer 4, a cavitation device 5, a temperature sensor 6, an evaporative radiator 7, a cooler 8, a condenser 9, a vapor-liquid separator 10, and a gas flow meter 11.

[0041] The coolant reservoir 1 is used to store coolant. An inlet is located at the top of the reservoir 1 to receive returning coolant; an outlet is located at the bottom of the reservoir 1, and a removable filter assembly is installed at the outlet. The outlet of the reservoir 1 is connected to the liquid inlet of the water pump 2 via a pressure-resistant pipe. The water pump 2 is used to transport the coolant from the reservoir 1 to the subsequent circulation pipeline.

[0042] The liquid flow meter 3 includes a liquid inlet, a liquid outlet, and a signal output interface. The liquid inlet of the liquid flow meter 3 is connected to the diversion device after the liquid outlet of the water pump 2, the liquid outlet of the liquid flow meter 3 is connected to the liquid inlet of the cavitation device 5, and the signal output interface of the liquid flow meter 3 is connected to the computer 4 to detect the flow rate of the coolant entering the cavitation device 5 and transmit the flow signal to the computer 4.

[0043] A cavitation device 5 is installed between the liquid flow meter 3 and the evaporator 7 to cause cavitation of the coolant flowing through it and generate micro-nano vapor bubbles. The generated micro-nano vapor bubbles act as vaporization seeds and enter the evaporator 7 with the coolant, triggering nucleation boiling heat transfer within the evaporator 7 when electronic components generate heat.

[0044] The evaporative heat sink 7 is used for thermal connection with high heat flux density electronic components. The evaporative heat sink 7 has an internal array of parallel rectangular microchannels serving as a phase change heat transfer area. The evaporative heat sink 7 can be made of copper to improve heat transfer efficiency. The evaporative heat sink 7 can be sealed to the electronic components using adhesive bonding, screws with gaskets, crystal bonding, or soldering.

[0045] Temperature sensor 6 includes a detection device and a signal output interface. Temperature sensor 6 is installed at the inlet and outlet of evaporator 7 to detect temperature changes of the coolant at the inlet and outlet of evaporator 7. The signal output interface of temperature sensor 6 is connected to computer 4 so that computer 4 can acquire temperature signals in real time.

[0046] A vapor-liquid separator 10 is located at the outlet side of the evaporator radiator 7 to receive the vapor-liquid mixture flowing out of the evaporator radiator 7 and separate the vapor and liquid. The vapor-liquid separator 10 is a vertical cylindrical cyclone devastater, including a liquid inlet, a vapor outlet, and a liquid outlet. The vapor-liquid separator 10 also includes a cylindrical section, a conical separation section, and a vapor collection chamber. After the vapor-liquid mixture enters the vapor-liquid separator 10 through the tangential liquid inlet, a high-rotation flow field is formed within the conical separation section. The vapor rises along the central region to the top vapor outlet, while the devastated liquid is discharged from the bottom liquid outlet.

[0047] Cooler 8 is connected between the liquid outlet at the bottom of vapor-liquid separator 10 and liquid storage tank 1, and is used to cool the liquid after vapor-liquid separation and return it to liquid storage tank 1. Condenser 9 is connected between the gas outlet at the top of vapor-liquid separator 10 and liquid storage tank 1, and is used to condense and liquefy the vapor after vapor-liquid separation and return it to liquid storage tank 1, thereby forming a closed cooling cycle and maintaining the stability of system pressure and circulation temperature.

[0048] The gas flow meter 11 includes a gas inlet, a gas outlet, and a signal output interface. When the cavitation device 5 includes a venturi tube, the gas inlet of the gas flow meter 11 is connected to the gas-liquid separator 10, the gas outlet of the gas flow meter 11 is connected to the gas inlet of the venturi tube, and the signal output interface of the gas flow meter 11 is connected to the computer 4. A check valve is installed at the outlet of the gas flow meter 11 to prevent liquid backflow.

[0049] The water pump 2, liquid flow meter 3, cavitation device 5 and evaporator 7 are connected by pressure-resistant stainless steel pipe or polytetrafluoroethylene hose, and the interface adopts flange or threaded connection to ensure the system's sealing and corrosion resistance.

[0050] Computer 4 is connected to liquid flow meter 3, gas flow meter 11, and temperature sensor 6 via data cable or wireless communication module to receive temperature signals, liquid flow signals, and gas flow signals, enabling real-time data acquisition, control, and recording. A bypass diversion device is installed between the outlet of water pump 2 and the liquid flow meter 3, allowing the portion of liquid not participating in the phase change cooling cycle to return to the storage tank 1 via the bypass. Computer 4 can adjust the pump power of water pump 2 and the bypass diversion device based on the temperature and flow signals from evaporator radiator 7 to regulate the liquid flow rate and pressure entering cavitation device 5, thereby changing the cavitation intensity.

[0051] Furthermore, the wall surface of the evaporative radiator 7 can be positively charged by applying a low voltage of no more than 5V, and the electrostatic attraction intensity can be controlled by adjusting the voltage to attract micro-nano vapor bubbles, making it easier for micro-nano vapor bubbles to accumulate near the heat exchange wall surface.

[0052] Example 2: Venturi-Swirl Cavitation Device Please see Figure 2 In one alternative embodiment, the cavitation device 5 is a Venturi vortex device. The Venturi vortex device includes a liquid inlet 12, a contraction section 13, a gas inlet 14, a throat 15, a vortex structure 16, an expansion section 17, and a liquid outlet 18.

[0053] After the coolant enters the Venturi vortex apparatus through the liquid inlet 12, it is first accelerated through the contraction section 13, and a local low-pressure zone is formed at the throat 15, thereby promoting cavitation of the coolant. The contraction section 13 of the Venturi vortex apparatus has an angle of 10° to 30° with the central axis, which is used to provide effective acceleration and pressure drop for the liquid flow, so that it reaches the conditions required for cavitation. The expansion section 17 has an angle of 5° to 25° with the central axis, which is used to smoothly restore the fluid pressure and provide space for the subsequent growth and breakup of bubbles.

[0054] The swirling structure 16 is located in the middle and rear part of the expansion section 17 to generate a swirling flow field, reduce the pressure in the central region, thereby promoting cavitation initiation and enhancing cavitation intensity. At the same time, the swirling structure 16 can form a swirling shear field in the high-velocity region of the axis, breaking cavitation bubbles into nanoscale vapor bubbles, improving the dispersion and in-flow transport capacity of vaporized seeds.

[0055] When the cavitation device 5 includes a Venturi tube, a portion of the steam separated by the vapor-liquid separator 10 can flow through the gas flow meter 11 and then enter the Venturi-cyclone device through the gas inlet 14 to enhance the cavitation effect and promote the stable generation of micro-nano vapor bubbles. A check valve is installed in the gas return branch to prevent liquid backflow.

[0056] Example 3: Throttling-Heating Screen Cavitation Device Please see Figure 3 and Figure 4 In another alternative embodiment, the cavitation device 5 is a throttling-heating screen device. This throttling-heating screen device includes a throttling orifice plate 19 and a heating screen 20.

[0057] The orifice plate 19 has 10 to 20 circular orifices, which are evenly arranged in a circle. When the coolant flows through the orifice plate 19, the flow velocity increases sharply and a low-pressure zone is formed downstream of the orifice plate. When the pressure is lower than the saturated vapor pressure of the coolant, cavitation is induced and nanoscale vapor bubbles are generated.

[0058] A heating screen 20 is located downstream of the orifice plate 19. The heating screen 20 is made of copper and features a uniformly distributed diamond-shaped mesh. The heating screen 20 contacts the electronic components via a heat-conducting substrate, allowing some of the waste heat from the electronic components to be transferred to the heating screen 20, further promoting bubble generation while utilizing the waste heat. The heating screen 20 and the orifice plate 19 can be connected via snap-fit ​​with a sealing gasket or by adhesive.

[0059] By generating local throttling, speed increase and pressure drop through the throttling orifice plate 19, and combined with the local thermal effect of the heating screen 20, this embodiment can form and maintain micro-nano vapor bubbles in the coolant, allowing them to enter the evaporator radiator 7 as vaporization seeds.

[0060] Example 4: Venturi-Ultrasonic Coupling Cavitation Device Please see Figure 5 In another alternative embodiment, the cavitation device 5 is a Venturi-ultrasonic coupled cavitation device. This Venturi-ultrasonic coupled cavitation device includes a Venturi tube 21 and an ultrasonic vibration device 22.

[0061] The Venturi tube 21 is used to generate hydraulic cavitation through fluid acceleration and local pressure drop; the ultrasonic vibration device 22 is installed on the Venturi tube 21 to apply ultrasonic vibration to the coolant flowing through the Venturi tube 21, so that ultrasonic cavitation and Venturi hydraulic cavitation occur simultaneously. The interaction between the two helps to improve the cavitation effect and continuously obtain micro-nano vapor bubbles.

[0062] The venturi tube 21 and the ultrasonic vibration device 22 can be connected by welding or adhesive bonding. This coupled cavitation method is suitable for applications requiring enhanced cavitation intensity or for continuous acquisition of micro-nano steam bubbles when the effect of single hydraulic cavitation is insufficient.

[0063] Example 5: Phase Change Cooling Method Please see Figures 1 to 5 This embodiment provides a phase change cooling method for high heat flux density electronic components, employing the aforementioned phase change cooling device, and includes the following steps: S1, Coolant delivery and flow regulation Coolant is injected into the storage tank 1, and then pumped by the water pump 2 to the liquid flow meter 3. The pump power of the water pump 2 and the bypass valve are adjusted according to the set parameters to ensure stable liquid flow rate and pressure entering the cavitation device 5. The liquid flow meter 3 monitors the flow signal in real time and transmits the flow data to the computer 4 for controlling and recording system operating parameters.

[0064] S2, cavitation generates vaporized seed crystals After the coolant enters the cavitation device 5, cavitation occurs under the action of any one or a combination of a venturi tube, a vortex device, a throttling orifice plate, a heating screen, or an ultrasonic device, continuously generating micro-nano-sized vapor bubbles. These micro-nano-sized vapor bubbles serve as vaporization seeds and continue to flow with the coolant to the evaporator radiator 7.

[0065] S3, Evaporative Radiator Core State Boiling Heat Transfer Coolant containing micro-nano vapor bubbles flows into evaporative radiator 7. When electronic components generate heat, the micro-nano vapor bubbles act as vaporization nuclei, triggering stable and controllable nucleation boiling, thereby enhancing the heat transfer process. Temperature sensors 6 are installed at the inlet and outlet of evaporative radiator 7 to monitor coolant temperature changes in real time and transmit the temperature signals to computer 4 for controlling, recording, and adjusting system operating parameters. S4, vapor-liquid separation.

[0066] The vapor-liquid mixture flows out of the outlet of the evaporator radiator 7 and enters the vapor-liquid separator 10, where the liquid and gas are separated under the strong centrifugal field inside the cyclone devastater. The separated liquid is sent to the cooler 8 through the liquid outlet at the bottom of the vapor-liquid separator 10, and the separated gas is sent to the condenser 9 through the gas outlet at the top of the vapor-liquid separator 10. Venturi-enhanced cavitation When the cavitation device 5 includes a venturi tube, a portion of the steam separated by the vapor-liquid separator 10 enters the venturi tube through the gas inlet to enhance the cavitation effect and promote the stable generation of micro-nano vapor bubbles. The flow rate of this portion of steam can be detected by the gas flow meter 11, and the check valve in the gas return branch is used to prevent liquid backflow.

[0067] S5, Cooling and Condensation Reflux After separation, the liquid is cooled in cooler 8 and then returned to storage tank 1; after separation, the gas is condensed and liquefied in condenser 9 and then returned to storage tank 1, completing the closed-loop circulation of coolant.

[0068] Through the above embodiments, this application utilizes the cavitation device 5 to actively and continuously generate micro-nano vapor bubbles, which are then introduced into the evaporator radiator 7 as dynamic vaporization seeds. This transforms the phase change cooling process of high heat flux density electronic components from random natural nucleation to a nucleation boiling process actively supplied with vaporization seeds. Compared to schemes that rely on static micro-nano structures or solid particles as vaporization nuclei, this application can reduce the risk of static structure erosion failure and solid particle agglomeration and deposition. Furthermore, it achieves cavitation intensity control under different heat loads through temperature and flow monitoring, as well as pump power and bypass adjustment.

[0069] In summary, this invention provides a phase change cooling device and method for high heat flux density electronic components. By installing a cavitation device at the front end of an evaporative heat exchanger, and utilizing cavitation methods such as Venturi, swirl, throttling, heating screens, or ultrasound, micro- and nano-sized vapor bubbles are actively and continuously generated before the coolant enters the heat exchange zone. These bubbles act as dynamic vaporization seeds, entering the evaporative heat exchanger with the fluid. Therefore, the phase change cooling process no longer relies primarily on heating wall defects, local overheating, or random natural nucleation. Instead, it provides stable vaporization nuclei through an externally adjustable cavitation mechanism, making nucleated boiling easier to trigger and the boiling initiation point more predictable and repeatable. This reduces wall temperature fluctuations and vapor-liquid two-phase flow instability, improving the heat dissipation reliability of high heat flux density electronic components.

[0070] Meanwhile, the present invention uses micro-nano vapor bubbles as vaporization seed crystals, which, compared with the solution of adding solid nanoparticles, will not introduce long-term operation risks such as particle agglomeration, deposition, wear or blockage of microchannels; compared with the solution of processing porous coatings, micro-pillar arrays and other static microstructures on the wall surface, micro-nano bubbles can be continuously replenished with coolant, are not easy to fail due to high flow rate scouring, and have better cycle adaptability and maintenance convenience.

[0071] Furthermore, this invention, through temperature monitoring, flow rate monitoring, pump power adjustment, and bypass diversion regulation, enables the flow rate and pressure entering the cavitation device to be adjusted according to changes in the heat load of electronic components. This alters the cavitation intensity and the supply of vaporized seed crystals, achieving stable heat transfer from low load to high heat flux density conditions. Overall, this invention combines the advantages of active nucleation, anti-deposition, controllability, and closed-loop operation, thereby improving the heat transfer efficiency, operational stability, and engineering reliability of phase change cooling systems.

[0072] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A phase change cooling device for high heat flux density electronic components, characterized in that, The system includes a storage tank (1), a water pump (2), a liquid flow meter (3), a cavitation device (5), an evaporative radiator (7), and a vapor-liquid separator (10) connected sequentially along the coolant circulation direction. The liquid outlet of the vapor-liquid separator (10) is connected to the storage tank (1) via a cooler (8), and the gas outlet of the vapor-liquid separator (10) is connected to the storage tank (1) via a condenser (9). The cavitation device (5) is used to cavitate the coolant and generate micro-nano vapor bubbles. The micro-nano vapor bubbles serve as vaporization seeds and enter the evaporative radiator (7) with the coolant. The evaporative radiator (7) is used for thermal connection with high heat flux density electronic components so that the coolant containing the vaporization seeds undergoes nucleation boiling heat exchange within the evaporative radiator (7).

2. The phase change cooling device for high heat flux density electronic components according to claim 1, characterized in that, The cavitation device (5) includes any one or a combination of at least two of the following: a venturi tube, a cyclone device, a throttling orifice plate, a heating screen, or an ultrasonic device.

3. The phase change cooling device for high heat flux density electronic components according to claim 2, characterized in that, The cavitation device (5) is a Venturi vortex device, which includes a liquid inlet (12), a contraction section (13), a throat (15), an expansion section (17), and a liquid outlet (18) connected in sequence. A vortex structure (16) is provided in the expansion section (17).

4. The phase change cooling device for high heat flux density electronic components according to claim 3, characterized in that, The Venturi-cyclone device also includes a gas inlet (14). One end of the gas return branch is connected between the gas outlet of the gas-liquid separator (10) and the condenser (9), and the other end is connected to the gas inlet (14). A gas flow meter (11) and a check valve are provided on the gas return branch.

5. The phase change cooling device for high heat flux density electronic components according to claim 2, characterized in that, The cavitation device (5) is a throttling-heating screen device, which includes a throttling orifice plate (19) and a heating screen (20). The throttling orifice plate (19) is provided with a plurality of throttling orifices, and the heating screen (20) is located on the downstream side of the throttling orifice plate (19).

6. The phase change cooling device for high heat flux density electronic components according to claim 5, characterized in that, The heating screen (20) is thermally connected to the high heat flux density electronic components through a thermally conductive substrate.

7. The phase change cooling device for high heat flux density electronic components according to claim 2, characterized in that, The cavitation device (5) is a Venturi-ultrasonic coupled cavitation device, which includes a Venturi tube (21) and an ultrasonic vibration device (22) disposed on the Venturi tube (21).

8. The phase change cooling device for high heat flux density electronic components according to claim 1, characterized in that, The evaporative radiator (7) has a parallel rectangular microchannel array inside, and the wall of the evaporative radiator (7) is connected to a low voltage power supply of no more than 5V so that the wall is positively charged.

9. The phase change cooling device for high heat flux density electronic components according to claim 1, characterized in that, It also includes a temperature sensor (6) and a computer (4). The temperature sensor (6) is respectively located at the inlet and outlet of the evaporator (7). The computer (4) is respectively connected to the liquid flow meter (3) and the temperature sensor (6). A bypass diversion device connected to the liquid storage tank (1) is provided on the outlet side of the water pump (2). The computer (4) is used to adjust the water pump (2) and / or the bypass diversion device according to the detection signals of the liquid flow meter (3) and the temperature sensor (6).

10. A phase change cooling method for high heat flux density electronic components, characterized in that, The high heat flux density electronic component phase change cooling device according to any one of claims 1 to 9 includes the following steps: The coolant in the storage tank (1) is pumped to the cavitation device (5) by the water pump (2); The cavitation device (5) causes the coolant to cavitate and generate micro-nano vapor bubbles; The coolant containing the micro-nano vapor bubbles is transported to the evaporator (7), so that the micro-nano vapor bubbles act as vaporization seeds to trigger nucleation boiling heat transfer in the evaporator (7). The vapor-liquid mixture flowing out of the evaporator (7) is fed into the vapor-liquid separator (10). The separated liquid is cooled by the cooler (8) and returned to the liquid storage tank (1). The separated gas is condensed by the condenser (9) and returned to the liquid storage tank (1).

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