cooling device

Abstract

The application provides a cooling device for cooling a heat-generating body in a cooling pool, which comprises a heat exchange base capable of being wrapped around the heat-generating body, a cooling structure arranged on the heat exchange base, and a liquid supplementing part arranged on the cooling structure and away from the heat exchange base; the heat exchange base, the cooling structure and the liquid supplementing part form a channel, the channel has a first end and a second end, and the cross-sectional area of the channel gradually increases from the first end to the second end along the extension direction of the channel; the bubbles can be discharged out of the channel from the second end under the guidance of the side wall of the channel, and the cooling medium in the cooling pool can supplement liquid into the channel through the liquid supplementing part. The application effectively delays the situation that a large number of bubbles gather to form a gas film covering the surface of the heat-generating body to hinder the re-wetting of the cooling working medium to the surface of the heat-generating body, so that the heat transfer performance is sharply deteriorated, and the cooling efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heat transfer enhancement, in particular to a cooling device. BACKGROUND

[0002] With the rapid development of modern technologies such as high-performance computing, high-frequency communication equipment, and artificial intelligence, the requirements for chip integration and miniaturization are continuously increasing, leading to a continuous rise in chip power density, which in turn brings about tremendous thermal management challenges. High power density can cause significant temperature rise, which in turn affects the reliability and lifespan of the chip. Therefore, efficient heat dissipation technology has become the key to ensuring the safe and stable operation of the chip.

[0003] In related technologies, the research focus of cooling technology for heat-generating bodies such as electronic chips includes indirect cold plates and immersion cooling technology, which is further divided into single-phase cooling and phase change cooling. Compared with single-phase cooling, phase change cooling has better heat exchange efficiency and unique advantages in maintaining temperature uniformity. However, under high heat flux density conditions, bubbles are easily aggregated and form a gas film covering the surface of the heat-generating body. This hinders the re-wetting of the cooling medium to the surface of the heat-generating body, thereby causing a sharp deterioration in heat transfer performance. SUMMARY

[0004] In view of the above, the present application aims to provide a cooling device to help improve cooling efficiency.

[0005] To achieve the above-mentioned purposes, the technical solution of the present application is as follows:

[0006] A cooling device for cooling a heat-generating body in a cooling pool, the cooling device comprising:

[0007] a heat exchange base capable of being wrapped around the heat-generating body, a cooling structure arranged on the heat exchange base, and a liquid supplementing portion arranged on the cooling structure and facing away from the heat exchange base;

[0008] The heat exchange base, the cooling structure, and the liquid supplementing portion form a channel, the channel having a first end and a second end, and the cross-sectional area of the channel gradually increases from the first end to the second end along the extension direction of the channel;

[0009] The bubbles can be discharged out of the channel from the second end under the guidance of the side wall of the channel, and the cooling medium in the cooling pool can supplement liquid into the channel through the liquid supplementing portion.

[0010] Further, the cooling structure comprises a plurality of guide plates arranged in a predetermined direction, and the adjacent two guide plates, the heat exchange base, and the liquid supplementing portion form the channel.

[0011] Further, the cooling structure further comprises a base column arranged on the heat exchange substrate; the preset direction is the circumferential direction of the base column; a plurality of the guide plates are distributed along the circumferential direction of the base column; one end of the guide plate is connected with the base column, and the other end of the guide plate extends to the edge of the heat exchange substrate along the radial direction of the base column.

[0012] Further, the included angle between two adjacent guide plates ranges from 5° to 30°, and / or, the two adjacent guide plates are distributed at equal angles.

[0013] Further, the preset direction is the length or width direction of the heat exchange substrate; the guide plate is in a strip shape, and the cross-sectional area of the guide plate gradually decreases from the center of the guide plate to both ends of the guide plate in the length direction of the guide plate; the first end is located at the center of the length direction of the guide plate, and the second end is located at both ends of the length direction of the guide plate.

[0014] Further, the preset direction is the length or width direction of the heat exchange substrate, and two adjacent guide plates form a group; one end of the two guide plates in the same group is close to each other to form the first end, and the other end is away from each other to form the second end; the first end and the second end of the two adjacent channels are alternately arranged along the preset direction.

[0015] Further, the cooling structure is coated with a temperature-sensitive wetting coating; the components of the temperature-sensitive wetting coating include 1H, 1H, 2H, 2H-perfluorodecyltrichlorosilane and TiO2.

[0016] Further, the surface of the heat exchange substrate has hydrophilicity.

[0017] Further, the surface of the heat exchange substrate provided with the cooling structure is in a rectangular or circular shape; the base column is located at the center of the heat exchange substrate, and the end of the guide plate away from the base column extends to the edge of the heat exchange substrate.

[0018] Further, the liquid supplementing part comprises a liquid supplementing plate arranged on the cooling structure, the liquid supplementing plate is made of one or more of foamed metal, expanded polytetrafluoroethylene, polyimide aerogel and porous polyether ether ketone, and / or,

[0019] The cooling structure (2) is made of one of copper, silicon, aluminum, polytetrafluoroethylene, polyimide, polyether ether ketone, zirconium tungstate, invar, scandium fluoride, nickel-titanium alloy, copper-zinc-aluminum alloy.

[0020] Compared with the prior art, the present application has the following advantages:

[0021] The cooling device provided by the application, by setting the channel, as the bubbles form and grow in the channel, the bubbles present a shape with a small head and a large tail under the restriction and guidance of the channel side wall, that is, the bubbles gradually present an expanding state from the side close to the first end to the side close to the second end, and the bubbles with the above-mentioned shape move in the expanding direction under the action of surface tension, thereby promoting the bubbles to separate from the channel at the second end under the guidance of the channel side wall.

[0022] At the same time, in the channel, the more the bubbles generated, the more the steam amount, and the more the steam amount, the greater the channel resistance, and the more the bubbles generated, the smaller the channel pressure; and in the liquid supplementing part, the flow rate of the cooling working medium is low, and the pressure gradient is relatively small, the cooling working medium is transported into the channel with high resistance, that is, small pressure, to realize the liquid supplementing of the cooling working medium in the channel. Further delay the situation that a large number of bubbles gather to form a gas film covering the surface of the heat generating body to hinder the re-wetting of the cooling working medium to the surface of the heat generating body, so as to make the heat transfer performance deteriorate sharply, and improve the cooling efficiency.

[0023] And, under the same inlet pressure, the more the bubbles generated in the channel, the lower the pressure of the channel, and the liquid supplementing of the channel is relatively more timely, thereby realizing the targeted cooling working medium supplementing of the different channels corresponding to different positions of the heat exchange base, and the cooling of the heat exchange base is more uniform.

[0024] Secondly, by setting the angle range of the included angle between the two adjacent guide plates to be 5°-30°, it is convenient for the bubbles to form a shape with a small head and a large tail as the bubbles grow in the channel, that is, it is convenient for the bubbles to present an expanding state in the channel. At the same time, effectively avoid the situation that the bubbles tend to be long strip-shaped and the expanding state in the channel is not obvious, so that the bubbles cannot be discharged to the outside of the channel in the expanding direction under the action of surface tension due to the too small angle between the two adjacent guide plates. And effectively avoid the situation that the bubbles cannot be restricted and guided due to the too large angle between the two adjacent guide plates, so that there is no extrusion force from the channel on both sides of the bubbles, leading to the bubbles tending to be spherical, and the expanding state in the channel is not obvious, so that the bubbles cannot be discharged to the outside of the channel in the expanding direction under the action of surface tension.

[0025] Furthermore, by applying a temperature-sensitive wetting coating, and considering that the wettability requirement of bubbles dynamically changes at different stages from bubble formation to detachment, hydrophobic cooling structures are more conducive to nucleation and can effectively reduce nucleation superheat, while hydrophilic surfaces can reduce the bubble base radius, accelerate the contraction of the triple phase lines, and facilitate bubble detachment. Macroscopically, hydrophobic surfaces have a lower initial nucleation temperature (ONB), thus their boiling heat transfer coefficient (HTC) is higher in the early stages than that of hydrophilic surfaces. However, bubbles detach more easily on hydrophilic surfaces, and liquid replenishment is also faster, resulting in a higher boiling heat transfer coefficient and a higher critical heat flux (CHF) on hydrophilic surfaces in the later stages. In summary, applying a temperature-sensitive wetting coating facilitates bubble generation and detachment, contributing to further improvements in cooling efficiency. Attached Figure Description

[0026] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0027] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram showing the arrangement of the heat exchange substrate, cooling structure, and liquid replenishment section according to an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the cooling structure described in an embodiment of the present invention;

[0030] Figure 4 This is a schematic diagram of the cooling structure of the present invention coated with a temperature-sensitive wetting coating.

[0031] Figure 5 This is a schematic diagram showing the arrangement of the heat exchange substrate, cooling structure, and liquid replenishment section according to an embodiment of the present invention;

[0032] Figure 6 This is a schematic diagram of the cooling structure described in an embodiment of the present invention;

[0033] Figure 7 This is a schematic diagram showing the arrangement of the heat exchange substrate, cooling structure, and liquid replenishment section according to an embodiment of the present invention;

[0034] Figure 8 This is a schematic diagram of the cooling structure described in an embodiment of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Heat exchange substrate; 2. Cooling structure; 201. Guide plate; 202. Base column; 3. Liquid replenishment section; 31. Liquid replenishment plate; 4. Channel; 4a. First end; 4b. Second end; 5. Temperature-sensitive wettable coating; 6. Cooling pool; 7. Heating element; 8. Bubble; α. Angle; β. Preset direction; γ. Expansion direction. Detailed Implementation

[0037] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0038] In the description of this invention, it should be noted that the use of terms such as "upper," "lower," "inner," and "outer," indicating orientation or positional relationship, is based on the orientation or positional relationship shown in the accompanying drawings and is only for the convenience of describing the invention and simplifying the description. It does 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 use of terms such as "first" and "second" is also for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] Furthermore, in the description of this invention, unless otherwise explicitly defined, the terms "installation," "connection," "joining," and "connector" 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 in light of the specific circumstances.

[0040] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] This embodiment relates to a cooling device that uses a spatial structure to achieve self-driven boiling bubbles and directional liquid replenishment, thereby helping to improve cooling efficiency.

[0042] Current research hotspots in cooling technologies for heat-generating components 7, such as electronic chips, include indirect cooling plates and immersion cooling technologies. Immersion cooling is further divided into single-phase cooling and phase change cooling. Compared with single-phase cooling, phase change cooling has better heat transfer efficiency and unique advantages in maintaining temperature uniformity. However, under high heat flux density conditions, the bubbles 8 generated during phase change cooling tend to aggregate and form a gas film that covers the surface of the heat-generating component 7. This hinders the rewetting of the heat-generating component 7 by the cooling medium, thus drastically deteriorating the heat transfer performance.

[0043] Example 1

[0044] In terms of overall structure, such as Figures 1 to 3As shown, the cooling device is used to cool the heating element 7 in the cooling pool 6. The cooling device includes a heat exchange substrate 1 that can cover the heating element 7, a cooling structure 2 disposed on the heat exchange substrate 1, and a liquid replenishment section 3 disposed on the cooling structure 2 and facing away from the heat exchange substrate 1. The heat exchange substrate 1, the cooling structure 2, and the liquid replenishment section 3 form a channel 4. The channel 4 has a first end 4a and a second end 4b. Along the extending direction of the channel 4, the cross-sectional area of ​​the channel 4 gradually increases from the first end 4a to the second end 4b. Guided by the sidewall of the channel 4, bubbles 8 can be discharged from the second end 4b to the outside of the channel 4. The cooling medium in the cooling pool 6 can be replenished into the channel 4 through the liquid replenishment section 3.

[0045] With the above settings, as bubbles 8 form and grow in channel 4, under the restriction and guidance of the sidewall of channel 4, bubbles 8 exhibit a shape with a small head and a large tail. That is, bubbles 8 gradually expand from the side near the first end 4a to the side near the second end 4b. As described above, bubbles 8 with the above shape will move in the expansion direction γ under the action of surface tension, thereby promoting bubbles 8 to detach from the second end 4b and exit channel 4 under the guidance of the sidewall of channel 4.

[0046] Meanwhile, within channel 4, the more bubbles 8 are generated, the more steam is produced. Channel 4 with more steam has greater resistance. Since flow resistance is proportional to pressure drop, channel 4 with more bubbles 8 has lower pressure. In the replenishment section 3, the cooling medium flow rate is lower, and the pressure gradient is relatively smaller. The cooling medium is transported to channel 4, which has higher resistance and lower pressure, thus replenishing the cooling medium within channel 4. This delays the formation of a gas film from a large number of bubbles 8 covering the surface of the heating element 7, preventing the rewetting of the heating element 7 surface by the cooling medium and thus drastically deteriorating heat transfer performance, thereby improving cooling efficiency. Furthermore, under the same inlet pressure, the channel 4 with more bubbles 8 has lower pressure, and replenishment of the cooling medium in this channel 4 is more timely. This allows for targeted replenishment of the cooling medium to different channels 4 corresponding to different locations on the heat exchange substrate 1, resulting in more uniform cooling of the heat exchange substrate 1. It is understandable that when the amount of bubble 8 generated is small, that is, when the heat flux density is small, channel 4 can still promote the expulsion of bubble 8. At the same time, the liquid replenishment section 3 can also replenish liquid into channel 4.

[0047] Based on the above overview, it is worth noting that, as Figure 1As shown, in this embodiment, the cooling pool 6 is filled with a cooling medium, and the heating element 7 and the cooling device are immersed in the cooling medium. Under boiling conditions, the phase change cooling technology mainly relies on the formation, growth, rapid detachment, and timely replenishment of the cooling medium after detachment of the bubbles 8. The heat generated by the heating element 7 is conducted to the cooling structure 2 by the heat exchange substrate 1. The temperature reaches the saturation temperature of the cooling medium, achieving a certain degree of superheat. The vaporization nuclei of the cooling medium in the channel 4 are activated first because their temperature reaches the activation temperature first, generating bubbles 8, which gradually grow. The increased volume of the bubbles 8 generates expansion force, and under the action of the sidewall of the channel 4, they are subjected to a reaction compressive force, causing the originally expanding bubbles 8 to accelerate towards the second end b. Specifically, the curvature of the same bubble 8 at the first end a is less than that at the second end b, so the surface tension of the bubble 8 at the first end a is smaller, and the force difference drives the bubble towards the second end b. Common cooling media can be selected, such as water, fluorinated liquid, methanol, ethanol, acetone, etc. In this embodiment, fluorinated liquid is preferably used as the cooling medium.

[0048] Based on the above introduction, in detail, as follows: Figure 3 As shown, the cooling structure 2 includes multiple guide plates 201 arranged along a preset direction β. Adjacent guide plates 201, the heat exchange substrate 1, and the liquid replenishment part 3 form a channel 4. In a specific implementation, this embodiment further includes a base column 202 disposed on the heat exchange substrate 1; the preset direction β is the circumferential direction of the base column 202, and the multiple guide plates 201 are distributed along the circumferential direction of the base column 202; one end of the guide plate 201 is connected to the base column 202, and the other end of the guide plate 201 extends radially towards the edge of the heat exchange substrate 1 along the base column 202.

[0049] With the above configuration, the guide plate 201 is centered on the base column 202 and distributed circumferentially along the base column 202, which facilitates the detachment of the bubble 8 from the channel 4 along the circumference of the heat exchange substrate 1, so as to achieve heat dissipation around the heat exchange substrate 1 and help to make the cooling of the heat exchange substrate 1 more uniform.

[0050] In a preferred embodiment of the cooling structure 2 described above, the surface of the heat exchange substrate 1 on which the cooling structure 2 is provided is preferably rectangular or circular; the base column 202 is located at the center of the heat exchange substrate 1. This arrangement helps to ensure that the lengths of the two channels 4, which are symmetrical about the center of the base column 202, are consistent, thereby helping to ensure that the growth and detachment times of the bubbles 8 are consistent. In another preferred embodiment of the cooling structure 2, one end of the guide plate 201 is fixedly connected to the base column 202, and the remaining end extends to the edge of the heat exchange substrate 1. The liquid replenishment part 3 can completely cover the contact surface of the guide plate 201. This arrangement helps to increase the area of ​​the channels 4 and the area for replenishing liquid into the channels 4, which helps to dissipate heat from the entire heat exchange substrate 1.

[0051] Meanwhile, as a preferred embodiment of the cooling structure 2 described above, specifically, in implementation, the included angle α between two adjacent guide plates 201 ranges from 5° to 30°. The two adjacent guide plates 201 are distributed at equal angles. For example, the included angle α can be 5°, 10°, 15°, 20°, 25°, or 27°, and preferably 15°.

[0052] The above configuration facilitates the formation of a small head and a large tail for bubbles 8 as they grow within channel 4, thus promoting an expanding state within the channel 4. Simultaneously, it effectively avoids the situation where an excessively small angle α between adjacent guide plates 201 causes bubbles 8 to become elongated, resulting in insignificant expansion within channel 4 and preventing them from being discharged out of channel 4 under the influence of surface tension along the expansion direction γ. It also effectively avoids the situation where an excessively large angle α between adjacent guide plates 201 fails to restrict and guide bubbles 8, causing them to become spherical due to lack of pressure from channel 4 on both sides, resulting in insignificant expansion within channel 4 and preventing them from being discharged out of channel 4 under the influence of surface tension along the expansion direction γ.

[0053] When the included angle α between two adjacent guide plates 201 is equal, it helps to make the two adjacent channels 4 tend to be the same size, that is, it helps to make the corresponding heat exchange substrate 1 area tend to be the same, thus making the cooling of the heat exchange substrate 1 more uniform.

[0054] Based on the above overall introduction, such as Figure 4 As shown, the cooling structure 2 is coated with a temperature-sensitive wetting coating 5; the components of the temperature-sensitive wetting coating 5 include 1H,1H,2H,2H-perfluorodecyltrichlorosilane and TiO2.

[0055] With the above settings, and considering that the wettability requirement of bubble 8 changes dynamically at different times from bubble formation to detachment, the hydrophobic cooling structure 2 is more conducive to nucleation and can effectively reduce nucleation superheat, while the hydrophilic surface can reduce the base radius of bubble 8, accelerate the contraction of the three-phase line, and facilitate the detachment of bubble 8. Macroscopically, the hydrophobic surface has a lower initial nucleation temperature (ONB), so its boiling heat transfer coefficient (HTC) is higher in the early stage than that of the hydrophilic surface. The hydrophobic surface cannot restrict or guide bubble 8, resulting in no extrusion pressure from channel 4 on both sides of bubble 8, causing bubble 8 to tend towards a spherical surface. However, bubble 8 is easier to detach on the hydrophilic surface, and liquid replenishment is also faster. Therefore, the boiling heat transfer coefficient of the hydrophilic surface is higher in the later stage, and it also has a higher critical heat flux density (CHF). In summary, setting the temperature-sensitive wettability coating 5 helps the generation and detachment of bubble 8, and helps to further improve cooling efficiency.

[0056] As an optional embodiment of the temperature-sensitive wetting coating 5, specifically, as an optional embodiment of the production and coating of the temperature-sensitive wetting coating 5, for example, 0.2 g of TiO2 is added to 100 ml of anhydrous ethanol, ultrasonically dispersed for 30 minutes, and then 1 ml of 1H,1H,2H,2H-perfluorodecyltrichlorosilane is added, and magnetic stirring is continued for 30 minutes to obtain the temperature-sensitive wetting coating 5 spray. The spray is then applied to the cooling structure 2 using a spray gun, and subsequently dried at 60°C for 1 hour to form the temperature-sensitive wetting coating 5 with temperature-responsive dynamic wetting properties.

[0057] As a preferred embodiment, in this specific implementation, the surface of the heat exchange substrate 1 is hydrophilic, making it easier for bubbles 8 to detach from the heat exchange substrate 1, and allowing the cooling medium to flow more smoothly in the channel 4, thereby helping to improve cooling efficiency. For example, the heat exchange substrate 1 can be made of copper, aluminum nitride, silicon carbide, aluminum, graphite, etc., to meet the requirements of thermal conductivity and hydrophilicity of the heat exchange substrate 1.

[0058] Based on the above description, the cooling structure 2 is made of one of the following: copper, silicon, aluminum, polytetrafluoroethylene, polyimide, polyetheretherketone, zirconium tungstate, Invar alloy, scandium fluoride, nickel-titanium alloy, and copper-zinc-aluminum alloy. Specifically, when manufacturing the cooling structure 2, one of the above-mentioned materials, such as copper, can be selected to make the cooling structure 2. Preferably, one or more of the above-mentioned materials, such as copper and aluminum, can be selected to make the cooling structure 2 in layers along the axial direction of the base column 202.

[0059] With the above settings, when water is used as the cooling medium, copper with high thermal conductivity can be used for indirect heat transfer; using aluminum to manufacture cooling structure 2 helps reduce production costs; since the chip's raw material is silicon, using silicon to manufacture cooling structure 2 helps reduce contact thermal resistance. Using polytetrafluoroethylene, polyimide, or polyetheretherketone to manufacture cooling structure 2 results in lower thermal conductivity, and in this case, cooling structure 2 mainly guides the bubbles 8. It is worth noting that when one of zirconium tungstate, Invar alloy, or scandium fluoride is used to manufacture cooling structure 2, since zirconium tungstate, Invar alloy, and scandium fluoride are all materials with negative thermal expansion, as the cooling medium temperature increases, the cross-section of the guide plate 201 gradually decreases, thus gradually increasing the cross-sectional area of ​​channel 4; conversely, as the cooling medium temperature decreases, the cross-sectional area of ​​channel 4 gradually decreases. When the cooling medium temperature is low, the cross-sectional area of ​​channel 4 is small, and there are generally fewer bubbles 8 at low temperatures. Occasionally, bubbles 8 may aggregate and grow larger. In this case, the smaller cross-sectional area of ​​channel 4 helps to compress the bubbles 8. When the temperature of the cooling medium is high, the channel 4 becomes larger, and the amount of bubbles 8 increases. The increased cross-sectional area of ​​the channel 4 facilitates the discharge of bubbles 8 from the channel 4, thereby further improving the cooling efficiency.

[0060] When either nickel-titanium alloy or copper-zinc-aluminum alloy is selected to fabricate cooling structure 2, because these alloys are shape memory metals, the cooling medium temperature is relatively low, resulting in a smaller cross-sectional area of ​​channel 4 in the martensitic state of cooling structure 2. Conversely, when the cooling medium temperature increases, causing cooling structure 2 to be in the austenitic state, the cross-sectional area of ​​channel 4 becomes larger. At lower cooling medium temperatures, bubbles 8 are generally fewer, and occasionally they aggregate and grow larger. However, at higher cooling medium temperatures, channel 4 enlarges, and the number of bubbles 8 increases. Therefore, using either nickel-titanium alloy or copper-zinc-aluminum alloy to fabricate cooling structure 2 facilitates the discharge of bubbles 8 through channel 4.

[0061] Based on the above, as an exemplary preparation method for a negative thermal expansion material, zirconium tungstate, i.e., ZrW2O8, is prepared by first accurately weighing high-purity ZrO2 and WO3 at a molar ratio of 1:2 and mixing and grinding them evenly in a ball mill. Then, the mixed powder is placed in a crucible and pre-calcined at 900°C for 12 hours to form a precursor. After sintering at 1100°C for 24 hours, a single-phase ZrWO8 crystal is generated. Preferably, hot isostatic pressing can be performed to improve the density. The material obtained by this method has stable isotropic negative thermal expansion properties.

[0062] As an exemplary preparation method for shape memory alloys, to achieve a small channel 4 area in a nickel-titanium alloy when the cooling medium is around 60°C, and a return to a larger channel 4 area when the cooling medium is above 70°C, the following steps are taken: First, a nickel-titanium alloy with a titanium content of approximately 50.8–51.0 at.% is selected. After vacuum melting, it undergoes solution treatment at 850°C and water quenching to ensure the phase transformation temperature Af is above 70°C. Subsequently, the material is manually transformed into a state with a smaller channel 4 cross-sectional area in a cold state (below Af), and then heated to a temperature above Af to return to a state with a larger channel 4 cross-sectional area. This thermo-mechanical cycling is repeated to achieve a stable bidirectional shape memory effect. Therefore, the nickel-titanium alloy is in a martensitic state at 60°C, resulting in a smaller channel 4 cross-sectional area, while an austenitic phase transformation is initiated at temperatures above Af to increase the channel 4 cross-sectional area.

[0063] Based on the above description, the replenishment section 3 includes a replenishment plate 31 disposed on the cooling structure. The replenishment plate 31 is made of one or more of the following: foamed metal, expanded polytetrafluoroethylene (ePTFE), polyimide aerogel, and porous polyetheretherketone (PEEK). It is understood that the replenishment section 3 can be made of one of the above materials, or it can be made of two or more materials, such as foamed metal and expanded polytetrafluoroethylene, forming a composite replenishment section 3 with two or more layers along the thickness direction of the replenishment plate 31. This allows the replenishment section 3 to have a porous structure, thereby enabling the working fluid in the cooling zone to permeate through the replenishment section 3.

[0064] It is worth noting that foam metals such as foamed copper, foamed aluminum, and foamed zinc can be used to achieve a porous structure in the replenishment section 3, thereby allowing the working fluid in the cold zone to pass through the replenishment section 3.

[0065] In the cooling device described in this application embodiment, as bubbles 8 form and grow within channel 4, under the constraint and guidance of the sidewalls of channel 4, bubbles 8 exhibit a shape with a small head and a large tail. That is, bubbles 8 gradually expand from the side near the first end 4a to the side near the second end 4b. As described above, bubbles 8 of this shape move in the expansion direction γ under the action of surface tension, thereby promoting the bubbles 8 to detach from channel 4 from the second end 4b under the guidance of the sidewalls of channel 4. At the same time, the more bubbles 8 generated within channel 4, the more steam is produced. The more steam, the greater the resistance of channel 4. Since flow resistance is proportional to pressure drop, the pressure of channel 4 is lower when more bubbles 8 are generated. In the liquid replenishment section 3, the cooling medium flow rate is lower, and the pressure gradient is relatively smaller. The cooling medium is transported to channel 4, which has higher resistance and lower pressure, to replenish the cooling medium within channel 4. This delays the formation of a gas film by bubbles 8, which would hinder the rewetting of the surface of the heating element 7 by the cooling medium, thus preventing a sharp deterioration in heat transfer performance and improving cooling efficiency.

[0066] Example 2

[0067] The difference between this embodiment and Embodiment 1 is that, in this embodiment, as... Figure 5 and Figure 6 As shown, preferably, the surface of the heat exchange substrate 1 with the cooling structure 2 is rectangular. In specific implementation, the preset direction β is the length or width direction of the heat exchange substrate 1; the guide plate 201 is long and narrow, and the cross-sectional area of ​​the guide plate 201 gradually decreases from the center of the guide plate 201 to both ends of the guide plate 201 along the length direction; the first end 4a is located at the center of the guide plate 201 along the length direction, and the second end 4b is located at both ends of the guide plate 201 along the length direction.

[0068] The above arrangement allows a channel 4 to have one first end 4a and two second ends 4b, meaning the same channel 4 has two openings to discharge air bubbles 8. This facilitates the replenishment of liquid into the channel 4 by the replenishment part 3, which helps to further improve cooling efficiency. Preferably, along the length of the guide plate 201, both ends of the guide plate 201 extend to the edge of the heat exchange substrate 1, and the replenishment part 3 covers the top of the guide plate 201.

[0069] It is understandable that the surface of the heat exchange substrate 1 where the cooling structure 2 is located can also be circular or other irregular shapes. If it is circular, the preset direction β can be set to any radial direction of the heat exchange substrate 1. If it is irregular, the preset direction β of the heat exchange substrate 1 only needs to be set to be perpendicular to the guide plate 201.

[0070] It is worth noting that when the surface of the cooling structure 2 on the preferred heat exchange substrate 1 is rectangular, the sides of the guide plates 201 at both ends of the cooling structure 2 that are opposite to each other along the preset direction β can be set as planes due to the limitation of the surface of the cooling structure 2 on the heat exchange substrate 1. This setting reduces the volume of the cooling structure 2 and facilitates the adjacent arrangement of multiple heat exchange substrates 1.

[0071] It is understandable that when the surface of the heat exchange substrate 1 with the cooling structure 2 is circular or other irregular in shape, the guide plates 201 at both ends of the cooling structure 2 along the preset direction β can cool the edge of the substrate by conforming to the shape.

[0072] Example 3

[0073] The difference between this embodiment and Embodiment 1 is that, in this embodiment, preferably, as follows: Figure 7 and Figure 8 As shown, the surface of the heat exchange substrate 1 with the cooling structure 2 is rectangular. In specific implementation, the preset direction β is the length or width direction of the heat exchange substrate 1. Two adjacent guide plates 201 form a group. One end of the two guide plates 201 in the same group is close to each other to form the first end 4a, and the other end is far away from each other to form the second end 4b. The first end 4a and the second end 4b of two adjacent channels 4 are arranged alternately along the preset direction β.

[0074] With the above settings, under the condition that the surface of the heat exchange substrate 1 is fixed, the length of the channel 4 is effectively increased, which in turn effectively increases the amount of bubbles 8 in the channel 4, thereby further reducing the pressure in the channel 4. This facilitates the replenishment of liquid by the replenishment unit 3 into the channel 4, which in turn helps to further improve the circulation of the cooling working fluid in the channel 4 and further improves the cooling efficiency.

[0075] It is understandable that the surface of the heat exchange substrate 1 where the cooling structure 2 is located can also be circular or other irregular shapes. If it is circular, the preset direction β can be set to any radial direction of the heat exchange substrate 1. If it is irregular, the preset direction β of the heat exchange substrate 1 only needs to be set to be perpendicular to the guide plate 201.

[0076] It is worth noting that when the surface of the heat exchange substrate 1 with the cooling structure 2 is rectangular, the sides of the guide plates 201 at both ends of the cooling structure 2 that are opposite to each other along the preset direction β can be set as planes due to the limitation of the surface of the heat exchange substrate 1 with the cooling structure 2. This setting reduces the volume of the cooling structure 2 and facilitates the adjacent arrangement of multiple heat exchange substrates 1.

[0077] It is understandable that when the surface of the heat exchange substrate 1 with the cooling structure 2 is circular or other irregular in shape, the guide plates 201 at both ends of the cooling structure 2 along the preset direction β can cool the edge of the substrate by conforming to the shape.

[0078] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A cooling device for cooling a heating element (7) within a cooling pool (6), characterized in that, The cooling device includes: A heat exchange substrate (1) capable of covering the heating element (7), a cooling structure (2) provided on the heat exchange substrate (1), and a liquid replenishment part (3) provided on the cooling structure (2) and facing away from the heat exchange substrate (1); The heat exchange substrate (1), the cooling structure (2) and the liquid replenishment part (3) form a channel (4), the channel (4) has a first end (4a) and a second end (4b), and the cross-sectional area of ​​the channel (4) gradually increases from the first end (4a) to the second end (4b) along the extension direction of the channel (4); Guided by the side wall of the channel (4), the bubbles (8) can be discharged from the second end (4b) to the outside of the channel (4), and the cooling medium in the cooling pool (6) can be replenished into the channel (4) through the replenishment part (3); The cooling structure (2) is coated with a temperature-sensitive wetting coating (5); the components of the temperature-sensitive wetting coating (5) include 1H,1H,2H,2H-perfluorodecyltrichlorosilane and TiO2.

2. The cooling device according to claim 1, characterized in that: The cooling structure (2) includes multiple guide plates (201) arranged along a preset direction (β), and two adjacent guide plates (201), the heat exchange substrate (1) and the liquid replenishment part (3) form the channel (4).

3. The cooling device according to claim 2, characterized in that: The cooling structure (2) further includes: a base column (202) disposed on the heat exchange substrate (1); The preset direction (β) is the circumferential direction of the base column (202), and the multiple guide plates (201) are distributed along the circumferential direction of the base column (202); One end of the guide plate (201) is connected to the base column (202), and the other end of the guide plate (201) extends radially toward the edge of the heat exchange substrate (1) along the base column (202).

4. The cooling device according to claim 3, characterized in that: The included angle (α) between two adjacent guide plates (201) ranges from 5° to 30°, and / or, The two adjacent guide plates (201) are distributed at equal angles.

5. The cooling device according to claim 2, characterized in that: The preset direction (β) is the length or width direction of the heat exchange substrate (1); the guide plate (201) is long and narrow, and the cross-sectional area of ​​the guide plate (201) gradually decreases from the center of the guide plate (201) to both ends of the guide plate (201) along the length direction of the guide plate (201); The first end (4a) is located at the center of the guide plate (201) along its length, and the second end (4b) is located at both ends of the guide plate (201) along its length.

6. The cooling device according to claim 2, characterized in that: The preset direction (β) is the length or width direction of the heat exchange substrate (1). Two adjacent guide plates (201) form a group. One end of the two guide plates (201) in the same group is close to each other to form the first end (4a), and the other end is far away from each other to form the second end (4b). The first end (4a) and the second end (4b) of two adjacent channels (4) are arranged alternately along the preset direction (β).

7. The cooling device according to claim 1, characterized in that: The surface of the heat exchange substrate (1) is hydrophilic.

8. The cooling device according to claim 3, characterized in that: The surface of the heat exchange substrate (1) on which the cooling structure (2) is provided is rectangular or circular; The base column (202) is located at the center of the heat exchange substrate (1), and the guide plate (201) extends from the end opposite to the base column (202) to the edge of the heat exchange substrate (1).

9. The cooling device according to claim 1, characterized in that: The replenishment section (3) includes a replenishment plate (31) disposed on the cooling structure (2), the replenishment plate (31) being made of one or more of foamed metal, expanded polytetrafluoroethylene, polyimide aerogel, and porous polyetheretherketone, and / or, The cooling structure (2) is made of one of copper, silicon, aluminum, polytetrafluoroethylene, polyimide, polyetheretherketone, zirconium tungstate, Invar alloy, scandium fluoride, nickel-titanium alloy and copper-zinc-aluminum alloy.

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