Efficient heat dissipation cold plate integrated with porous metal separator

Abstract

The efficient heat dissipation cold plate comprises a cold plate body, an inlet set and an outlet set, the inlet set and the outlet set are arranged at the two ends of the cold plate body, the multiple porous metal separators are arranged in a cavity of the cold plate body at intervals in parallel, and the cavity of the cold plate body is divided into multiple flow channels by the porous metal separators; the two ends of each flow channel are communicated with the inlet set and the outlet set respectively, the adjacent flow channels are communicated through through holes formed in the porous metal separators, and a working medium enters the cold plate body from an inlet of the inlet set, enters the different flow channels after being divided or converged repeatedly in the through holes and finally flows out of the cold plate body from an outlet of the outlet set. By arranging the porous metal separators, a working medium flows through the porous metal network structure, a turbulent flow effect is generated in the flowing process, the heat exchange coefficient and the heat exchange efficiency in the cold plate are remarkably improved, the excellent heat dissipation performance of the cold plate is ensured, the operation cost is remarkably reduced, and the overall efficiency of a heat management system is improved.

Description

Technical Field

[0001] The invention relates to the field of thermal management technology, and in particular to a high-efficiency heat dissipation cold plate with an integrated porous metal separator. Background Art

[0002] With the continuous advancement of modern electronic technology, high-power, high-integration electronic components (such as electric vehicle control units, server CPU / GPU, power module new energy power converters, etc.) have been widely used in various fields. However, when electronic components are under high load or work for a long time, they will release a lot of heat. If they cannot be dissipated in time, it will lead to component performance degradation, shortened life, and even safety risks. Therefore, thermal management of various high-power electronic components has become a key link to ensure system stability and reliability.

[0003] In the prior art, liquid cooling technology is widely used in the heat dissipation system of electronic components because of its high heat exchange efficiency, flexible layout, safety and reliability. Among them, the cold plate is a common heat dissipation structure in liquid cooling technology. The working principle is to allow the coolant to take away the heat generated by the heat source when it is working in the flow channel, and transfer the heat from the vicinity of the heat source to the radiator or other heat exchange device through circulation. Traditional cold plates mostly adopt simplified straight channels, serpentine channels or parallel channels. Although the structure is simple and the processing is convenient, there are often some shortcomings, such as uneven fluid distribution. When the coolant reaches the downstream of the flow channel from the inlet, the temperature continues to rise, resulting in the attenuation of the heat exchange capacity in the local area, and it is easy to have problems such as uneven temperature distribution and local overheating; the heat dissipation capacity is limited, and the heat transfer is simply dependent on the channel surface area. The heat exchange efficiency is limited, and it is difficult to meet the needs of high-power or concentrated heating components; the flow power consumption is large. If too complex or dense flow channels are used to increase the heat exchange area or enhance the turbulence, the flow resistance will be significantly increased, thereby increasing the power consumption of the circulation pump and increasing the operating cost.

[0004] Therefore, how to improve heat dissipation efficiency without significantly increasing energy consumption and operating costs has become a difficult problem waiting to be solved in this field. Summary of the invention

[0005] The present invention provides a high-efficiency heat dissipation cold plate with an integrated porous metal separator to solve the above problems.

[0006] In order to achieve the above object, the technical solution of the present invention is:

[0007] An efficient heat dissipation cold plate integrated with a porous metal separator, comprising a cold plate main body, an inlet group and an outlet group arranged at both ends of the cold plate main body. A plurality of porous metal separators are arranged at intervals and in parallel in the cavity of the cold plate main body. The porous metal separators divide the cavity of the cold plate main body into a plurality of flow channels. Both ends of the flow channels are respectively communicated with the inlet group and the outlet group. Adjacent flow channels are communicated through through holes arranged on the porous metal separators. The working medium enters the cold plate main body from the inlet of the inlet group, and after repeatedly diverging or converging in the through holes, enters different flow channels, and finally flows out of the cold plate main body from the outlet of the outlet group.

[0008] Further, the inlet and the outlet are arranged in a staggered manner at both ends of the cold plate main body, so that adjacent inlets and outlets are respectively arranged on both sides of the porous metal separator.

[0009] Further, the porosity of the through holes of the porous metal separator is 70% - 95%, and the pore diameter density of the through holes is 10 - 80 PPI.

[0010] Further, the porosity or pore diameter density of the through holes gradually decreases from the inlet group to the outlet group direction, or gradually decreases from top to bottom along the thickness direction of the porous metal separator.

[0011] Further, the porosity of the through holes at any position on the porous metal separator is equal, and the pore diameter density of the through holes at any position on the porous metal separator is equal.

[0012] Further, the material of the porous metal separator is heat-conducting metal aluminum, nickel, copper or their alloys.

[0013] Further, the working medium is a liquid coolant, and the liquid coolant is selected from any one of water, ethylene glycol aqueous solution, dielectric coolant, hydrocarbon and silicone coolant, and fluorinated coolant.

[0014] Further, the porous metal separator is installed in the cold plate main body by brazing, press-fitting or mechanical fixing methods.

[0015] The beneficial effects of the present invention are:

[0016] An efficient heat dissipation cold plate integrated with a porous metal separator disclosed in the present invention forces the working fluid to flow through the porous metal network structure, generating a turbulent flow effect during the flow process, avoiding the situation where the working fluid directly flows through the cold plate without passing through the heat exchange structure, ensuring that the working fluid fully contacts the heat exchange surface inside the cold plate, improving the uniformity of the temperature distribution inside the cold plate, significantly enhancing the heat transfer coefficient and heat transfer efficiency inside the cold plate, and ensuring excellent heat dissipation performance of the cold plate; compared with the existing cold plate, it significantly reduces the flow power consumption under the same heat dissipation capacity, significantly reduces the operating cost, and improves the overall efficiency of the thermal management system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0018] Figure 1 Schematic diagram of the structure of an efficient heat dissipation cold plate integrated with a porous metal separator and the working fluid flow path disclosed in Embodiment 1 of the present invention Figure 1 ;

[0019] Figure 2 Schematic diagram of the working fluid flow path inside an efficient heat dissipation cold plate integrated with a porous metal separator disclosed in Embodiment 1 of the present invention Figure 2 (Top view of the lower plate surface);

[0020] Figure 3 Schematic diagram of the working fluid flow path inside an efficient heat dissipation cold plate integrated with a porous metal separator disclosed in Embodiment 2 of the present invention Figure 1 ;

[0021] Figure 4 Schematic diagram of the working fluid flow path inside an efficient heat dissipation cold plate integrated with a porous metal separator disclosed in Embodiment 2 of the present invention Figure 2 (Top view of the lower plate surface);

[0022] Figure 5 Schematic diagram of the working fluid flow path inside an efficient heat dissipation cold plate integrated with a porous metal separator disclosed in Embodiment 3 of the present invention Figure 1 ;

[0023] Figure 6 Schematic diagram of the working fluid flow path inside an efficient heat dissipation cold plate integrated with a porous metal separator disclosed in Embodiment 3 of the present invention Figure 2 (Top view of the lower plate surface);

[0024] Figure 7It is a schematic structural diagram of a straight-channel cold plate;

[0025] Figure 8 It is a schematic diagram of the position of an efficient heat dissipation cold plate integrated with a porous metal separator and a battery pack disclosed in Embodiment 1 of the present invention;

[0026] Figure 9 It is a comparison chart of temperature curves of Embodiment 1, Embodiment 2, Embodiment 3 of the present invention and a straight-channel cold plate for heat dissipation of a battery pack;

[0027] Figure 10 It is a comparison chart of power consumption curves of Embodiment 1, Embodiment 2, Embodiment 3 of the present invention and a straight-channel cold plate for heat dissipation of a battery pack;

[0028] Figure 11 It is a schematic diagram of the temperature field of Embodiment 1, Embodiment 2, Embodiment 3 of the present invention and a straight-channel cold plate for heat dissipation of a battery pack.

[0029] In the figure:

[0030] 1. Cold plate main body;

[0031] 2. Porous metal separator;

[0032] 3. Flow channel;

[0033] 21. Through hole;

[0034] 4. Inlet

[0035] 5. Outlet;

[0036] 6. Straight-channel cold plate; 61. Straight channel; 62. Straight-channel inlet; 63. Straight-channel outlet;

[0037] 7. Battery pack. Detailed implementation manners

[0038] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0039] Embodiment 1:

[0040] As Figure 1-2As shown in the figure, an efficient heat dissipation cold plate integrated with a porous metal separator includes a cold plate body 1, an inlet group and an outlet group provided at both ends of the cold plate body 1. A plurality of porous metal separators 2 are arranged in the cavity of the cold plate body 1 at intervals and in parallel. The porous metal separators 2 divide the cavity of the cold plate body 1 into a plurality of flow channels 3. Both ends of the flow channels 3 are respectively communicated with the inlet group and the outlet group. Adjacent flow channels 3 are communicated through through holes 21 provided on the porous metal separators 2. The working medium enters the cold plate body 1 from the inlet 4 of the inlet group, and after repeated diversion or confluence in the through holes 21, enters different flow channels 3, and finally flows out of the cold plate body 1 from the outlet 5 of the outlet group.

[0041] Preferably, the inlet 4 and the outlet 5 are arranged in a staggered manner at both ends of the cold plate body 1, so that the adjacent inlet and outlet are respectively arranged on both sides of the porous metal separator 2. The working medium flows into the cold plate body 1 through the inlet 4 on one side of the porous metal separator 2 and enters the flow channel 3, and then converges and separates with the working medium in the adjacent flow channel 3 through the through hole 21 on the porous metal separator 2, and then flows out of the cold plate body 1 through the outlet 5 on the other side or other positions of the porous metal separator 2. The cold plate body 1 is a layered structure, and an internal cavity is formed by stacking upper and lower plates. The external dimensions are approximately 315mm×173mm×12mm (length×width×height). The number of inlets in the inlet group is 5, so there are 5 parallel inlet channels communicated with the inlets. The working medium entering the cold plate body through the inlets is divided into 5 paths. The number of outlets in the outlet group is 4, so there are 4 parallel outlet channels communicated with the outlets. The working medium in the cold plate body converges into 4 paths and flows out through the outlets. The cross-sectional width of each of the above 5 parallel channels is approximately 10mm and the height is approximately 8mm, and the flow channel length is approximately 305mm. The cross-sectional width of each of the above 4 parallel flow channels is also approximately 10mm and the height is approximately 8mm, and the flow channel length is approximately 305mm.

[0042] Preferably, the porous metal separator 2 is an integrally embedded structure made of aluminum foam and is installed in the cold plate body 1 by a press-fit method. The thickness of the porous metal separator 2 is about 8 mm, and it is in close contact with the inner wall of the cold plate cavity along its outer peripheral edge; the through holes 21 are obliquely arranged, which can increase the flow path of the working fluid in the through holes, thereby improving the heat exchange effect; the porosity of the through holes 21 is 70-95%, and the pore density of the through holes 21 is 10-80 PPI (PPI, Pores Per Inch, the number of pores per inch. The lower the PPI value, the larger the pore diameter, and the relatively sparse the pore distribution. The higher the PPI value, the smaller the pore diameter, and the denser the pore distribution); the porosity of the through holes 21 at any position on the porous metal separator 2 is equal, and the pore density at any position on the porous metal separator 2 is equal. In this embodiment, the pore density of the through holes 21 is 40 PPI, and the porosity is about 80%;

[0043] Preferably, the working fluid is water, and it can also be set as other coolants according to actual usage requirements. The working fluid can produce a similar slip effect between the porous metal structure and the channel wall surface, thereby reducing the frictional resistance of the channel wall surface and improving the heat exchange efficiency without significantly increasing the pressure drop.

[0044] In this embodiment, through the 5-way parallel separation of the inlet channel group and the 4-way confluence design of the outlet channel group, the total heat exchange area of the internal channels of the cold plate is increased, and the flow rate of the coolant in the unit channel is reduced, thereby effectively controlling the flow resistance while improving the heat exchange efficiency;

[0045] By arranging the porous aluminum foam separator 2 between the inlet channel group and the outlet channel group, the coolant forms multi-directional turbulent flow when flowing through the separator, significantly enhancing the heat exchange between the coolant and the cold plate wall surface, and further improving the heat exchange efficiency of the cold plate;

[0046] The uniform pore structure of the porous separator makes the distribution of the coolant in the cold plate more uniform, and the coolant between the channels penetrates and blends with each other, avoiding local hot spots and ensuring the overall heat dissipation uniformity of the cold plate.

[0047] Therefore, compared with the existing cold plates, under the same heat dissipation capacity, the cold plate of this embodiment has lower flow resistance and better temperature uniformity.

[0048] Embodiment 2:

[0049] The difference between this embodiment and Embodiment 1 is only that, in this embodiment, as Figure 3-4As shown in the figure, the number of inlets in the inlet group is 4, and there are 4 parallel inlet channels connected to the inlets. The working medium entering the cold plate body through the inlets is divided into 4 paths. The working medium enters the cold plate body through the inlets and passes through the porous metal separator 2 provided. The number of outlets in the outlet group is 5, and there are 5 parallel outlet channels connected to the outlets. The working medium converges into 5 paths and flows out of the cold plate body through the outlets;

[0050] In this embodiment, by increasing the flow channel density on the outlet side, the collection efficiency of the coolant is enhanced, the flow accumulation and resistance fluctuation in the local outlet area are reduced, which helps to improve the overall operation stability of the system.

[0051] Embodiment 3:

[0052] As Figure 5-6 shown, the difference between this embodiment and Embodiment 1 is that in this embodiment, the porous metal separator is evenly divided into four consecutive different pore parts along the flow direction of the working medium, and the porosity of each part from the inlet to the outlet is 95%, 90%, 80% and 70% in turn.

[0053] In this embodiment, by gradually reducing the porosity, the flow velocity and turbulence intensity of the coolant flowing through different regions in the cold plate are effectively controlled, thereby achieving lower flow resistance in the inlet region and optimizing the heat transfer performance in the outlet region. On the inlet side, the higher porosity results in smaller flow resistance, facilitating the rapid filling of the internal flow channel space of the cold plate by the coolant and reducing the overall flow resistance; on the outlet side, as the porosity decreases, the turbulence effect of the coolant is enhanced, significantly improving the heat exchange efficiency between the coolant and the porous metal separator, thereby further enhancing the heat dissipation effect in the outlet region and ensuring the overall heat dissipation uniformity of the cold plate.

[0054] Adopting the above-mentioned gradually changing porosity design, compared with Embodiment 1 and Embodiment 2, this embodiment further improves the flow field uniformity in the cold plate and the heat exchange effect in the outlet region, while effectively reducing the pressure drop and energy consumption of the system operation, and is more suitable for thermal management application scenarios with high requirements for temperature field uniformity and energy consumption, such as heat dissipation management of high-performance battery modules or high-power electronic components.

[0055] Performance test and comparative analysis:

[0056] To verify the effect of the present invention in improving the battery heat dissipation performance, the CFD numerical simulation method is used to test the temperature of the battery pack 7 at the end of discharge under the actions of Embodiment 1, Embodiment 2 and Embodiment 3 proposed by the present invention. The schematic diagram of the position of the high-efficiency heat dissipation cold plate integrated with the porous metal separator and the battery pack is as Figure 8 shown, and a traditional straight-channel cold plate is used for comparison. The structural schematic diagram of the straight-channel cold plate 6 is as Figure 7As shown in the figure, the two ends of the straight flow channel 61 are the straight flow channel inlet 62 and the straight flow channel outlet 63 respectively. The thickness of the straight flow channel cold plate is the same as that of the cold plate main body in Embodiment 1, Embodiment 2 and Embodiment 3, which is 12 mm. The numerical simulation software is Ansys Fluent, and the calculation model is a three-dimensional transient laminar incompressible model. The flow channel inlet adopts a constant mass flow rate inlet, and the inlet mass flow rates are 8 g / s, 16 g / s, 24 g / s, 32 g / s, 40 g / s respectively. The inlet temperature is 298.15 K, and the outlet adopts a pressure boundary. The battery discharge rate is 5C, the discharge time is 720 s, and the initial temperature is 298.15 K.

[0057] Under the above simulation conditions, the maximum temperature of the battery pack of the traditional straight flow channel cold plate and the battery packs of Embodiments 1-3 proposed by the present invention changes with the mass flow rate as Figure 9 shown. It can be seen from the figure that when using the traditional straight flow channel cold plate for heat dissipation, the maximum temperature of the battery pack is higher than the other two cases. When the mass flow rate is 24 g / s, the maximum temperature of the battery pack of the straight flow channel cold plate is 325.59 K, while those of Embodiment 1, Embodiment 2 and Embodiment 3 are only 322.42 K, 322.48 K and 320.94 K respectively, which are relatively reduced by 3.17 K, 3.11 K and 4.65 K compared with the straight flow channel respectively.

[0058] At the same time, the results of the power consumption curve of battery heat dissipation are as Figure 10 shown. It can be seen from the figure that the power consumption of the battery pack using the straight flow channel cold plate is 0.24 mW, and the power consumptions of Embodiment 1, Embodiment 2 and Embodiment 3 are 0.28 mW, 0.22 mW and 0.08 mW respectively. The power consumption of Embodiment 3 is the lowest, and that of Embodiment 2 is the second lowest.

[0059] The temperature distribution of the battery pack under four cooling conditions is as Figure 11 shown (where the mass flow rate is 24 g / s). It can be seen from the figure that when using the straight flow channel cold plate, the overall temperature of the battery pack is higher and the temperature change is larger. While when using the cold plate with an integrated porous metal separator in Embodiment 1, Embodiment 2 and Embodiment 3, the overall temperature of the battery is lower, the temperature gradient is smaller, and the temperature distribution is more uniform.

[0060] According to the above simulation results, it can be known that under the action of the cold plate with an integrated porous metal separator disclosed in the present invention, the maximum temperature of the battery pack is significantly lower than that of the traditional straight flow channel cold plate, the temperature uniformity is improved, and the power consumption is greatly reduced, which proves that the cold plate structure proposed by the present invention can significantly improve the battery temperature with less power consumption. Among them, Embodiment 1 and Embodiment 2 can achieve lower battery temperature and uniformity, while Embodiment 3 can achieve lower pressure drop and power consumption while significantly reducing the battery temperature.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An efficient heat dissipation cold plate integrated with a porous metal separator, characterized in that, It includes a cold plate body (1), an inlet group and an outlet group provided at both ends of the cold plate body (1). A plurality of porous metal separators (2) are spaced and parallelly arranged in the cavity of the cold plate body. The porous metal separators (2) divide the cavity of the cold plate body (1) into a plurality of flow channels (3). Both ends of the flow channels (3) are respectively communicated with the inlet group and the outlet group. Adjacent flow channels (3) are communicated through through holes (21) provided on the porous metal separators (2). The working fluid enters the cold plate body (1) from the inlet (4) of the inlet group, and after repeatedly diverging or converging in the through holes (21), enters different flow channels (3), and finally flows out of the cold plate body (1) from the outlet (5) of the outlet group.

2. The highly efficient heat dissipation cold plate with an integrated porous metal separator according to claim 1, characterized in that, The inlet (4) and the outlet (5) are arranged in a staggered manner at both ends of the cold plate body (1), so that adjacent inlets (4) and outlets (5) are respectively arranged on both sides of the porous metal separator (2).

3. The highly efficient heat dissipation cold plate with an integrated porous metal separator according to claim 1, characterized in that, The porosity of the through holes (21) of the porous metal separator (2) is 70-95%, and the pore diameter density of the through holes (21) is 10-80 PPI.

4. The highly efficient heat dissipation cold plate with an integrated porous metal separator according to claim 1, characterized in that, The porosity or pore diameter density of the through holes (21) gradually decreases from the inlet group to the outlet group direction, or gradually decreases from top to bottom along the thickness direction of the porous metal separator (2).

5. The high-efficiency heat dissipation cold plate integrated with a porous metal separator according to claim 1, characterized in that, The porosity of the through holes (21) at any position on the porous metal separator (2) is equal, and the pore diameter density of the through holes (21) at any position on the porous metal separator (2) is equal.

6. The highly efficient heat dissipation cold plate with an integrated porous metal separator according to claim 1, characterized in that, The material of the porous metal separator (2) is heat-conducting metal aluminum, nickel, copper or their alloys.

7. The highly efficient heat dissipation cold plate with an integrated porous metal separator according to claim 1, characterized in that, The working fluid is a liquid coolant, and the liquid coolant is selected from any one of water, ethylene glycol aqueous solution, dielectric coolant, hydrocarbon and silicone-based coolant, and fluorinated coolant.

8. The highly efficient heat dissipation cold plate with an integrated porous metal separator according to claim 1, characterized in that The porous metal separator (2) is installed in the cold plate body (1) by brazing, press-fitting or mechanical fixing.

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