High-heat load cooling device

Abstract

The invention discloses a high heat load cooling device which comprises a heat storage type micro-channel heat sink, the heat storage type micro-channel heat sink comprises a base body, a cooling liquid inlet and a cooling liquid outlet are formed in the base body, and parallel Tesla micro-channels, a liquid storage tank and a phase change material tank are arranged in the base body; the liquid storage tanks are located on the two sides of the Tesla micro-channel and communicate with the Tesla micro-channel, the liquid storage tank on one side communicates with a cooling liquid inlet, and the liquid storage tank on the other side communicates with a cooling liquid outlet; the phase change material groove is positioned below the Tesla micro-channel; a phase-change material is arranged in the phase-change material groove, and cooling liquid flows in the Tesla micro-channel. According to the high-heat load cooling device, the response speed of a system under intermittent high-heat load is increased, the occupied space is reduced, the pressure drop of a loop working medium of the system is reduced, and the power consumption of the system is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal management of power devices, and in particular to a high heat load cooling device. Background Art

[0002] With the rapid development of electronic technology, the integration and power requirements of electronic devices are constantly increasing, and their heat flux density per unit volume is also continuing to climb. However, the operating reliability of electronic equipment is extremely sensitive to temperature changes. If effective thermal management is not carried out, it is easy to cause local overheating, which seriously affects the performance and operational safety of the equipment. In addition, in a periodically fluctuating environment, electronic equipment often faces problems such as high heat flux density, rapid temperature rise, and large thermal stress. For example, high-energy equipment such as high-speed aircraft and radars often experience high thermal loads in a short period of time (i.e., instantaneous release of high heat flux, with heat flux density reaching 500W / cm², and in extreme cases even reaching 1kW / cm², usually lasting for minutes). These equipment are characterized by short temperature control time, severe load fluctuations, and difficulty in temperature control. Therefore, how to improve the heat dissipation efficiency of electronic equipment during instantaneous operation in a limited space has become a key issue that needs to be solved urgently.

[0003] Phase change energy storage technology, due to its unique advantages such as high heat storage density, constant temperature during heat storage and release, and recyclability, has become a preferred solution for breaking through the bottleneck of reliable and efficient heat dissipation technology for intermittent heat flow and high heat load heat sources. Patent documents with publication numbers CN117015191A and CN116581093B achieve heat dissipation of devices under intermittent heat loads by adding a heat reservoir to the circuit. However, this increases the space occupied by the entire system, and the long flow path between the heat reservoir and the heat sink slows the dynamic response speed, making it difficult to adapt to the heat dissipation requirements of devices under transient high heat load conditions. Patent document with publication number CN119353989A uses a latent heat storage module with a heat sink working fluid circuit to achieve heat dissipation of electronic chips. Although the latent heat storage module is miniaturized and integrated, it still belongs to the circuit system itself, and its latent heat storage section imitates the multi-level branching hierarchy of plants. This further increases the pressure drop of the circuit working fluid flowing through the latent heat storage section, thereby increasing the power consumption of the circuit system. Therefore, how to design an intermittent high heat load cooling device with high cooling efficiency, fast response speed, compact size and low system power consumption is the technical problem to be solved by the present invention. Summary of the Invention

[0004] The technical problem to be solved by the invention is how to achieve the heat dissipation of instantaneous high-power heat generated by intermittent high-heat load devices under the conditions of low power consumption, fast response and small space occupation.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: A high heat load cooling device comprising: A thermal storage microchannel heat sink includes a substrate having a coolant inlet and a coolant outlet. Parallel Tesla microchannels, a liquid reservoir, and a phase change material tank are provided within the substrate. The liquid reservoirs are located on both sides of the Tesla microchannels and communicate with the Tesla microchannels, with the liquid reservoir on one side communicating with the coolant inlet and the liquid reservoir on the other side communicating with the coolant outlet. The phase change material tank is located below the Tesla microchannels. A phase change material is provided in the phase change material groove, and a coolant flows in the Tesla microchannel; During the instantaneous high heat load stage, the substrate surface close to the phase change material groove side acts as the heat absorption surface of the high heat load. The phase change material in the phase change material groove undergoes a melting phase change and absorbs a large amount of heat during the heating process. The melted phase change material releases heat and solidifies near the Tesla microchannel side. The coolant in the Tesla microchannel takes away the heat by boiling heat exchange. The solidified solid phase change material has a high density and sinks back to the high heat load heat source side under the action of gravity to absorb heat, and this process is repeated continuously.

[0006] In the non-thermal load stage, the phase change material in the phase change material tank absorbs a small amount of heat released by the high heat load heat source, and the coolant in the Tesla microchannel takes away the heat released by the solidification of the phase change material in the phase change material tank by boiling heat exchange. At this time, the solidification rate of the phase change material in the phase change material tank is greater than its melting rate.

[0007] A raised drop-shaped Tesla diverter island is arranged in the middle of the parallel Tesla microchannels; the upper side of the drop-shaped Tesla diverter island is parallel to the straight channel of the upper Tesla unit, and the lower side of the drop-shaped Tesla diverter island is parallel to the straight channel of the lower Tesla unit, and the angle α formed between the two sides ranges from 0 to 90°; when the steam passes through the drop-shaped Tesla diverter island, the main channel is divided into two channels, and the flow direction of the steam changes after entering the Tesla bend, resulting in momentum loss and suppressing the backflow phenomenon of the steam.

[0008] The phase change material groove is provided with micro-ribs at equal intervals. The arrangement of micro-ribs in the phase change material groove can increase the heat exchange area between the phase change material and the microchannel heat sink, effectively reducing the thermal resistance in the phase change material groove.

[0009] The equivalent diameter D1 of the micro-ribs, the distance D2 between the micro-ribs, and the distance D3 between the micro-ribs and the phase change material groove wall satisfy the following conditions: 2D3+iD1+(i-1)D2=a 2D3+jD1+(j-1)D2=b Wherein, a and b represent the length and width of the phase change material slot, respectively; i and j represent the number of micro-ribs in the length and width directions of the phase change material slot, respectively; i > 2, j > 1.

[0010] By arranging micro-ribs in the phase change material groove, the heat exchange area between the phase change material and the microchannel heat sink can be increased, which effectively improves the melting rate of the phase change material in the phase change material groove and the heat exchange efficiency with the microchannel heat sink.

[0011] The micro-ribs are cylindrical, conical or square.

[0012] The micro-ribs in the phase change material groove are bionic palm-shaped leaf-shaped fin micro-ribs with multiple layers of bionic palm-shaped leaf-shaped fins;

[0013] The length L of the upper palm leaf of the multi-layer bionic palm leaf fin n The length of the palmate leaf of the next layer is L n-1 The relationship between L n =1 / 2L n-1 , the width of the upper palmate leaf w n The width of the palmate leaf of the next layer is w n-1 The relationship between w n =1 / 2w n-1 , n is the number of layers. The micro-ribs with biomimetic palm-shaped wings can further increase the heat exchange area between the phase change material and the microchannel heat sink, thereby improving the heat exchange efficiency.

[0014] The coolant is water, R134a, methanol, ethanol or propanol.

[0015] The thermal storage microchannel heat sink also includes an upper cover plate and a lower cover plate. The upper cover plate is positioned above the liquid reservoir and Tesla microchannels to seal the coolant flowing through the Tesla microchannels. The lower cover plate is positioned above and below the phase change material tank to seal the phase change material within the phase change material tank. The high heat load cooling device also includes a condenser, a liquid reservoir, and a mechanical pump. The coolant in the reservoir flows through the mechanical pump, the thermal storage microchannel heat sink, and the condenser, forming a circulation system.

[0016] The advantages of the present invention are: (1) The thermal storage Tesla microchannel heat sink established by the present invention integrates the heat storage device in the traditional thermal storage cooling system loop into the microchannel heat sink, making it a whole. This improves the system's response speed under intermittent high heat loads and reduces the occupied space. In addition, by eliminating the flow process of the circuit working fluid in the complex flow channel of the heat storage device, the invented high heat load cooling device reduces the pressure drop of the system's circuit working fluid and reduces the system power consumption.

[0017] (2) Compared with the traditional straight channel microchannel heat sink, the present invention adopts the Tesla microchannel heat sink, which increases the contact area between the coolant and the channel and enhances the heat exchange efficiency. In addition, the diverter island structure in the Tesla microchannel causes the steam to divert and change the flow direction when flowing through the Tesla bend, resulting in momentum loss. Therefore, the periodically evenly distributed Tesla units and the diverter island structure in the main channel jointly suppress the steam backflow phenomenon.

[0018] (3) The phase change material grooves in the heat storage microchannel heat sink established this time are arranged with micro-ribs at equal intervals. This not only increases the heat exchange area between the phase change material and the microchannel heat sink, but also effectively reduces the thermal resistance in the phase change material grooves, solving the problem of untimely heat dissipation of high heat load heat sources caused by insufficient thermal conductivity of the phase change material under instantaneous high heat loads.

[0019] (4) The micro-ribs in the phase change material grooves of the heat storage microchannel heat sink established this time are micro-ribs with bionic palm-shaped fins, which can further increase the heat exchange area between the phase change material and the microchannel heat sink and improve the heat exchange efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of a high heat load cooling device in Example 1 of the present invention; Figure 2 Schematic diagram of a heat storage type microchannel heat sink and a high heat load heat source in Example 1 of the present invention; Figure 3 Schematic diagram of a cross section of a thermal storage microchannel heat sink in Example 1 of the present invention; Figure 4 1 is a top view of Tesla microchannels arranged in parallel and at equal intervals in Example 1 of the present invention; Figure 5 Schematic diagram of the flow path of a Tesla-type microchannel containing a drop-shaped Tesla diverter island in Example 1 of the present invention; Figure 6 1 is a top view of a cylindrical micro-rib phase change material groove in Example 1 of the present invention; Figure 7 This is a schematic diagram of a method for constructing a bionic palm-shaped leaf fin in Example 1 of the present invention; Figure 8 A top view of a phase change material slot with bionic palm-shaped fin micro-ribs in the first embodiment of the present invention; Figure 9 for Figure 8 Cross-sectional view of the micro-rib column in the bionic palm-shaped leaf fin. DETAILED DESCRIPTION

[0021] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by any person skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0022] Example 1 like Figure 1 As shown, the present invention provides a high heat load cooling device, such as Figure 1 As shown, the system comprises a thermal storage microchannel heat sink 1, a condenser 3, a liquid storage tank 4, a mechanical pump 5, and a high-heat-load heat source 2. The coolant in the liquid storage tank 4 flows through the mechanical pump 5, the thermal storage microchannel heat sink 1, and the condenser 3, forming a circulation system. The high-heat-load heat source 2 is arranged below the channel structure of the thermal storage microchannel heat sink 1. The coolant absorbs the heat released by the high-heat-load heat source 2 in the channel structure and undergoes boiling heat exchange. The coolant uses R134a.

[0023] like Figure 2 and 3 As shown, the heat storage type microchannel heat sink 1 includes an upper cover plate 11, a lower cover plate 12, a coolant inlet 13, a coolant outlet 14, parallel Tesla microchannels 15, a liquid reservoir 16 and a phase change material tank 17. The liquid reservoir 16 is located below the coolant inlet 13 and the coolant outlet 14 and is connected to the Tesla microchannel 15. The upper cover plate 11 is used to seal the coolant flowing through the Tesla microchannel 15. The phase change material tank 17 is located below the Tesla microchannel 15. The protrusions around the lower cover plate 12 are in contact with the phase change material tank 17 to seal the phase change material in the phase change material tank 17. The high heat load heat source 2 is located below the lower cover plate 12.

[0024] During the instantaneous high heat load stage, heat is first transferred to the phase change material groove 17 through the high heat load heat source 2. The phase change material in the phase change material groove 17 near the high heat load heat source 2 undergoes a melting phase change during the heating process, absorbing a large amount of heat. The melted phase change material releases heat and solidifies on the side near the Tesla microchannel 15. The coolant in the Tesla microchannel 15 takes away the heat by boiling heat exchange. The solidified solid phase change material has a high density and sinks back to the side of the high heat load heat source 2 under the action of gravity to absorb heat. This process is repeated continuously.

[0025] In the non-thermal load stage, the phase change material in the phase change material groove 17 absorbs a small amount of heat released by the high heat load heat source 2, and the coolant in the Tesla microchannel 15 takes away the heat released by the solidification of the phase change material in the phase change material groove 17 by boiling heat exchange. At this time, the solidification rate of the phase change material in the phase change material groove 17 is greater than its melting rate.

[0026] like Figure 4 and 5 As shown, a raised drop-shaped Tesla diverter island 151 is arranged in the middle of the parallel and equally spaced Tesla microchannels 15. The upper side of the drop-shaped Tesla diverter island 151 is parallel to the straight channel of the upper Tesla unit, and the lower side of the drop-shaped Tesla diverter island 151 is parallel to the straight channel of the lower Tesla unit. The angle α formed between the two sides is 30°. When the steam passes through the drop-shaped Tesla diverter island 151, the main channel is divided into two channels. After the steam enters the Tesla bend, the flow direction changes, resulting in momentum loss, thereby significantly suppressing the backflow phenomenon of the steam.

[0027] like Figure 6 As shown, micro-ribs 171 are arranged at equal intervals in the phase change material groove 17. The micro-ribs 171 are cylindrical, the equivalent diameter of the micro-ribs 171 is 1 mm, the distance between the micro-ribs 171 is 4 mm, the distance between the micro-ribs 171 and the wall of the phase change material groove 17 is 2 mm, and the length and width of the phase change material groove 17 are 50 mm and 20 mm respectively. The arrangement of the micro-ribs 171 in the phase change material groove 17 can reduce the lateral flow of the phase change material when it melts, while increasing the heat exchange area between the phase change material and the microchannel heat sink, thereby improving the melting and solidification rates of the phase change material.

[0028] like Figure 7 As shown, the bionic palm-shaped fin has a self-affine characteristic on each bifurcation layer, and the length of the palm-shaped leaf on the previous layer is L n The length of the palmate leaf of the next layer is L n-1 The relationship between L n =1 / 2L n-1 , the width of the upper palmate leaf w n The width of the palmate leaf of the next layer is w n-1 The relationship between w n =1 / 2w n-1 , n is the number of layers. Figure 8 、 Figure 9 As shown, the micro-ribs with multiple layers of bionic palm-leaf-shaped fins within phase-change material slot 17 are bionic palm-leaf-shaped fin micro-ribs 172 (n=1). For these multi-layer bionic palm-leaf-shaped fins, the length and width are 0.59 mm and 0.43 mm, respectively, when n=0, and 0.29 mm and 0.21 mm, respectively, when n=1. These bionic palm-leaf-shaped fin micro-ribs 172 can further increase the heat exchange area between the phase-change material and the microchannel heat sink, improving heat exchange efficiency.

[0029] 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 aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications and replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high heat load cooling device, characterized in that: include: A thermal storage microchannel heat sink includes a substrate having a coolant inlet and a coolant outlet. Parallel Tesla microchannels, a liquid reservoir, and a phase change material tank are provided within the substrate. The liquid reservoirs are located on both sides of the Tesla microchannels and communicate with the Tesla microchannels, with the liquid reservoir on one side communicating with the coolant inlet and the liquid reservoir on the other side communicating with the coolant outlet. The phase change material tank is located below the Tesla microchannels. A phase change material is provided in the phase change material groove, and a coolant flows in the Tesla microchannel; During the instantaneous high heat load stage, the substrate surface close to the phase change material slot acts as a heat absorption surface for the high heat load. The phase change material in the phase change material slot undergoes a melting phase change during the temperature rise process and absorbs a large amount of heat. The melted phase change material releases heat and solidifies near the Tesla microchannel. The coolant in the Tesla microchannel takes away the heat by boiling heat exchange. The solidified solid phase change material, due to its high density, sinks back to the high heat load heat source side under the action of gravity to absorb heat, and this process is repeated continuously. In the non-thermal load stage, the phase change material in the phase change material tank absorbs a small amount of heat released by the high heat load heat source, and the coolant in the Tesla microchannel takes away the heat released by the solidification of the phase change material in the phase change material tank by boiling heat exchange. At this time, the solidification rate of the phase change material in the phase change material tank is greater than the melting rate of the phase change material.

2. A high heat load cooling device according to claim 1, characterized in that: A raised drop-shaped Tesla diverter island is arranged in the middle of the parallel Tesla microchannels; the upper side of the drop-shaped Tesla diverter island is parallel to the straight channel of the upper Tesla unit, and the lower side of the drop-shaped Tesla diverter island is parallel to the straight channel of the lower Tesla unit, and the angle α formed between the two sides ranges from 0 to 90°; when the steam passes through the drop-shaped Tesla diverter island, the main channel is divided into two channels, and the flow direction of the steam changes after entering the Tesla bend, resulting in momentum loss and suppressing the backflow phenomenon of the steam.

3. The high heat load cooling device according to claim 1, characterized in that: Micro-ribs with equal spacing are arranged in the phase change material grooves.

4. A high heat load cooling device according to claim 3, characterized in that: The equivalent diameter D1 of the micro-ribs, the distance D2 between the micro-ribs, and the distance D3 between the micro-ribs and the phase change material groove wall satisfy the following conditions: 2D3+iD1+(i-1)D2=a 2D3+jD1+(j-1)D2=b Wherein, a and b represent the length and width of the phase change material slot, respectively; i and j represent the number of micro-ribs in the length and width directions of the phase change material slot, respectively, i>2, j>1.

5. A high heat load cooling device according to claim 4, characterized in that: The micro-ribs are cylindrical, conical or square.

6. A high heat load cooling device according to claim 4, characterized in that: The micro-rib column in the phase change material groove is a bionic palm-shaped leaf-shaped fin micro-rib column with multiple layers of bionic palm-shaped leaf-shaped fins; the length of the upper layer of the multi-layer bionic palm-shaped leaf-shaped fin is L n The length of the palmate leaf of the next layer is L n-1 The relationship between L n =1 / 2L n-1 , the width of the upper palmate leaf w n The width of the palmate leaf of the next layer is w n-1 The relationship between w n =1 / 2w n-1 , n is the number of layers.

7. A high heat load cooling device according to any one of claims 1 to 6, characterized in that: The coolant is water, R134a, methanol, ethanol or propanol.

8. A high heat load cooling device according to any one of claims 1 to 6, characterized in that: The thermal storage type microchannel heat sink also includes an upper cover plate and a lower cover plate; the upper cover plate is arranged above the liquid storage tank and the Tesla microchannel, and is used to seal the coolant flowing through the Tesla microchannel; the lower cover plate is arranged below the phase change material tank, and is used to seal the phase change material in the phase change material tank.

9. A high heat load cooling device according to any one of claims 1 to 6, characterized in that: Also includes: Condenser, liquid storage tank and mechanical pump; the coolant in the liquid storage tank flows through the mechanical pump, thermal storage type microchannel heat sink and condenser to form a cycle.

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