A microchannel heat dissipation integrated system for an array heat source with low thermal resistance and low pumping power

Abstract

A microchannel heat dissipation integrated system for an array heat source with low thermal resistance and low pumping power belongs to the field of enhanced heat transfer. It includes a three-layer structure, namely a top plate (1), a flow distribution plate (2), and a bottom plate (3) in sequence. The back of the flow distribution plate is processed with a fluid inlet (4), a liquid inlet flow distribution channel (6), a liquid injection hole (8), a primary H-shaped flow distribution channel branch (13), a secondary H-shaped flow distribution channel branch (14), and an end channel (15); the front is processed with a fluid outlet (5), a liquid outlet confluence channel (7), microchannels (9), a liquid storage area channel (10), a confluence channel branch (12), a primary H-shaped flow distribution channel branch (13), a secondary H-shaped flow distribution channel branch (14), and a liquid collection channel (16). Multiple heat sources (11) are arranged in an array on the top plate (1), and the flow distribution plate (2) is welded between the top plate (1) and the bottom plate (3) to form a complete system. The present invention adopts a "two-in and three-out" structure for each heat source, shortening the flow length of the fluid in the microchannels, suppressing the accumulation of heat at the end of the flow channels, and improving the temperature uniformity on the surface of the heat source. The channels in the system adopt the symmetry principle to ensure the uniformity of fluid distribution in the system, which is beneficial to dissipating heat from multiple heat sources simultaneously.

Description

Technical Field

[0001] The present invention belongs to the field of enhanced heat transfer, and designs a microchannel heat dissipation integrated system for an array heat source with low thermal resistance and low pump power. Background Art

[0002] With the rapid development of industrial technologies, various industrial products tend to develop towards high power, high integration, and light weight. The instantaneous heat flux density of microelectronic devices has exceeded 10 6 W / m 2 . If heat cannot be dissipated in a timely and effective manner, it will seriously affect the stability and service life of electronic devices. The heat dissipation problem of high heat flux density electronic devices has become an important factor restricting the development of high-tech. Traditional heat dissipation methods can no longer meet the growing heat dissipation requirements. Microchannel heat sinks have been favored by experts and scholars at home and abroad since their emergence due to their advantages such as large heat transfer coefficient, large specific surface area, light weight, small volume, and the ability to be directly integrated on heat dissipation chips. Microchannels are widely used in the microelectronics industry, air conditioners, the aviation industry and other fields.

[0003] During the process of fluid taking away heat through a microchannel, due to continuous heat absorption along the flow direction, heat accumulation will occur at the end of the flow, resulting in an increasing temperature along the fluid flow direction and forming a "hot spot" at the end of the channel, which deteriorates heat transfer. And in the application background of microelectromechanical systems, heat dissipation components such as chips often do not exist alone, but need to dissipate heat from multiple heat sources in the system at the same time. Not only high heat dissipation requirements need to be met, but also the temperature consistency of each device needs to be maintained. This requires a reasonable scheme to integrate the microchannel heat sinks in the system. In recent years, the research on microelectronic systems has mainly focused on single heat sources, optimizing and improving the structure of a single microchannel heat sink to enhance heat transfer, while there is less research on the integrated system of multiple microchannel heat sinks. To ensure good heat dissipation of the system when multiple heat sources exist, it is necessary to integrate microchannel systems with good heat dissipation performance and dissipate heat from multiple heat sources at the same time to ensure the stable working performance of the system. Summary of the Invention

[0004] The object of the present invention is to provide a microchannel heat dissipation integrated system for an array heat source with low thermal resistance and low pumping power, so that when there are multiple arrays of heat dissipation elements, the system integrating multiple microchannel regions can be efficiently cooled, and the temperature distribution among the elements can be ensured to be uniform. In the system device designed by the present invention, each microchannel region adopts a "two-in and three-out" flow mode, dividing a section of the microchannel into four segments, reducing the fluid flow length, effectively suppressing the accumulation of heat at the flow end, reducing the occurrence of "hot spots", and reducing the internal thermal resistance of the system; at the same time, due to the shorter flow length, the fluid velocity decreases at a certain flow rate, the pressure drop in the system decreases accordingly, and the pumping power consumed by the external pipeline decreases. The system adopts a symmetric design, enabling uniform flow rate distribution into each heat dissipation region. The better the fluid distribution uniformity, the more similar the heat dissipation performance of each heat dissipation region, and the more it can ensure the temperature consistency among the heat dissipation elements, providing a reliable temperature environment for the stable operation of electronic devices.

[0005] The present invention designs a microchannel heat dissipation integrated system for an array heat source with low thermal resistance and low pumping power, as Figure 1 shown. To further clarify the system structure, Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 、 Figure 7 、 Figure 8 、 Figure 9 、 Figure 10 、 Figure 11 、 Figure 12 、 Figure 13 and Figure 14 are respectively the front exploded view of the overall structure of the system, the back exploded view of the overall structure of the system, the top view of the flow distribution plate, the bottom view of the flow distribution plate, the axonometric view of the top plate, the axonometric view of the bottom plate, the front view of the system, the sectional view taken along A-A, the sectional view taken along B-B, the sectional view taken along C-C, the sectional view taken along D-D, the sectional view taken along E-E, and the schematic diagram of the H-shaped flow distribution channel branch structure.

[0006] The present invention designs a microchannel heat dissipation integration system for an array heat source with low thermal resistance and low pump power, which is characterized in that it includes a top plate (1), a flow dividing plate (2) and a bottom plate (3) that are stacked and packaged together in sequence; on the back surface of the flow dividing plate (2), that is, the surface that fits with the bottom plate (3), a fluid inlet (4) for an external pipeline and a liquid inlet flow dividing channel (6) are processed. The liquid inlet flow dividing channel (6) is located on one side of the back surface of the flow dividing plate (2), and the length direction of the liquid inlet flow dividing channel (6) is parallel to the length direction of the flow dividing plate (2); a fluid inlet (4) is led out from the middle position in the length direction of the liquid inlet flow dividing channel (6), and the fluid inlet (4) communicates with the outside from the side surface of the flow dividing plate (2); both ends of the liquid inlet flow dividing channel (6) are respectively connected to an intermediate connecting channel in each of one first-level H-shaped flow dividing channel branch (13) through a channel parallel to the width direction of the flow dividing plate (2), and there are two first-level H-shaped flow dividing channel branches (13) in total; the intermediate connecting channel in the first-level H-shaped flow dividing channel branch (13) is parallel to the length direction of the flow dividing plate (2); the four end parts of each first-level H-shaped flow dividing channel branch (13) are respectively connected to an intermediate connecting channel in each of one second-level H-shaped flow dividing channel branch (14) through a channel parallel to the length direction of the flow dividing plate (2), and there are 8 second-level H-shaped flow dividing channel branches (14) in total. The intermediate connecting channel in each second-level H-shaped flow dividing channel branch (14) is parallel to the width direction of the flow dividing plate (2); the four end parts of each second-level H-shaped flow dividing channel branch (14) are respectively connected to one end channel (15) parallel to the width direction of the flow dividing plate (2), and a liquid injection hole (8) is provided at the middle position of the end channel (15), and there are 32 liquid injection holes (8) in total. Each liquid injection hole (8) penetrates through the thickness of the flow dividing plate (2) to reach the front surface of the flow dividing plate (2).

[0007] On the front side of the flow splitter plate (2), i.e., the side that fits against the top plate (1), several microchannel regions (9) are machined. One microchannel region (9) corresponds to one heat source (11) on the top plate (1), and multiple heat sources (11) arranged in an array correspond to multiple microchannel regions (9) arranged in an array. The direction of the microchannels within each microchannel region (9) is parallel to the length direction of the flow splitter plate (2), such that the flow direction of the liquid within the microchannels is parallel to the length direction of the flow splitter plate (2). At the middle and both ends of each microchannel region (9) in the microchannel direction, confluence channel branches (12) are provided respectively. The length direction of the confluence channel branches (12) is parallel to the width direction of the flow splitter plate (2). An independent liquid storage area channel (10) is provided in the middle of the microchannel region between adjacent confluence channel branches (12) within the same microchannel region (9). The length direction of the liquid storage area channel (10) is parallel to the length direction of the confluence channel branches (12). A liquid injection hole (8) corresponds to the middle of each liquid storage area channel (10). Each secondary H-shaped flow splitter channel branch (14) corresponds to two microchannel regions (9). All the confluence channel branches (12) are connected to a liquid collecting channel (16). The length direction of the liquid collecting channel (16) is parallel to the length direction of the flow splitter plate (2). The two ends of the liquid outlet confluence channel (7) parallel to the liquid collecting channel (16) are connected to the liquid collecting channel (16). A fluid outlet (5) is provided in the middle of the liquid outlet confluence channel (7). The fluid outlet (5) communicates with the outside through the side surface of the flow splitter plate (2). The fluid outlet (5) and the fluid inlet (4) communicate with the outside through two opposite side surfaces of the flow splitter plate (2) respectively.

[0008] The front side structure of the flow splitter plate (2) is symmetrically distributed along the center line in the middle width direction; the back side structure of the flow splitter plate (2) is symmetrically distributed along the center line in the middle width direction.

[0009] The top plate (1), the flow splitter plate (2) and the bottom plate (3) are welded together by vacuum brazing to form a closed fluid flow system.

[0010] The processing methods of the liquid injection hole (8), the inlet flow splitter channel (6), the liquid outlet confluence channel (7) and the microchannels (9) are not limited. Various additive manufacturing techniques or cutting techniques can be used for processing, and it is required to ensure relatively good processing accuracy as much as possible. The shapes of all the channels are rectangular, and the shapes of all the holes are circular.

[0011] The flow route of the cooling medium is as follows: the cooling medium flows into the system from the fluid inlet (4), is diverted once through the T-type total diversion channel (6), and then the two streams of fluid continue to divert through the first-level H-type diversion channel and the second-level H-type diversion channel respectively, and are finally divided into 32 streams of fluid, each of which flows into each liquid storage area channel (10) through each injection hole (8); the microchannel (9) area covered by each heat source (11) adopts a "two-in-three-out" structure, that is, the fluid enters from the two liquid storage areas (10) and flows out from the three confluence channel branches (12); finally, it converges at the fluid total outlet (5) through the total confluence channel (7) and flows out of the system.

[0012] In order to avoid the accumulation of flow in each part of the channel affecting the uniformity of flow distribution, the depth and width of each channel should be adjusted based on the principle of ensuring that the cross-sectional area of each part of the channel is as equal as possible.

[0013] The cooling medium can be water, and the solid material can be a metal material with a large thermal conductivity, such as aluminum.

[0014] The present invention has the following advantages and effects:

[0015] 1. Through the "two inlet and three outlet" structure, a microchannel is divided into four sections, which reduces the flow channel length, maximizes the use of the inlet section effect, effectively enhances heat transfer, and reduces the thermal resistance of the system. Because the fluid flow length is shortened, the flow velocity is reduced at a given flow rate, and the system pump work is reduced accordingly.

[0016] 2. Each channel and branch is completely symmetrical, ensuring that the system device has good flow distribution uniformity, so that the surface temperature of each heat source is evenly distributed, and the system has high temperature control accuracy.

[0017] 3. Various grooves and microchannels are directly processed on the manifold, and the top plate and bottom plate are welded to the manifold through vacuum brazing technology to ensure the sealing of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 : A three-dimensional schematic diagram of the overall structure of the present invention;

[0019] Figure 2 : A schematic diagram of an exploded front view of the overall structure of the present invention;

[0020] Figure 3 : Schematic diagram of the back explosion of the overall structure of the present invention;

[0021] Figure 4 : A top view of the diverter plate of the present invention;

[0022] Figure 5 : Bottom view of the diverter plate of the present invention;

[0023] Figure 6: Axonometric view of the top plate of the present invention;

[0024] Figure 7 : Axonometric view of the bottom plate of the present invention;

[0025] Figure 8 : Front view of the present invention;

[0026] Figure 9 : A-A sectional view of the present invention;

[0027] Figure 10 : B-B sectional view of the present invention;

[0028] Figure 11 : C-C sectional view of the present invention;

[0029] Figure 12 : D-D sectional view of the present invention;

[0030] Figure 13 : E-E sectional view of the present invention;

[0031] Figure 14 : Schematic diagram of the H-shaped flow splitting channel branch structure;

[0032] Wherein: 1 - top plate, 2 - flow splitting plate, 3 - bottom plate, 4 - fluid inlet, 5 - fluid outlet, 6 - liquid inlet flow splitting channel, 7 - liquid outlet confluence channel, 8 - liquid injection hole, 9 - microchannel, 10 - liquid storage area channel, 11 - heat source; 12 - confluence channel branch, 13 - primary H-shaped flow splitting channel branch, 14 - secondary H-shaped flow splitting channel branch, 15 - end channel, 16 - liquid collecting channel. Specific implementation method

[0033] The present invention will be further described below with reference to the accompanying drawings, but the present invention is not limited to the following embodiments. In the drawings, components with the same structure are denoted by the same numerical reference signs, and parts with similar functions are not repeated. The dimensions of each component shown in the drawings are arbitrarily shown, and the present invention does not limit the dimensions of each component.

[0034] Such as Figure 1 、 Figure 2 And Figure 3As shown, it comprises a top plate (1), a diverter plate (2) and a bottom plate (3) which are stacked and packaged together in sequence; the back of the diverter plate is processed with a fluid inlet (4) of an external pipeline and a liquid inlet diverter channel (6); the liquid inlet diverter channel (6) is divided into a T-shaped main diverter channel and several H-shaped diverter channel branches, and all the diverter channel branches are symmetrically distributed along the center line of the diverter plate; a circular through hole is provided at the bottom of the channel at the end of each branch, which is recorded as a liquid injection hole (8) for the fluid to flow into the liquid storage area channel (10) on the front of the diverter plate; the diverter plate (2) Several microchannels (9) are processed on the front side. The coverage area of the microchannels (9) corresponds to multiple heat sources (11) arranged in an array. Two liquid storage area channels (10) mentioned above are arranged at equal distances in the middle of the microchannels (9) in each heat source area to separate the microchannels; and confluence channel branches for the fluid outflow system are processed at both ends of the microchannels and the center of the flow channel. Several confluence channel branches and a T-shaped total confluence channel constitute a liquid outlet confluence channel (7) for the fluid to flow out of the system through a fluid outlet (5) connected to an external pipeline.

[0035] The injection hole (8) at the end of each branch channel on the back of the diverter plate (2) is located at the center of the branch channel to achieve the purpose of bilateral symmetry, and is connected to the liquid storage area channel (10) on the front of the diverter plate (2), ensuring that the fluid can flow into the liquid storage area channel (10) on the front of the diverter plate (2) through the injection hole (8) and into the microchannel (9); the top plate (1), the diverter plate (2) and the bottom plate (3) are welded together by vacuum brazing to form a closed fluid flow system.

[0036] Example 1:

[0037] In the case of multiple heat source arrays, a microchannel heat dissipation integrated system with low thermal resistance and low pump work is designed. The device connects the various structures through welding technology. The specific structure is as follows Figure 1 As shown in the figure, the device is made of aluminum alloy, and the cooling medium is water. Simulated heat sources are placed on the top plate, with a total of 16 heat sources arranged in an array, covering each microchannel area. Heating output is regulated by controlling the voltage of an external circuit. A constant-temperature water tank provides sufficient inlet flow to the system and maintains the fluid inlet temperature at room temperature.

[0038] After the fluid flows into the system from the fluid inlet, it passes through the first T-shaped channel, and the fluid is evenly divided into two streams. Then, each stream flows into several H-shaped channels and is evenly divided into 32 fluid streams. After that, each fluid stream flows into the liquid storage tank on the back of the flow distribution plate through the liquid injection holes, and then flows to both ends of the microchannel respectively. Finally, the fluid is combined through several confluence channels and flows out of the system through the fluid outlet. Because the system adopts the principle of strict symmetry, during the entire flow process, each flow rate distribution is relatively uniform. In order to prevent fluid accumulation at the outlet, the depth of the confluence channels can be gradually increased along the flow direction, which maximally ensures the fluid distribution uniformity of the system and enhances the temperature uniformity of the heat dissipation element. Also, because each part of the microchannel is divided into four flow channels, the heat accumulation at the end of the flow channel is inhibited, preventing the formation of hot spots and further strengthening the heat transfer. To a certain extent, the working stability of the heat dissipation element is improved and the service life is extended.

[0039] The above description is only a preferred embodiment of the method of the present invention and is not used to limit the method of the present invention. During the actual implementation process, according to the depth and width of the liquid inlet flow distribution channels and the liquid outlet confluence channels on the flow distribution plate, the size and aspect ratio of the microchannels, and the shape and size of the liquid storage area channels, the system can obtain different heat transfer effects. The processing method, the types of cooling working fluids and solid materials, and the application environment of the present device may all be changed or replaced, but the above-mentioned forms of changes will not fundamentally change the method of the present invention. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field of the present invention based on the concept of the present invention through logical analysis, reasoning, or limited experiments should be within the protection scope determined by the claims.

Claims

1. A microchannel heat dissipation integrated system for an array heat source with low thermal resistance and low pumping power, characterized in that: It includes a top plate (1), a flow splitting plate (2) and a bottom plate (3) which are successively stacked and encapsulated together; on the back surface of the flow splitting plate (2), i.e., the surface that fits the bottom plate (3), a fluid inlet (4) for an external pipeline and a liquid inlet flow splitting channel (6) are machined. The liquid inlet flow splitting channel (6) is located on one side of the back surface of the flow splitting plate (2), and the length direction of the liquid inlet flow splitting channel (6) is parallel to the length direction of the flow splitting plate (2); at the middle position in the length direction of the liquid inlet flow splitting channel (6), the fluid inlet (4) is led out, and the fluid inlet (4) communicates with the outside from the side surface of the flow splitting plate (2); both ends of the liquid inlet flow splitting channel (6) are respectively communicated with an intermediate connecting channel in each of one first-stage H-shaped flow splitting channel branch (13) through a channel parallel to the width direction of the flow splitting plate (2), and there are two first-stage H-shaped flow splitting channel branches (13) in total; the intermediate connecting channel in the first-stage H-shaped flow splitting channel branch (13) is parallel to the length direction of the flow splitting plate (2); each of the four end parts of each first-stage H-shaped flow splitting channel branch (13) is respectively communicated with an intermediate connecting channel in a second-stage H-shaped flow splitting channel branch (14) through a channel parallel to the length direction of the flow splitting plate (2), and there are 8 second-stage H-shaped flow splitting channel branches (14) in total. The intermediate connecting channel in each second-stage H-shaped flow splitting channel branch (14) is parallel to the width direction of the flow splitting plate (2); each of the four end parts of each second-stage H-shaped flow splitting channel branch (14) is respectively communicated with an end channel (15) parallel to the width direction of the flow splitting plate (2), and a liquid injection hole (8) is provided at the middle position of the end channel (15). There are 32 liquid injection holes (8) in total, and each liquid injection hole (8) penetrates through the thickness of the flow splitting plate (2) to reach the front surface of the flow splitting plate (2); On the front side of the flow splitter plate (2), i.e., the side that fits against the top plate (1), several microchannel regions (9) are machined. One microchannel region (9) corresponds to one heat source (11) on the top plate (1), and multiple heat sources (11) arranged in an array correspond to multiple microchannel regions (9) arranged in an array. The direction of the microchannels within each microchannel region (9) is parallel to the length direction of the flow splitter plate (2), such that the flow direction of the liquid within the microchannels is parallel to the length direction of the flow splitter plate (2). At the middle and both ends of each microchannel region (9) in the microchannel direction, confluence channel branches (12) are provided respectively. The length direction of the confluence channel branches (12) is parallel to the width direction of the flow splitter plate (2). An independent liquid storage area channel (10) is provided in the middle of the microchannel region between adjacent confluence channel branches (12) within the same microchannel region (9). The length direction of the liquid storage area channel (10) is parallel to the length direction of the confluence channel branches (12). A liquid injection hole (8) corresponds to the middle of each liquid storage area channel (10). Each secondary H-shaped flow splitter channel branch (14) corresponds to two microchannel regions (9). All the confluence channel branches (12) are connected to a liquid collecting channel (16). The length direction of the liquid collecting channel (16) is parallel to the length direction of the flow splitter plate (2). The two ends of the liquid outlet confluence channel (7) parallel to the liquid collecting channel (16) are connected to the liquid collecting channel (16). A fluid outlet (5) is provided in the middle of the liquid outlet confluence channel (7). The fluid outlet (5) communicates with the outside through the side surface of the flow splitter plate (2). The fluid outlet (5) and the fluid inlet (4) communicate with the outside through two opposite side surfaces of the flow splitter plate (2) respectively.

2. The microchannel heat dissipation integrated system of an array heat source with low thermal resistance and low pump power according to claim 1, characterized in that: The front side structure of the flow splitter plate (2) is symmetrically distributed along the center line in the middle width direction; the back side structure of the flow splitter plate (2) is symmetrically distributed along the center line in the middle width direction.

3. The microchannel heat dissipation integrated system of an array heat source with low thermal resistance and low pump power according to claim 1, characterized in that: The top plate (1), the flow splitter plate (2) and the bottom plate (3) are welded together by vacuum brazing to form a closed fluid flow system.

4. The microchannel heat dissipation integration system of an array heat source with low thermal resistance and low pump power according to claim 1, characterized in that: All the channel shapes are rectangular, and all the hole shapes are circular.

5. The microchannel heat dissipation integrated system of an array heat source with low thermal resistance and low pump power according to claim 1, characterized in that: The flow path of the cooling working medium is as follows: The cooling working medium flows into the system from the fluid inlet (4), undergoes a first-stage splitting through the inlet flow splitter channel (6), and then the two streams of fluid are further split respectively through the primary H-shaped flow splitter channel branches and the secondary H-shaped flow splitter channel branches, and finally are split into 32 streams of fluid. Each stream of fluid flows into each liquid storage area channel (10) through each liquid injection hole (8). Each microchannel region (9) covered by each heat source (11) adopts a "two-in three-out" structure, that is, the fluid enters from two liquid storage area channels (10) and flows out from three confluence channel branches (12). Finally, it converges at the fluid outlet (5) through the liquid outlet confluence channel (7) and flows out of the system.

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