Heat dissipation unit, heat dissipation device and electronic device

Abstract

The invention relates to a heat dissipation unit, a heat dissipation device and an electronic device. The heat dissipation unit comprises a first flow channel layer and a second flow channel layer. The first flow channel layer comprises a first flow channel, a second flow channel and a first micro-flow channel, the first micro-flow channel comprises an inlet micro-flow channel and an outlet micro-flow channel which are parallel to each other, the first flow channel is communicated with the inlet micro-flow channel, and the second flow channel is communicated with the outlet micro-flow channel; the second flow channel layer comprises a second micro-flow channel, the inlet micro-flow channel and the second micro-flow channel are not parallel to each other and are communicated with each other, and the outlet micro-flow channel and the second micro-flow channel are not parallel to each other and are communicated with each other. Through the multi-layer heat dissipation flow channel structure, the heat dissipation effect and the temperature uniformity are improved.

Description

Technical Field

[0001] The present application relates to the technical field of heat dissipation, and particularly to a heat dissipation unit, a heat dissipation device and an electronic device. Background Art

[0002] At present, the high-density integration of chips and various electronic circuits has led to an increase in the heat flux density of components, and the resulting heat dissipation problems have become increasingly serious. At the present stage, the main heat dissipation methods for electronic devices are air-cooled heat dissipation, liquid-cooled heat dissipation and heat pipe heat dissipation. Although air-cooled heat dissipation has a simple structure, it is only effective for dissipating heat from low-power devices. During forced heat dissipation, a fan is used to increase air flow to carry away heat, which is likely to generate vibration and noise. Therefore, the heat dissipation capacity of the air-cooled heat dissipation method is limited and cannot meet the heat dissipation requirements of high-density integrated chips and electronic circuits. Liquid-cooled heat dissipation uses a liquid coolant to directly contact with electronic components to carry away heat, and can be applied to devices with a relatively high heat flux density. However, the liquid-cooled heat dissipation device has a certain size and occupies a large space, which is not conducive to the development of components towards miniaturization. The heat dissipation capacity of heat pipe heat dissipation is excellent, and a large amount of heat can be transferred under a small temperature difference. However, there is a heat transfer limit for heat pipes. When the heat generation of high-power high-density integrated devices exceeds the limit value that the heat pipe can withstand, the heat pipe will fail and cannot be used continuously. Summary of the Invention

[0003] In view of the above technical problems, the present application provides a heat dissipation unit, a heat dissipation device and an electronic device, which improve the heat dissipation effect and temperature uniformity.

[0004] To solve the above technical problems, in a first aspect, the present application provides a heat dissipation unit, including a first flow channel layer and a second flow channel layer;

[0005] The first flow channel layer includes a first flow channel, a second flow channel and a first micro-channel. The first micro-channel includes an inlet micro-channel and an outlet micro-channel that are parallel to each other. The first flow channel is communicated with the inlet micro-channel, and the second flow channel is communicated with the outlet micro-channel;

[0006] The second flow channel layer includes a second micro-channel. The inlet micro-channel and the second micro-channel are not parallel to each other and are mutually penetrated, and the outlet micro-channel and the second micro-channel are not parallel to each other and are mutually penetrated.

[0007] In an embodiment, the first micro-channel includes a plurality of inlet micro-channels and a plurality of outlet micro-channels with equal numbers, and the plurality of inlet micro-channels and the plurality of outlet micro-channels are arranged alternately.

[0008] In an embodiment, the width of the first micro-channel is smaller than the width of the first flow channel, and the width of the first micro-channel is smaller than the width of the second flow channel.

[0009] In one embodiment, the second flow channel layer includes a plurality of second microchannels arranged in parallel, and the second microchannels are perpendicular to the first microchannels.

[0010] In one embodiment, the first flow channel layer and the second flow channel layer are attached to each other.

[0011] In one embodiment, the first microchannel is formed by attaching a continuous and meandering wall portion to the second flow channel layer.

[0012] In one embodiment, the second microchannel includes a plurality of parallel grooves, the openings of the grooves face the wall portion, and the opening sides of the grooves are attached to the wall portion.

[0013] In a second aspect, the present application further provides a heat dissipation device, including a plurality of heat dissipation units as described in the first aspect.

[0014] In one embodiment, the first flow channels of the plurality of heat dissipation units are connected to each other to form a fluid inlet of the heat dissipation device, and the second flow channels of the plurality of heat dissipation units are connected to each other to form a fluid outlet of the heat dissipation device.

[0015] In a third aspect, the present application further provides an electronic device, including the heat dissipation unit as described in the first aspect, and / or the heat dissipation device as described in the second aspect.

[0016] The heat dissipation unit, heat dissipation device and electronic device of the present application, the heat dissipation unit includes a first flow channel layer and a second flow channel layer; the first flow channel layer includes a first flow channel, a second flow channel and a first microchannel, the first microchannel includes an inlet microchannel and an outlet microchannel that are parallel to each other, the first flow channel is connected to the inlet microchannel, and the second flow channel is connected to the outlet microchannel; the second flow channel layer includes a second microchannel, the inlet microchannel and the second microchannel are not parallel to each other and communicate with each other, and the outlet microchannel and the second microchannel are not parallel to each other and communicate with each other. The present application improves the heat dissipation effect and temperature uniformity through a multi-level heat dissipation flow channel structure. Description of the Drawings

[0017] Figure 1 is a schematic structural diagram of a heat dissipation unit shown according to an embodiment of the present application;

[0018] Figure 2 is a schematic structural diagram of a first flow channel layer shown according to an embodiment of the present application;

[0019] Figure 3 is a schematic structural diagram of a second flow channel layer shown according to an embodiment of the present application;

[0020] Figure 4 is a schematic structural diagram of a heat dissipation device shown according to an embodiment of the present application;

[0021] Figure 5 It is a schematic diagram of the connection structure of multiple first flow channel layers in the heat dissipation device shown according to the embodiments of the present application;

[0022] Figure 6 It is a schematic diagram of the connection structure of multiple second flow channel layers in the heat dissipation device shown according to the embodiments of the present application.

[0023] Explanation of reference numerals: 1 - heat dissipation unit; 10 - first flow channel layer; 11 - first flow channel; 12 - second flow channel; 13 - first micro flow channel; 131 - inlet micro flow channel; 132 - outlet micro flow channel; 20 - second flow channel layer; 21 - second micro flow channel. Detailed implementation manners

[0024] The following specific embodiments illustrate the implementation manners of the present application. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification.

[0025] In the following description, reference is made to the accompanying drawings, which describe several embodiments of the present application. It should be understood that other embodiments may also be used, and mechanical composition, structure, electrical, and operational changes may be made without departing from the spirit and scope of the present application. The following detailed description should not be considered restrictive. The terms used herein are only for describing specific embodiments and are not intended to limit the present application.

[0026] Although in some instances the terms first, second, etc. are used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

[0027] Furthermore, as used herein, the singular forms "a", "an", and "the" are also intended to include the plural forms unless the context indicates otherwise. It should be further understood that the terms "comprising", "including" indicate the presence of the described features, steps, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or meaning any one or any combination. Thus, "A, B, or C" or "A, B, and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A, B, and C". An exception to this definition occurs only when the combination of elements, functions, steps, or operations is inherently mutually exclusive in some way.

[0028] Microchannel heat dissipation is to design and manufacture microchannels inside a substrate. Through the flow of microfluids in the microchannels, the heat generated during the operation of electronic devices is taken away to achieve the purpose of heat dissipation. Among the related patents on microchannel structure design, it has more emphasis and applicability in the field. Among the related patents on microchannel heat dissipation, to improve the heat dissipation efficiency of the microchannel, more contact area between the microchannel and the electronic device is pursued. However, most microchannel designs fail to effectively take into account heat dissipation, temperature uniformity, and the scalability of the microchannel at the same time.

[0029] Since microchannel heat dissipation has a high heat dissipation capacity compared with other heat dissipation methods, it can significantly improve the heat dissipation efficiency. To solve the problems of the existing technology, an embodiment of the present invention proposes a heat dissipation unit, including a multi-level heat dissipation channel structure based on fractal, which can improve the heat dissipation effect and temperature uniformity, enabling the microchannel to expand in the three-dimensional space and expand the area on the plane when the processing ability is satisfied. Figure 1 It is a schematic structural diagram of the heat dissipation unit shown according to the embodiment of the present application. As Figure 1 shown, the heat dissipation unit of the embodiment of the present application includes a first channel layer 10 and a second channel layer 20; the first channel layer 10 includes a first channel 11, a second channel 12, and a first microchannel 13. The first microchannel 13 includes an inlet microchannel 131 and an outlet microchannel 132 that are parallel to each other. The first channel 11 is connected to the inlet microchannel 131, and the second channel 12 is connected to the outlet microchannel 132; the second channel layer 20 includes a second microchannel 21. The inlet microchannel 131 and the second microchannel 21 are not parallel to each other and are mutually penetrated, and the outlet microchannel 132 and the second microchannel 21 are not parallel to each other and are mutually penetrated.

[0030] Here, the heat dissipation unit includes a multi-level heat dissipation channel structure composed of the first channel layer 10 and the second channel layer 20. The microchannels in the first channel layer 10 and the microchannels in the second channel layer 20 can penetrate each other, so that the cooling medium entering from the first channel 11 passes through the inlet microchannel 131, the second microchannel 21, the outlet microchannel 132 in sequence, and then flows out from the second channel 12, thus achieving the effect of heat dissipation and temperature reduction. The channel structure design of the heat dissipation unit is bionically referenced to the blood circulation system, avoiding the situation where the temperature distribution of each heat source shows a low temperature near the inlet and a high temperature at the outlet, and enabling better temperature uniformity on the surface of the heat source. Moreover, due to the existence of the second microchannel 21, the heat dissipation capacity of the heat dissipation unit is greatly increased, and the heat dissipation efficiency is improved. In addition, since the heat dissipation unit presents an assembled structure with channel hierarchy, it is convenient for customized assembly and expansion of various heat source distribution situations, and whether to manufacture the second channel layer 20 can be selected according to the heat source distribution situation, taking into account both heat dissipation performance and processing cost.

[0031] The heat dissipation unit further includes a cover plate (not shown in the figure), and the cover plate is hermetically connected to the first flow channel layer 10 to ensure that the cooling medium in the heat dissipation unit does not leak.

[0032] In one embodiment, the first micro-channel 13 includes a plurality of inlet micro-channels 131 and a plurality of outlet micro-channels 132 with equal numbers, and the plurality of inlet micro-channels 131 and the plurality of outlet micro-channels 132 are arranged alternately.

[0033] As Figure 2 shown, since the first flow channel 11 is communicated with the inlet micro-channel 131, and the second flow channel 12 is communicated with the outlet micro-channel 132, the plurality of inlet micro-channels 131 and the plurality of outlet micro-channels 132 which are alternately and evenly distributed enable the cooling medium to be evenly distributed in the first flow channel layer, and can improve the temperature uniformity in the heat dissipation unit.

[0034] In one embodiment, the width of the first micro-channel 13 is smaller than the width of the first flow channel 11, and, the width of the first micro-channel 13 is smaller than the width of the second flow channel 12.

[0035] Fractal design is a design concept based on the principle of fractal geometry, which usually involves continuously dividing a pattern or structure into smaller and smaller parts while maintaining the overall proportion and shape. The flow channels in the first flow channel layer are based on fractal design, and are connected by a plurality of narrower first micro-channels 13 between the first flow channel 11 and the second flow channel 12, enabling the first micro-channel 13 to arbitrarily expand the area on the plane when the processing capacity is satisfied, improving the heat dissipation effect and temperature uniformity.

[0036] In one embodiment, the second flow channel layer 20 includes a plurality of second micro-channels 21 arranged in parallel, and the second micro-channels 21 are perpendicular to the first micro-channels 13.

[0037] The second flow channel layer 20 is composed of a plurality of second micro-channels 21. The first micro-channels 13 in the first flow channel layer 10 are perpendicularly connected to the second micro-channels 21 in the second flow channel layer 20 and are mutually communicated at the connection. The cooling medium flows in through the large flow channel of the first flow channel 10 at the inlet, is shunted to the inlet micro-channels 131 of the first flow channel layer 10, and the cooling medium flowing through the inlet micro-channels 131 flows into the second micro-channels 21 of the second flow channel layer 20 through the through connection between the inlet micro-channels 131 and the second micro-channels 21, and then passes through the outlet micro-channels 132 of the first flow channel layer 10 and converges into the large flow channel of the second flow channel 12 at the outlet to achieve the purpose of heat dissipation. The design that the second micro-channels 21 are perpendicular to the first micro-channels 13 enables the flow direction of the cooling medium in the second flow channel layer 20 to be consistent with that in the first flow channel layer 10, ensuring that the cooling medium is evenly distributed in the heat dissipation unit.

[0038] In one embodiment, the first flow channel layer 10 and the second flow channel layer 20 are attached to each other. In this way, the path for the cooling medium to enter the second flow channel layer 20 from the first flow channel layer 10 can be shortened, the flow rate of the cooling medium in the heat dissipation unit can be accelerated, and the heat dissipation efficiency can be improved.

[0039] In one embodiment, the first micro-channel 13 is formed by attaching a continuous and meandering wall portion to the second flow channel layer 20.

[0040] The first micro-channel 13 is formed by repeatedly bending and extending a continuous wall portion in a snake shape. Each bend of the continuous wall portion forms the end point of an inlet micro-channel 131 or an outlet micro-channel 132, and the opening between every two bends of the continuous wall portion forms the starting point of an inlet micro-channel 131 or an outlet micro-channel 132. In this way, a plurality of inlet micro-channels 131 and a plurality of outlet micro-channels 132 with equal numbers can be formed, and the plurality of inlet micro-channels 131 and the plurality of outlet micro-channels 132 are arranged alternately. Such a process design is simple, the processing difficulty is low, and the shape difference of the prepared flow channels is small and the precision is high.

[0041] In one embodiment, the second micro-channel 21 includes a plurality of parallel grooves, the openings of the grooves face the wall portion, and the opening sides of the grooves are attached to the wall portion.

[0042] As Figure 3 shown, by opening a plurality of grooves with equal length and width, equal spacing and parallel on a substrate, the second micro-channel 21 can be formed, and the processing is simple and convenient. The openings of the grooves face the continuous wall portion for forming the first micro-channel 13, and the opening sides of the grooves are attached to the wall portion, so that the first micro-channel 13 is formed in the attachment area between the wall portion and the substrate. At the same time, in the non-attachment area between the wall portion and the substrate, the first micro-channel 13 and the second micro-channel 21 can be connected through.

[0043] In one embodiment, the first flow channel layer 10 and the second flow channel layer 20 are connected by welding. Preferably, diffusion welding can be used to connect the first flow channel layer 10 and the second flow channel layer 20. It should be noted that diffusion welding is a welding method carried out in a vacuum or protective atmosphere environment, which uses high temperature and pressure to tightly press two workpieces to be welded together. First, the welding surfaces of the two workpieces to be welded are processed to be very flat and smooth, and then the two workpieces are closely attached. Then, the whole device is heated to a certain temperature and maintained for a period of time, so that the atoms and molecules between the contact surfaces can approach a distance where they can diffuse with each other. In this way, the mutual diffusion between atoms forms a metallurgical connection during the subsequent heating and holding process, thus realizing a firm joint.

[0044] In the process of fabricating the first microchannel 13 and / or the second microchannel 21, when the size of the microchannel is very small, processes such as photolithography and etching can be adopted; when the size of the microchannel is relatively large, traditional metal processing techniques can be used. The wall surface does not need to be smooth and can be porous and rough, thereby increasing the heat transfer capacity while reducing the processing difficulty. If the heat dissipation unit is formed by etching on the silicon cover plate, after the first flow channel layer 10 and the second flow channel layer 20 are etched respectively, the two layers can be joined together by methods such as diffusion welding to increase the structural mechanical strength and structural stability of the heat dissipation unit. In addition, the heat dissipation unit made of metal material can also connect the first flow channel layer 10 and the second flow channel layer by means of diffusion welding. If the heat dissipation unit is a multi-layer structure with micro-nano size, semiconductor processing techniques such as epitaxy introduction, etching, and photolithography can be adopted.

[0045] In one embodiment, the heat dissipation unit further includes a power source for conveying the cooling medium in the heat dissipation unit.

[0046] For the heat dissipation unit of the embodiment of the present application, since the flow directions of the cooling medium in the first flow channel layer 10 and the second flow channel layer 20 are consistent, only one power source is needed to complete the conveyance of the cooling medium, which reduces the burden of energy and the spatial design of external components. Specifically, when the cooling medium is liquid metal, an electromagnetic pump arranged at the outer outlet or inlet of the flow channel can be used as the power source. When the cooling medium is water, a combination of a water tank and a water pump can be used as the power source.

[0047] In one embodiment, the heat dissipation unit further includes a third flow channel layer, which is attached to the side of the second flow channel layer 20 away from the first flow channel layer 10.

[0048] Here, in order to further improve the heat dissipation efficiency of the heat dissipation unit, any number of third flow channel layers (not shown in the figure) can be extended in the space. The structure of the third flow channel layer is the same as that of the second flow channel layer 20. When arranging, the third microchannels of the third flow channel layer can be set to be parallel or non-parallel to the second microchannels 21.

[0049] For the heat dissipation unit of the embodiment of the present application, based on the fractal-based multi-level heat dissipation flow channel structure design, the cooling medium flows in from the large flow channel, disperses into the microchannels, and then is collected and flows out from the large flow channel, avoiding the situation of relying on the size of the micro pump in the general microchannel liquid cooling heat dissipation design. The structure of the microchannels adopts a layered design, and the cooling medium flows through the inlet microchannels 131 of the first flow channel layer 10, the second flow channel layer 20 in sequence, and then returns to the outlet microchannels 132 of the first flow channel layer 10, realizing heat transfer and homogenization, enabling better temperature uniformity on the surface of the heat source, increasing the heat dissipation capacity, and improving the heat dissipation efficiency.

[0050] The cross-section of the first microchannel 13 and / or the second microchannel 21 can be at least one of a quadrilateral, an arc shape, and a V shape, which is convenient for processing and customization, can achieve multi-scale compatibility, and takes into account heat dissipation performance and processing cost.

[0051] The heat dissipation unit of the present application includes a first flow channel layer and a second flow channel layer; the first flow channel layer includes a first flow channel, a second flow channel, and a first microchannel. The first microchannel includes an inlet microchannel and an outlet microchannel that are parallel to each other. The first flow channel is connected to the inlet microchannel, and the second flow channel is connected to the outlet microchannel; the second flow channel layer includes a second microchannel. The inlet microchannel and the second microchannel are not parallel to each other and are mutually penetrated, and the outlet microchannel and the second microchannel are not parallel to each other and are mutually penetrated. In the heat dissipation unit of the embodiment of the present application, through the multi-level heat dissipation flow channel structure, the heat dissipation effect and temperature uniformity are improved.

[0052] Second Embodiment

[0053] Figure 4 is a schematic structural diagram of the heat dissipation device shown according to the embodiment of the present application. As Figure 4 shown, the embodiment of the present application also proposes a heat dissipation device, which includes a plurality of heat dissipation units 1 as described in the first embodiment.

[0054] As Figure 5 shown, when a plurality of heat dissipation units are combined, the first flow channels of the first flow channel layer 10 are connected to each other to form a single fluid inlet of the heat dissipation device. After the cooling medium enters through the fluid inlet, it can flow into a plurality of first flow channel layers 10 evenly at the same time. At the same time, the second flow channels of a plurality of heat dissipation units are connected to form a fluid outlet of the heat dissipation device. After the cooling medium flows out through the second flow channels of each first flow channel layer 10, it can converge at the fluid outlet. The design of this flow channel structure avoids the situation where the temperature distribution of each heat source shows that the temperature is low near the fluid inlet and high at the fluid outlet, and the overall temperature distribution of the heat dissipation device is more uniform and reasonable.

[0055] As Figure 6 shown, when a plurality of heat dissipation units are combined, a plurality of second flow channel layers 20 are arranged side by side, and the second microchannels of each second flow channel layer 20 are distributed in parallel, which is convenient for combined processing.

[0056] For the specific structure and technical effects of the heat dissipation device in the embodiment of the present application, please refer to the first embodiment, and details will not be described herein again.

[0057] The heat dissipation device of the embodiment of the present application includes a plurality of heat dissipation units, and each heat dissipation unit includes a first flow channel layer and a second flow channel layer; the first flow channel layer includes a first flow channel, a second flow channel and a first micro-channel, the first micro-channel includes an inlet micro-channel and an outlet micro-channel that are parallel to each other, the first flow channel is communicated with the inlet micro-channel, and the second flow channel is communicated with the outlet micro-channel; the second flow channel layer includes a second micro-channel, the inlet micro-channel and the second micro-channel are not parallel to each other and are mutually penetrated, and the outlet micro-channel and the second micro-channel are not parallel to each other and are mutually penetrated. Thus, the heat dissipation device of the embodiment of the present application improves the heat dissipation effect and temperature uniformity through a multi-level heat dissipation flow channel structure.

[0058] The third embodiment

[0059] The embodiment of the present application further provides an electronic device, including the heat dissipation unit as in the first embodiment, and / or the heat dissipation device as described in the second embodiment. The heat-generating element / device in the electronic device is attached to one side of the first flow channel layer in the heat dissipation unit, and / or the heat-generating element / device is attached to one side of the first flow channel layer in the heat dissipation device, so as to achieve the effect of heat dissipation and temperature reduction through the heat dissipation unit and / or the heat dissipation device.

[0060] For the specific structures and technical effects of the heat dissipation unit and / or the heat dissipation device in the electronic device of the embodiment of the present application, please refer to the first embodiment and the second embodiment, which will not be elaborated here.

[0061] The above embodiments are only illustrative of the principles and effects of the present application, and are not used to limit the present application. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present application should still be covered by the claims of the present application.

Claims

1. A heat dissipation unit, characterized in that, it includes a first flow channel layer and a second flow channel layer; the first flow channel layer includes a first flow channel, a second flow channel and a first micro-channel. The first micro-channel includes an inlet micro-channel and an outlet micro-channel that are parallel to each other. The first flow channel is communicated with the inlet micro-channel, and the second flow channel is communicated with the outlet micro-channel; the second flow channel layer includes a second micro-channel. The inlet micro-channel and the second micro-channel are not parallel to each other and are mutually penetrated, and the outlet micro-channel and the second micro-channel are not parallel to each other and are mutually penetrated.

2. The heat dissipation unit according to claim 1, characterized in that, the first micro-channel includes a plurality of inlet micro-channels and a plurality of outlet micro-channels with equal numbers, and the plurality of inlet micro-channels and the plurality of outlet micro-channels are arranged alternately.

3. The heat dissipation unit according to claim 2, characterized in that, the width of the first micro-channel is smaller than the width of the first flow channel, and the width of the first micro-channel is smaller than the width of the second flow channel.

4. The heat dissipation unit according to claim 1, characterized in that, the second flow channel layer includes a plurality of second micro-channels arranged in parallel, and the second micro-channels are perpendicular to the first micro-channels.

5. The heat dissipation unit according to claim 1, characterized in that, the first flow channel layer and the second flow channel layer are mutually adhered.

6. The heat dissipation unit according to claim 5, characterized in that, the first micro-channel is formed by adhering a continuous and winding wall portion to the second flow channel layer.

7. The heat dissipation unit according to claim 6, characterized in that, the second micro-channel includes a plurality of parallel grooves, the openings of the grooves face the wall portion and the opening sides of the grooves are adhered to the wall portion.

8. A heat dissipation device, characterized in that, it includes a plurality of heat dissipation units according to any one of claims 1 to 7.

9. The heat dissipation device according to claim 8, characterized in that, the first flow channels of the plurality of heat dissipation units are communicated with each other to form a fluid inlet of the heat dissipation device, and the second flow channels of the plurality of heat dissipation units are communicated with each other to form a fluid outlet of the heat dissipation device.

10. An electronic device, characterized in that, it includes a heat dissipation unit according to any one of claims 1 to 7, and / or a heat dissipation device according to claim 8 or 9.

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