Heat dissipation device

Abstract

The utility model relates to the technical field of heat dissipation, particularly provides a heat dissipation device, and aims to solve the problem that the operation stability of a power device is affected due to inconsistent heating power of the surfaces of the two sides of the power device. In order to achieve the purpose, the heat dissipation device comprises an outer shell, a first heat dissipation piece and a second heat dissipation piece, a cavity used for containing a cooling working medium is formed in the outer shell, an inlet and an outlet which are communicated with the cavity are formed in the outer shell, and the outer shell is provided with a first side wall and a second side wall which are opposite to each other; and the heat conduction structure is arranged in the cavity, and the two ends of the heat conduction structure are connected with the first side wall and the second side wall correspondingly. According to the invention, the temperature distribution at the two sides of the heat dissipation device is more uniform, thereby improving the utilization rate of a cooling working medium, improving the cooling efficiency, reducing the junction temperature of the power device at one side with a large heating value, and improving the operation stability of the power device.

Description

Technical Field

[0001] This application relates to the technical field of heat dissipation, and specifically provides a heat dissipation device. Background Art

[0002] Currently, in the power electronics industry, the heat generation problem during the operation of power devices has always been highly concerned. The industry usually cools power devices by setting heat sinks on the surfaces of power devices to ensure that the operating temperature of power devices is within a controllable range.

[0003] However, for some power devices, the heat generation powers of their emitters and collectors are different, resulting in a large temperature difference between the two side surfaces of the power device. Therefore, when the heat sink is located between adjacent power devices, due to the inconsistent surface temperatures of the two power devices in contact with the heat sink, it will not only affect the utilization efficiency of the cooling working medium in the heat sink, but also affect the junction temperature of the power device on the side with a larger heat generation amount, thereby affecting the operating stability of the power device.

[0004] Correspondingly, a new heat dissipation solution is needed in this field to solve the above problems. Summary of the Utility Model

[0005] This application aims to solve the above technical problems, that is, to solve the problem of affecting the operating stability of power devices due to inconsistent heat generation powers on both side surfaces of power devices.

[0006] To this end, this application provides a heat dissipation device, which includes:

[0007] A housing body, inside which a cavity for accommodating a cooling working medium is formed. An inlet and an outlet communicating with the cavity are respectively provided on the housing body, and the housing body has opposite first side walls and second side walls; and

[0008] A heat conduction structure, which is arranged in the cavity, and both ends of the heat conduction structure are respectively connected to the first side wall and the second side wall.

[0009] In a technical solution adopting the above heat dissipation device, the heat conduction structure is a heat pipe.

[0010] In a technical solution adopting the above heat dissipation device, a plurality of the heat pipes are arranged in the cavity.

[0011] In a technical solution adopting the above heat dissipation device, the plurality of heat pipes are arranged in a linear array or a circumferential array.

[0012] In a technical solution adopting the above heat dissipation device, the arrangement density of the heat pipes gradually decreases from the center of the cavity to the periphery.

[0013] In a technical solution adopting the above heat dissipation device, the axis of the heat pipe is perpendicular to the first side wall and the second side wall.

[0014] In a technical solution adopting the above heat dissipation device, a first groove is formed on the first side wall, and one end of the heat pipe is located in the first groove; and / or

[0015] A second groove is formed on the second side wall, and the other end of the heat pipe is located in the second groove.

[0016] In a technical solution adopting the above heat dissipation device, the heat conduction structure further includes a first pipe body connected between the first side wall and the second side wall, and the heat pipe is located inside the first pipe body.

[0017] In a technical solution adopting the above heat dissipation device, the heat conduction structure includes a second pipe body and a phase change material filled in the second pipe body, and two ends of the second pipe body are respectively connected to the first side wall and the second side wall.

[0018] In a technical solution adopting the above heat dissipation device, the heat conduction structure is a heat conduction rod connected between the first side wall and the second side wall.

[0019] As above, in the case of adopting the above technical solution, by connecting a heat conduction structure between the first side wall and the second side wall of the outer casing, during the process that the cooling working medium flows through the cavity, the heat conduction structure can transfer the heat on the side with a larger heat generation amount to the side with a smaller heat generation amount, making the temperature distribution on both sides of the heat dissipation device more uniform, thereby improving the utilization rate of the cooling working medium, increasing the cooling efficiency, reducing the junction temperature of the power device on the side with a larger heat generation amount, and further improving the operating stability of the power device.

[0020] Further, in the present application, the arrangement mode of the heat conduction structure is set as a linear array or a circular array according to the structural form of the power device, or the arrangement mode of the heat conduction structure is set as a form with a dense middle and a sparse periphery according to the inherent characteristics of the heat dissipation device, so as to further improve the temperature uniformity on both sides of the heat dissipation device, increase the cooling efficiency, and ensure the operating stability of the power device. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The following describes the preferred embodiments of the present application with reference to the drawings, in which:

[0022] Figure 1 is a schematic diagram of the overall structure of a heat dissipation device according to an embodiment of the present application;

[0023] Figure 2 is a cross-sectional view of a heat dissipation device according to an embodiment of the present application;

[0024] Figure 3 is a cross-sectional view of a heat dissipation device according to an embodiment of the present application from another perspective;

[0025] Figure 4 is a cross-sectional view of a heat dissipation device according to another embodiment of the present application.

[0026] In the figure, the reference numerals refer to the following:

[0027] 1. Outer housing; 100. Cavity; 11. Inlet; 12. Outlet; 13. First side wall; 131. First groove; 14. Second side wall; 141. Second groove; 2. Heat conduction structure; 21. Heat pipe; 22. First pipe body. Detailed implementation manners

[0028] The preferred implementation manners of the present application will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these implementation manners are only used to explain the technical principle of the present application and are not used to limit the protection scope of the present application. Those skilled in the art can make adjustments according to needs to adapt to specific application scenarios.

[0029] It should be noted that in the description of the present application, the terms indicating directions or positional relationships such as "upper", "lower", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for convenience of description and does not indicate or imply that the relevant devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application. In addition, ordinal numbers such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0030] In addition, it should also be noted that in the description of the present application, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0031] In the power electronics industry, each functional unit of the same device or power system usually has many power devices. Each power device has an emitter and a collector. The emitter and collector of the power device respectively constitute two different surfaces of the power device. Generally, a heat sink is arranged between adjacent power devices, and the two side surfaces of the heat sink are respectively attached to the surfaces of adjacent power devices.

[0032] Then, since the heat generation powers of the surfaces of adjacent power devices in contact with the heat sink are different, it will cause more heat to be carried away by the part of the cooling working fluid in the heat sink close to the surface with a larger heat generation amount, while less heat is carried away by the part of the cooling working fluid close to the surface with a smaller heat generation amount. Thus, the utilization rate of the cooling working fluid will be reduced. That is to say, the part of the cooling working fluid close to the surface with a smaller heat generation amount is not fully utilized, which will lead to an increase in the junction temperature of the power device on the side with a larger heat generation amount, thereby affecting the stability of the power device.

[0033] Referring to the accompanying drawings, Figure 1 is a schematic diagram of the overall structure of a heat dissipation device according to an embodiment of the present application, Figure 2 is a cross-sectional view of the heat dissipation device from one perspective according to an embodiment of the present application, Figure 3 is a cross-sectional view of the heat dissipation device from another perspective. The heat dissipation device includes a housing 1 and a heat conduction structure 2 disposed inside the housing 1.

[0034] Referring to Figure 2 and Figure 3 , a cavity 100 for accommodating the cooling working fluid is formed inside the housing 1. An inlet 11 and an outlet 12 communicating with the cavity 100 are respectively provided on the housing 1. The cooling working fluid enters the cavity 100 through the inlet 11 and is discharged from the outlet 12 to realize the flow of the cooling working fluid.

[0035] In an embodiment of the present application, the housing 1 is a cubic structure. A plurality of inlets 11 and outlets 12 are provided, and each inlet 11 corresponds to each outlet 12 one by one. The housing 1 has a first side wall 13 and a second side wall 14 disposed opposite to each other, and the first side wall 13 and the second side wall 14 are parallel to each other. Among them, the first side wall 13 and the second side wall 14 are respectively used to be in contact with the heat generating surfaces of the power devices. In some implementation manners of the present application, the cooling working fluid can adopt a phase change working fluid to perform heat exchange by using the latent heat of phase change, which has a stronger heat exchange effect compared with specific heat heat exchange. Based on this, in order to ensure the smooth flow of the cooling working fluid and make it easier for the gaseous working fluid to be discharged from the heat dissipation device, in practical applications, the housing 1 can be arranged in a form with the inlet 11 at the bottom and the outlet 12 at the top, that is, "bottom-in and top-out". In addition, the sizes and numbers of the inlets 11 and outlets 12 of the heat dissipation device can be adaptively adjusted according to the heat generation power of the power device, and the present application does not limit this.

[0036] The heat conduction structure 2 is disposed in the cavity 100, and both ends of the heat conduction structure 2 are connected to the first side wall 13 and the second side wall 14 respectively.

[0037] In an embodiment of the present application, the heat conduction structure 2 is a heat pipe 21. The heat pipe 21 is generally composed of a pipe shell, a wick, and end caps. After evacuating the inside of the pipe to a negative pressure, an appropriate amount of working liquid is filled, so that the capillary porous material of the wick close to the inner wall of the pipe is filled with liquid and then sealed. One end of the pipe is the evaporation section, and the other end is the condensation section. When one end of the heat pipe 21 is heated, the liquid in the wick pipe evaporates and vaporizes, and the vapor flows to the other end under a small pressure difference to release heat and condense into a liquid. The liquid then flows back to the evaporation section along the porous material by capillary action. This cycle repeats, and the heat is transferred from one end of the heat pipe 21 to the other end. The above structural composition and working principle of the heat pipe 21 are conventional technologies in the art. Of course, the specific form of the heat pipe 21 is not limited to the above examples, and the present application will not elaborate too much here.

[0038] Taking the example that power devices are provided on both sides of the heat dissipation device, during the operation of a power equipment or system, for a certain heat dissipation device, its first side wall 13 and second side wall 14 are respectively attached to the power devices on both sides, so that the heat dissipation device cools the surfaces of the power devices on both sides respectively. Since the heat generation amounts of the power devices on both sides are different, at this time, the side where the power device with a larger heat generation amount is located corresponds to the evaporation section of the heat pipe 21, and the side where the power device with a smaller heat generation amount is located corresponds to the condensation section of the heat pipe 21. The heat pipe 21 can transfer the heat from the side with a larger heat generation amount to the side with a smaller heat generation amount, thereby improving the utilization rate of the cooling medium, increasing the cooling efficiency, reducing the junction temperature of the power device on the side with a larger heat generation amount, and further improving the operating stability of the power device.

[0039] In addition, the presence of the heat pipe 21 can also play a supporting role between the first side wall 13 and the second side wall 14 of the outer housing 1, thereby improving the overall structural strength of the heat dissipation device. Considering the structural strength, optionally, the axis of the heat pipe 21 can be perpendicular to the first side wall 13 and the second side wall 14. Further, considering the insufficient structural strength of the heat pipe 21 itself and the structural strength of the heat dissipation device, a first pipe body 22 can also be connected between the first side wall 13 and the second side wall 14, and the heat pipe 21 is respectively arranged inside the first pipe body 22. In this way, the first pipe body 22 plays a main supporting role, while the heat pipe 21 is mainly responsible for heat transfer.

[0040] To improve the temperature uniformity on both sides of the heat dissipation device, multiple heat pipes 21 are arranged in the cavity 100. And the multiple heat pipes 21 can be arranged in a linear array or a circular array in the cavity 100.

[0041] It should be noted that the arrangement of the heat pipes 21 can be adjusted adaptively according to the structural form of the power device. For example, when the structural form of the power device is circular, or its heat generating surface is a circular area, the heat pipes 21 can be arranged in a circumferential array. When the structural form of the power device is square, or its heat generating surface is a rectangular area, the heat pipes 21 can be arranged in a linear array. The present application does not make specific restrictions on this, and similar adjustments to the arrangement form of the heat pipes 21 are within the protection scope of the present application.

[0042] In an embodiment of the present application, the arrangement density of the heat pipes 21 gradually decreases from the center of the cavity 100 to the periphery, that is, the arrangement of the heat pipes 21 is in a form of dense in the middle and sparse around.

[0043] It should be understood that for the heat dissipation device, its size is generally larger than that of the power device. That is, the areas of the first side wall 13 and the second side wall 14 are usually larger than the area of the heat generating surface of the power device, so as to ensure that the entire heat generating surface of the power device can be cooled. However, the problem that follows is that there is a temperature difference between the contact area of the outer casing 1 and the power device and the peripheral area of the outer casing 1. Even more, the temperature in the central area of the contact area between the outer casing 1 and the power device is higher than the temperature in the peripheral area of the contact area. This is because the peripheral area of the heat dissipation device is in contact with the cooling working medium inside but not in contact with the heat generating part of the power device. The closer the heat dissipation device is to its central area, the relatively higher the temperature. Based on this, the present application arranges the heat pipes 21 in a form of dense in the middle and sparse around, which can further improve the temperature uniformity on both sides of the heat dissipation device, improve the cooling efficiency, and ensure the stable operation of the power device.

[0044] In addition, when the temperature difference between the central area and the peripheral area of the heat dissipation device is large, long-term operation may also cause thermal deformation of the outer casing 1, and then cause changes in the contact thermal resistance of each part of the outer casing 1, affecting the cooling performance of the heat dissipation device. And through the above settings in the present application, the consistency of the temperatures of each part of the outer casing 1 is improved, which can effectively solve this problem, reduce the deformation amount during the long-term use of the outer casing, and ensure the cooling performance of the heat dissipation device.

[0045] Refer to Figure 4 , as an implementation manner of the present application, a first groove 131 is opened on the first side wall 13, and a second groove 141 is opened on the second side wall 14. The two ends of the heat pipe 21 are respectively located in the first groove 131 and the second groove 141. Of course, in some other implementation manners, according to actual application requirements, only the first groove 131 may be opened on the first side wall 13, or only the second groove 141 may be opened on the second side wall 14, so that one end of the heat pipe 21 is located in the first groove 131 or the second groove 141.

[0046] Since both the first side wall 13 and the second side wall 14 have a certain thickness, on the premise of ensuring the structural strength of the outer housing 1, a first groove 131 is formed on the first side wall 13, and a second groove 141 is formed on the second side wall 14, which can increase the contact area between both ends of the heat pipe 21 and the first side wall 13 and the second side wall 14, thereby improving the heat exchange efficiency between the end with a larger heat generation amount and the end with a smaller heat generation amount.

[0047] As described above, the present application has taken the heat pipe 21 as an example for exemplary illustration, but in practical applications, the form of the heat conduction structure 2 is not limited thereto.

[0048] For example, in one implementation, the heat conduction structure 2 may be a heat conduction rod connected between the first side wall 13 and the second side wall 14. The heat conduction rod may be a metal material with high heat conduction performance, such as aluminum alloy, etc., so that it can not only meet the support requirements, but also enable heat to be directly transferred along the heat conduction rod.

[0049] It should be noted that considering that in practical applications, the heat conduction rod itself will also occupy a certain space, therefore, the cross-sectional size of the heat conduction rod itself should not be too large, so as to reserve most of the space in the cavity 100 for the cooling working medium to ensure the cooling effect.

[0050] In another implementation, the heat conduction structure 2 may further include a second tube body and a phase change material disposed in the second tube body, and both ends of the second tube body are respectively connected to the first side wall 13 and the second side wall 14.

[0051] In an embodiment of the present application, the phase change material may adopt a solid-liquid phase change material. The solid-liquid phase change material changes its physical phase from solid to liquid when the temperature is higher than the phase change point, absorbing heat, and when the temperature drops, the physical phase changes from liquid to solid again, releasing heat. The solid-liquid phase change material has good formability in the solid state, no precipitation phenomenon, stable performance, and no corrosion. In the present application, the solid-liquid phase change material may adopt organic phase change materials, such as paraffin, alcohols, esters, aromatic hydrocarbons, aromatic ketones, and amides, etc., or may also adopt inorganic phase change materials such as crystalline hydrated salts and molten salts. The present application does not limit this.

[0052] It should be noted that in some implementations, the phase change material may also adopt a solid-gas phase change material. Although the phase change latent heat of the solid-gas state is very high, due to the large volume change, the space requirement for the system will also increase. Therefore, in practical applications, the specific form of the phase change material should be selected according to various requirements.

[0053] In addition, according to actual requirements, both ends of the tube body may be closed or open. When both ends of the tube body are open, the solid-liquid phase change material is in direct contact with the first side wall 13 and the second side wall 14 to enhance the heat exchange effect.

[0054] It should be noted that although in the above embodiments of the present application, the example is described with power devices provided on both side surfaces of the heat dissipation device, in actual applications, it is not limited to this. It is also possible to attach the device to be cooled only on the first side wall 13 or the second side wall 14 of the heat dissipation device. At this time, the side surface of the heat dissipation device that is not attached to the device to be cooled is the cooler side. The heat conduction structure 2 also transfers the heat on the side where the device to be cooled is attached to the above-mentioned cooler side to achieve heat transfer and improve the uniformity of the temperature distribution on both sides of the heat dissipation device, thereby improving the cooling efficiency.

[0055] It should also be noted that the heat dissipation device is not limited to being applied to the above-mentioned power devices. The heat dissipation device is also applicable to other application scenarios that require heat dissipation to improve the cooling efficiency. The heat dissipation device is not limited to the uneven heat generation between the emitter and the collector of the power device. In some other application scenarios with uneven heat generation, as long as there is a temperature difference between the two side surfaces of the heat dissipation device, the heat dissipation device of the present application can be used for improvement.

[0056] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principle of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. A heat dissipation device, characterized in that: include: An outer shell, wherein a cavity for accommodating a cooling medium is formed inside the outer shell, an inlet and an outlet communicating with the cavity are respectively arranged on the outer shell, and the outer shell has a first side wall and a second side wall opposite to each other; as well as A heat-conducting structure is disposed in the cavity, and two ends of the heat-conducting structure are respectively connected to the first side wall and the second side wall.

2. The heat dissipation device according to claim 1, characterized in that: The heat conducting structure is a heat pipe.

3. The heat dissipation device according to claim 2, characterized in that: A plurality of heat pipes are arranged in the cavity.

4. The heat dissipation device according to claim 3, characterized in that: The plurality of heat pipes are arranged in a linear array or a circular array.

5. The heat dissipation device according to claim 3, characterized in that: The arrangement density of the heat pipes gradually decreases from the center of the cavity to the periphery.

6. The heat dissipation device according to claim 3, characterized in that: An axis of the heat pipe is perpendicular to the first side wall and the second side wall.

7. The heat dissipation device according to claim 2, characterized in that: A first groove is formed on the first side wall, and one end of the heat pipe is located in the first groove; and / or A second groove is formed on the second side wall, and the other end of the heat pipe is located in the second groove.

8. The heat dissipation device according to any one of claims 2 to 7, characterized in that: The heat-conducting structure further includes a first tube body connected between the first side wall and the second side wall, and the heat pipe is located in the first tube body.

9. The heat dissipation device according to claim 1, characterized in that: The heat-conducting structure includes a second tube body and a phase-change material filled in the second tube body, and two ends of the second tube body are respectively connected to the first side wall and the second side wall.

10. The heat dissipation device according to claim 1, characterized in that: The heat-conducting structure is a heat-conducting rod connected between the first side wall and the second side wall.

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