A heat dissipation device with a working medium guide structure

Abstract

The present invention relates to a heat dissipation device with a working medium flow guide structure. In the device, a working medium circulation structure is arranged inside a heat transfer cavity of a heat dissipation body and is filled with working medium. The working medium circulation structure is a single-layer or multi-layer cylindrical structure with an open bottom. The evaporation surface in the heat transfer cavity and the outer surfaces of the side walls of the working medium circulation structure have a capillary structure. The distance between the inner wall of the heat transfer cavity and the outer surfaces of the side walls of the working medium circulation structure, as well as between the side walls, is greater than or equal to 0.05d. g Less than or equal to 0.8d g ;d g This is the ideal droplet diameter of the working fluid at normal temperature and pressure. The present invention utilizes the dual forces of capillary suction and working fluid tension to act on the working fluid, causing it to flow back onto the surface of the evaporation layer. This eliminates any gravitational direction requirements for the heat dissipation device, achieving non-directional restrictions and enhancing the working fluid return effect, thereby improving the heat dissipation effect.

Description

Technical Field

[0001] The invention belongs to the technical field of heat dissipation devices and relates to a heat dissipation device with a working medium flow guiding circulation structure. Background Art

[0002] Current conductive heat dissipation technologies include heat pipes, thermal columns, and microgrooved phase change technologies. All of these conductive heat dissipation technologies utilize capillary action. Heat pipes and thermal columns have greater fluid conductivity and are therefore more expensive to manufacture. Microgrooved phase change technology has weaker fluid conductivity, a less pronounced capillary effect, and requires clear directional control. However, it also simplifies manufacturing and reduces costs.

[0003] The Chinese Patent Gazette published a "heat column manufacturing method" (Patent No.: CN 101846472 B), which resulted in two products: a "high-bay lamp heat sink" (Patent No.: CN 203857440 U), and an "assembled high-power LED lamp heat sink" (Patent No.: CN 211011275 U). These patents describe the use of heat columns to manufacture two heat sinks and LED lamps that meet heat dissipation requirements. The disadvantages of this method are: 1. Although the copper tube heat column is an innovative development of traditional thin heat pipes, its maximum diameter is still relatively small. In the case of the "high-bay lamp heat sink," the relatively small copper tube heat column requires the use of larger heat sinks to increase the heat dissipation area. 2. Using heat columns to manufacture the heat sink creates thermal resistance. The sleeve and heat column are formed by interference fit. Due to the insufficient heat dissipation area, additional heat sinks are required, which further increases the interference fit and creates thermal resistance. 3. Regarding the "Assembled High-Power LED Lamp Heat Sink," because the diameter of the copper tube heat column cannot be increased significantly, multiple heat columns must be used, which is very limited. 4. Adding multiple heat columns increases manufacturing costs. 5. The heat column itself relies on condensation to form droplets, which then reflow. If the heat column is not arranged vertically, the heat dissipation effect will be relatively poor.

[0004] A Chinese patent publication discloses a "heat pipe heat dissipation device" (patent number: CN 214960711 U). The disadvantages of this method are: 1. The manufacturing process is complex and the cost is high. 2. The heat sink takes up product space and requires additional exterior accessories, which does not save materials and form an integrated product.

[0005] A Chinese patent publication discloses a "fin-type heat sink" (patent number: CN 216357981 U), which uses a traditional heat pipe radiator. Disadvantages include: 1. The manufacturing process is complex and the cost is high. 2. The radiator takes up product space and requires additional exterior accessories, preventing the integration of materials into a single product. 3. It has high constraints and limited product scalability. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a heat dissipation device with a working medium guide structure, which has no requirements on the direction of gravity and can achieve good heat dissipation effect in any direction.

[0007] In order to solve the above technical problems, the heat dissipation device with a working medium guide structure of the present invention can adopt the following two technical solutions.

[0008] Technical Solution 1

[0009] The heat dissipation device with a working medium flow guide structure of the present invention is characterized in that a working medium circulation structure is provided inside the heat transfer cavity of the heat dissipation body and is filled with working medium; the working medium circulation structure is a single-layer cylindrical structure with an open bottom; the evaporation surface in the heat transfer cavity and the outer surface of the side wall of the working medium circulation structure both have a capillary structure; the distance between the inner wall of the heat transfer cavity and the outer surface of the side wall of the working medium circulation structure is La, 0.05d g ≤La≤0.8d g ;d g It is the ideal droplet diameter of the working fluid at normal temperature and pressure.

[0010] The inner surface of the side wall of the working medium circulation structure has a capillary structure.

[0011] Technical Solution 2

[0012] The heat dissipation device with a working medium flow guide structure of the present invention is characterized in that a working medium circulation structure is arranged inside the heat transfer cavity of the heat dissipation body and is filled with working medium; the working medium circulation structure is a 2-3 layer cylindrical structure with an open bottom, the evaporation surface in the heat transfer cavity and the outer surface of each layer of side wall have a capillary structure; the distance between the inner wall of the heat transfer cavity and the outer surface of the first layer of side wall, and the air gap between two adjacent layers of side walls are both greater than or equal to 0.05d g and less than or equal to 0.8d g ;d g It is the ideal droplet diameter of the working fluid at normal temperature and pressure.

[0013] The inner surface of each layer of the side wall has a capillary structure.

[0014] The working medium circulation structure has a top reflux layer, the upper surface of which has a capillary structure; the distance between the upper surface of the top reflux layer and the top surface of the heat transfer cavity is Lb, 0.05d g ≤Lb≤d g .

[0015] The lower surface of the top reflux layer has a capillary structure.

[0016] The working medium circulation structure has 2-3 layers of top return layers, and the upper surface of each layer of top return layer has a capillary structure; the distance between the upper surface of the first layer of top return layer and the top surface of the heat transfer cavity, and the air gap between two adjacent layers of top return layers are greater than or equal to 0.05d g and less than or equal to d g .

[0017] The lower surface of each top reflux layer has a capillary structure.

[0018] The top reflux layer is a full reflux layer or a half reflux layer.

[0019] Side vias are distributed on each side wall of the working medium circulation structure, and top vias are distributed on each top return layer.

[0020] The working fluid is water, lipids, alcohol liquid, or solid working fluid.

[0021] The upper surface of the lower cover of the heat transfer chamber serves as the evaporation surface, while the lower surface serves as the heat source. A heat source is placed at the heat source end. After the heat source heats the working fluid, the fluid undergoes a phase change, transforming into gas. The gas reaches the cold end and condenses into liquid. The working fluid circulation structure utilizes liquid tension and capillary action to cause the liquid to flow back to the hot end. This process is repeated to achieve heat transfer. Heat passes through the heat transfer chamber, and then, through changes in the heat sink fins, most of the heat from the heat source end is transferred to the atmosphere through convection. By varying the internal pressure or vacuum level of the heat transfer chamber, the boiling point of the working fluid can be altered, thereby adapting to the requirements of heat sinks in different temperature ranges.

[0022] The present invention has the following advantages:

[0023] 1. The dual forces of capillary suction and working fluid tension are used to act on the working fluid, so that the working fluid flows back to the surface of the evaporation layer. There is no requirement for the direction of gravity for the heat dissipation device, which realizes non-directional restriction and improves the working fluid reflux effect, thereby improving the heat dissipation effect.

[0024] 2. The outer shell can be omitted to realize the integrated design of the product, making the product more compact and saving the design space of the product.

[0025] 3. It can be made by die-casting, profile and other processes, with simple structure and lower manufacturing cost.

[0026] 4. Because the heat transfer structure is inside, the heat transfer of the product can be integrated, saving product usage space.

[0027] The present invention can ensure the stability and reliability of thermal components that require heat dissipation during long-term use, and is suitable for thermal management of high-performance computers, high-power lasers, and high-power power electronic equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Figure 1 It is a stereogram of embodiment 1 of the present invention.

[0030] Figure 2 This is a cross-sectional view of Example 1.

[0031] Figure 3 It is a three-dimensional diagram of the working medium diversion circulation structure of Example 1.

[0032] Figure 4 It is a cross-sectional view of the working medium diversion circulation structure of Example 1.

[0033] Figure 5 It is a three-dimensional diagram of the working medium diversion circulation structure of Example 2.

[0034] Figure 6 It is a top view of the working medium diversion circulation structure of Example 3.

[0035] Figure 7 、 Figure 8 This is a perspective view of Example 4.

[0036] Figure 9 This is a bottom view of Example 4.

[0037] Figure 10 This is a cross-sectional view of Example 4.

[0038] Figure 10a yes Figure 10 A partial enlarged view of .

[0039] Figure 10b yes Figure 10 B is a partial enlarged view of .

[0040] Figure 11 It is a three-dimensional diagram of the working medium diversion circulation structure of Example 4.

[0041] Figure 12 It is a three-dimensional diagram of the working medium diversion circulation structure of Example 5.

[0042] Figure 13 It is a schematic diagram of the present invention when tilted.

[0043] In the figure: 1. Heat dissipation substrate, 11. Flow hole, 2. Heat dissipation body, 21. Fins, 22. Heat transfer cavity, 221. Lower cover, 222. Upper cover, 223. Sealing screws, 3. Working medium circulation structure, 31. Side wall, 32. Top return layer, 33. Side via, 34. Top via, 321. Opening, 311. First layer side wall, 312. Second layer side wall, 313. Third layer side wall, 321. First layer top return layer, 322. Second layer top return layer. DETAILED DESCRIPTION

[0044] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, rather than all structures.

[0045] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0046] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," or "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," or "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0047] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are used to refer to positions or locations based on those shown in the accompanying drawings. These terms are intended solely to facilitate description and simplify operation, and are not intended to indicate or imply that the devices or components referred to must be oriented, constructed, or operated in a specific manner. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0048] Example 1: Full reflux form

[0049] like Figure 1-4 As shown, the heat dissipation device with a working medium flow guiding structure of the present invention includes a heat dissipation body 2 and a working medium circulation structure 3.

[0050] The heat dissipation body 2 is formed by a profile, with fins 21 distributed around it and a heat transfer cavity 22 in the middle part; the lower cover 221 and the upper cover 222 are respectively fixed to the bottom and top of the heat transfer cavity 22 by double-end interference fit; the upper surface of the lower cover 221 is the evaporation surface, which has a capillary structure; the central threaded hole of the upper cover 222 is connected to the sealing screw 223, and the heat transfer cavity is filled with a working medium.

[0051] The working medium circulation structure 3 is located within the heat transfer chamber and is a single-layer cylindrical structure with an open bottom. The outer surface of the sidewall 31 and the upper surface of the top return layer 32 both have capillary structures. The inner surface of the sidewall 31 and the lower surface of the top return layer 32 may also have capillary structures. Side vias 33 are distributed on the sidewall, and top vias 34 are distributed on the top return layer to increase the flow of the vaporous working medium. When both the inner and outer surfaces of the sidewall 31 and the upper and lower surfaces of the top return layer 32 have capillary structures, the heat dissipation effect is better than when only the outer surface of the sidewall 31 and the upper surface of the top return layer 32 have capillary structures.

[0052] The top reflux layer 32 is a full reflux layer.

[0053] Assume that the ideal droplet diameter of the working fluid at normal temperature and pressure is d g The distance between the inner wall of the heat transfer cavity and the outer surface of the side wall 31 of the working medium circulation structure is La, and the distance between the top surface of the heat transfer cavity and the upper surface of the recirculation layer 32 at the top of the working medium circulation structure is Lb, then 0.05d g ≤La≤0.8d g , 0.05d g ≤Lb≤d g ; σ is the working fluid tension, ρ is the working fluid density, and g is the acceleration due to gravity.

[0054] Example 2: Semi-recirculation layer form

[0055] like Figure 5 As shown, the only difference between this embodiment and embodiment 1 is that the top recirculation layer 32 of the working medium circulation structure 3 is a semi-recirculation layer, and the semi-recirculation layer is a plurality of inner edges distributed circumferentially at the top.

[0056] Example 3: Semi-recirculation layer form

[0057] like Figure 6 As shown, the only difference between this embodiment and embodiment 1 is that the top recirculation layer 32 of the working medium circulation structure is a semi-recirculation layer, and the semi-recirculation layer is formed by processing an opening 321 in the middle part of the full recirculation layer.

[0058] The heat dissipation effect test data of Examples 1-3 under the conditions of a heat transfer cavity inner diameter of 97 mm, a heat transfer cavity height of 68 mm, water (dg≈9.44 mm), a vacuum degree of -0.095 MPa, and capillary structures on the inner and outer surfaces of the side wall 31 and the upper and lower surfaces of the top reflow layer 32 are shown in Table 1.

[0059] The full reflux form is better than the semi-reflux or no reflux form.

[0060] Example 1: La = 0.05 dg Lb = 0.05 dg

[0061] Example 2: La = 0.8 dg Lb = dg

[0062] Example 3: La = 0.4 dg Lb = 0.5 dg

[0063] The full reflux form is better than the semi-reflux or no reflux form.

[0064] Table 1

[0065]

[0066] Example 4: Full reflux layer form

[0067] like Figure 7-12 As shown, the heat dissipation device with a working medium flow guiding structure of the present invention includes a die-cast heat dissipation substrate 1, a heat dissipation body 2, and a working medium circulation structure 3.

[0068] The heat dissipation substrate 1 is provided with a plurality of rectangular, waist-shaped or other shaped flow holes 11 for increasing the fluidity of the air.

[0069] The heat dissipation body 2 is located on the heat dissipation substrate 1, and the two can be die-cast; fins 21 are distributed around the heat dissipation body 2, and a heat transfer cavity 22 is provided in the middle portion; the heat transfer cavity lower cover 221 and the heat transfer cavity upper cover 222 are respectively fixed to the bottom and top of the heat transfer cavity 22 by double-end interference fit; the upper surface of the heat transfer cavity lower cover 221 is the evaporation surface, which has a capillary structure; the central threaded hole of the heat transfer cavity upper cover 222 is connected to a sealing screw 223, and the heat transfer cavity is filled with a working medium.

[0070] The working medium circulation structure 3 is arranged inside the heat transfer cavity and is a multi-layer cylindrical structure with an opening at the bottom. The structure has three side walls and two top return layers. When the inner and outer surfaces of the three side walls and the upper and lower surfaces of the two top return layers have capillary structures, the heat dissipation effect is better than when only the outer surfaces of the side walls and the upper surfaces of the top return layers have capillary structures; side through holes 33 are distributed on the three side walls, and top through holes 34 are distributed on the two top return layers to increase the flow of vaporous working medium.

[0071] like Figure 10a 、 Figure 10b As shown, the ideal droplet diameter of the working fluid at normal temperature and pressure is d g The distance between the inner wall of the heat transfer cavity and the outer surface of the first side wall 311 of the working medium circulation structure is La1, the distance between the inner surface of the first side wall 311 of the working medium circulation structure and the outer surface of the second side wall 312 is La2, and the distance between the inner surface of the second side wall 312 of the working medium circulation structure and the outer surface of the third side wall 313 is La3; the distance between the top surface of the heat transfer cavity and the upper surface of the first top return layer 321 of the working medium circulation structure is Lb1, and the distance between the lower surface of the first top return layer 321 of the working medium circulation structure and the upper surface of the second top return layer 322 is Lb2; then 0.05d g ≤La1≤0.8d g , 0.05d g ≤La2≤0.8d g , 0.05d g ≤La3≤0.8d g , 0.05d g ≤Lb1<d g , 0.05d g ≤Lb2<d g ; σ is the working fluid tension, ρ is the working fluid density, and g is the acceleration due to gravity.

[0072] Example 5: No reflux layer

[0073] like Figure 13 As shown, the difference between this embodiment and embodiment 1 is that the top of the working medium circulation structure is open and there is no recirculation layer.

[0074] Table 2 shows the test data of the heat dissipation effect of Examples 4 and 5 under the conditions that the inner diameter of the heat transfer cavity is 97 mm, the height of the heat transfer cavity is 68 mm, the working fluid is water (dg≈9.44 mm), the vacuum degree is -0.095 MPa, and the inner and outer surfaces of the side wall 31 and the upper and lower surfaces of the top reflow layer 32 all have capillary structures.

[0075] Example 4: La1 = 0.05dg, La2 = 0.05dg, La3 = 0.05dg, Lb1 = 0.05dg, Lb2 = 0.05d.

[0076] Example 5: La1=0.8dg, La2=0.8dg, La3=0.8dg, Lb1=dg, Lb2=dg.

[0077] Table 2

[0078]

[0079] The material of the working medium flow guiding circulation structure in each embodiment can be copper, and the capillary structure is made of copper powder sintering structure, channel structure, and wire mesh structure.

[0080] The heat dissipation body, the sealing cover and the sealing screws in each embodiment can be made of aluminum, and the sealing rubber ring can be made of silicone.

[0081] After the working medium is injected into the heat transfer cavity, vacuum equipment is used to evacuate the cavity according to the required vacuum degree, and finally the heat transfer cavity is sealed using the breakable sealing screw 223 .

[0082] The heat dissipation body and the working medium flow guiding circulation structure can be fixed by interference pressing or welding.

[0083] The present invention is not limited to the above embodiments. Figure 1 、 Figure 8 In both structural forms, the working fluid circulation structure can be single-layer or multi-layer, with full recirculation, semi-recirculation, or no recirculation. Distributing multiple vias on the sidewalls and top recirculation layer of the working fluid circulation structure achieves better heat dissipation than without vias. When both the sidewalls and top recirculation layer of the working fluid circulation structure are multi-layered, capillary structures can be incorporated into portions of their outer and inner surfaces.

[0084] The working fluid can be liquid or solid working fluid such as water, lipids, alcohols, etc. at room temperature.

[0085] When the heat sink tilt angle α is less than 90°, La has the greatest impact on the heat dissipation effect, while Lb has a relatively small improvement on performance. When the heat sink tilt angle α is greater than 90°, both La and Lb have a significant impact on the heat dissipation effect.

[0086] Comparative Examples 1 to 3 are heat dissipation devices in which no working medium flow circulation structure is provided inside the heat transfer cavity. The test results are shown in Table 3 (ambient temperature: 25° C.).

[0087] Table 3

[0088] Comparative Example 1 Comparative Example 2 Comparative Example 3 1 hour 74.3℃ 75.1℃ 75.0℃ 24 hours 73.9℃ 74.9℃ 75.5℃ 72 hours 74.5℃ 74.3℃ 74.9℃ 144 hours 74.6℃ 74.9℃ 75.2℃ .

Claims

1. A heat dissipation device with a working medium guide structure, characterized in that A working medium circulation structure (3) is provided inside the heat transfer cavity of the heat dissipation body (2) and is filled with working medium; the working medium circulation structure (3) is a single-layer cylindrical structure with an open bottom; the evaporation surface in the heat transfer cavity and the outer surface of the side wall (31) of the working medium circulation structure (3) both have a capillary structure; the distance between the inner wall of the heat transfer cavity and the outer surface of the side wall (31) of the working medium circulation structure is La, 0.05d g ≤La≤0.8d g ;d g is the ideal droplet diameter of the working medium under normal temperature and pressure conditions; the working medium circulation structure (3) has a top reflux layer (32), the upper surface of which has a capillary structure; the distance between the upper surface of the top reflux layer (32) and the top surface of the heat transfer cavity is Lb, 0.05d g ≤Lb≤d g .

2. The heat dissipation device with a working medium guide structure according to claim 1, characterized in that The inner surface of the side wall (31) of the working medium circulation structure (3) has a capillary structure.

3. A heat dissipation device with a working medium guide structure, characterized in that A working medium circulation structure (3) is provided inside the heat transfer cavity of the heat dissipation body (2) and is filled with working medium; the working medium circulation structure (3) is a 2-3 layer cylindrical structure with an open bottom, and the evaporation surface in the heat transfer cavity and the outer surface of each layer of side wall have a capillary structure; the distance between the inner wall of the heat transfer cavity and the outer surface of the first layer of side wall (31) and the air gap between two adjacent layers of side walls are both greater than or equal to 0.05d g and less than or equal to 0.8d g ;d g is the ideal droplet diameter of the working medium under normal temperature and pressure conditions; the working medium circulation structure (3) has a top reflux layer (32), the upper surface of which has a capillary structure; the distance between the upper surface of the top reflux layer (32) and the top surface of the heat transfer cavity is Lb, 0.05d g ≤Lb≤d g .

4. The heat dissipation device with a working medium guide structure according to claim 3, characterized in that The inner surface of each layer of the side wall has a capillary structure.

5. The heat dissipation device with a working medium guide structure according to claim 1, characterized in that The lower surface of the top return layer (32) has a capillary structure.

6. The heat dissipation device with a working medium guide structure according to claim 1 or 2, characterized in that The working medium circulation structure (3) has 2-3 layers of top return layers (32), and the upper surface of each layer of the top return layer (32) has a capillary structure; the distance between the upper surface of the first layer of the top return layer (32) and the top surface of the heat transfer cavity, and the air gap between two adjacent layers of the top return layer (32) are both greater than or equal to 0.05d g and less than or equal to d g .

7. The heat dissipation device with a working medium guide structure according to claim 6, characterized in that The lower surface of each top reflow layer (32) has a capillary structure.

8. The heat dissipation device with a working medium guide structure according to claim 6, characterized in that The top reflux layer (32) is a full reflux layer or a half reflux layer.

9. The heat dissipation device with a working medium guide structure according to claim 6, characterized in that Side vias (33) are distributed on each side wall of the working medium circulation structure (3), and top vias (34) are distributed on each top reflow layer (32).

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