Bending type vapor chamber condensation end lifting structure and gravity backflow enhancing method

Abstract

The invention relates to a bent vapor chamber condensation end lifting structure and a gravity backflow enhancing method, and belongs to the technical field of vapor chambers. A condensation section of a vapor chamber is bent upwards relative to an evaporation section to form a height difference, and condensate backflow is enhanced through gravitational potential energy; the structure of the vapor chamber unit is divided into functional zones of an evaporation section and a condensation section, the condensation section is bent upwards to form spatial dislocation, so that the condensation section is higher than the evaporation section in the gravity direction, a natural gravity backflow path is created in working medium circulation, and an inclined surface generated by a bent structure provides a directional flow guide effect for condensate. The liquid working medium can automatically flow to the evaporation section along the surface by virtue of gravity, so that single dependence on capillary force is reduced, the problem of working medium supply interruption caused by insufficient capillary force is effectively avoided, and the problems of insufficient reflux driving force and low working efficiency caused by insufficient reflux driving force due to lack of gravitational potential energy when the vapor chamber is in an approximately horizontal mounting state are solved. The liquid supply of the evaporation section is insufficient; and the heat dissipation efficiency is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of uniform temperature plates, and particularly relates to a bent uniform temperature plate condensing end lifting structure and a gravity backflow enhancement method. BACKGROUND

[0002] As a kind of high-efficiency heat dissipation element, the uniform temperature plate is mainly applied to the heat management of power devices and electronic equipment, and its basic working principle is that the evaporating end vaporizes the working medium after absorbing heat, the steam diffuses to the condensing end to release latent heat and condenses into liquid, and the condensed liquid backflows to the evaporating end to realize a continuous cycle. In the traditional uniform temperature plate, the working medium backflow mainly depends on the capillary force of the capillary structure and the partial gravity effect in the favorable installation posture, so as to maintain the stable liquid supply of the evaporating end and the heat dissipation efficiency.

[0003] However, when the uniform temperature plate is in a near-horizontal installation state, the height difference of the condensing section and the evaporating section in the gravity direction is close to zero, and the condensed liquid cannot obtain the gravity potential energy as the backflow driving force. In this case, the backflow mainly depends on the capillary force, and as the power density of the power device increases, the evaporating end needs a higher liquid supply amount, and the flow resistance in the backflow channel increases. When the pressure difference provided by the capillary force is insufficient to overcome the backflow resistance, the evaporating end will dry out due to insufficient liquid supply, resulting in a significant increase in thermal resistance and even causing the device to overheat and burn out. Especially in the application scenarios of multiple heat sources or high heat flux density, the condensed liquid needs to backflow through a longer path, and the resistance further accumulates, and the problem is more serious. This series of problems show that the existing uniform temperature plate is severely limited by the working medium backflow capacity in terms of heat dissipation efficiency and operation stability. To solve this problem, a bent uniform temperature plate condensing end lifting structure and a gravity backflow enhancement method are provided. SUMMARY

[0004] To solve the problem that the condensed liquid lacks gravity potential energy in the existing uniform temperature plate in a near-horizontal installation state, thereby causing insufficient backflow driving force and leading to insufficient liquid supply of the evaporating section and decreased heat dissipation efficiency, the present application provides a bent uniform temperature plate condensing end lifting structure and a gravity backflow enhancement method.

[0005] The purpose of the present application can be achieved by the following technical solutions: A bent uniform temperature plate condensing end lifting structure, comprising a uniform temperature plate unit, the uniform temperature plate unit comprising an evaporating section and a condensing section, the condensing section being bent upward relative to the evaporating section to form a bent structure, so that the condensing section is higher than the evaporating section in the gravity direction, and the bent structure forms a height difference, so that the condensed liquid working medium backflows to the evaporating section along the inclined surface under the action of gravity.

[0006] As a further scheme of the present application, the uniform temperature plate unit is a U-shaped bending structure, which comprises two vertical segments and a horizontal segment, two ends of the horizontal segment are connected with the two vertical segments respectively, and the condensing segment is located above the horizontal segment.

[0007] As a further scheme of the present application, the outer surface of the condensing segment is provided with first heat dissipation fins.

[0008] As a further scheme of the present application, the bending angle of the condensing segment bending upward relative to the evaporating segment is between 8° and 20°.

[0009] As a further scheme of the present application, the horizontal segment of the U-shaped bending structure is provided with a bottom plate, a plurality of discrete heat sources are arranged on the bottom plate, and the evaporating segment corresponds to the positions of the plurality of heat sources and covers the heat sources.

[0010] As a further scheme of the present application, the uniform temperature plate unit is a plurality of units, and the vertical segments of adjacent uniform temperature plate units are attached, and second heat dissipation fins are arranged between the two vertical segments of each uniform temperature plate unit.

[0011] A bending type uniform temperature plate gravity backflow enhancement method, comprising the following steps: S1: dividing the internal working chamber of the uniform temperature plate into an evaporating area, a bending transition area and a condensing area according to functions and spatial positions, wherein the condensing area is arranged above the evaporating area in the gravity direction and is communicated with the evaporating area through the bending transition area to form a U-shaped structure circuit; S2: arranging a dense microchannel network on the upper wall surface and the adjacent side wall area of the inner wall of the evaporating area opposite to the heat source, and applying a first lyophilic surface treatment to all the inner wall surfaces of the area to form the maximum capillary driving force and the liquid absorption capacity for continuously supplying the required liquid phase working medium at the heat source, and arranging a weak lyophilic structure on the uncovered area of the remaining inner wall of the evaporating area to prevent liquid flow deviation; S3: arranging sparse microchannels on the top inner surface and the upper side inner wall surface of the condensing area and applying a third lyophilic surface treatment to promote the condensing liquid to quickly separate from the condensing surface under the action of gravity and flow into the area below, and the remaining inner wall surface in the area is treated with a smooth metal surface to reduce unnecessary liquid stagnation and capillary retention; S4: arranging a flow guide groove structure connected with S2 and S3 on the inner wall of the lower concave turning surface of the bending transition area, the flow guide groove is between the evaporating area and the condensing area in terms of channel width and spacing, and a second lyophilic surface treatment is applied to seamlessly receive the liquid from the condensing area and guide it to flow smoothly to the evaporating area.

[0012] As a further scheme of the present application, the wettability of the first, second and third wettability surface treatments decreases in turn.

[0013] As a further scheme of the present application, the channel width of the microchannel network arranged in the evaporation area is 0.2mm-0.5mm, the channel spacing is not greater than 0.5mm, and the wettability surface treatment has a contact angle of not greater than 20°; the channel width of the flow guide groove in the bending transition area is 0.5mm-1.0mm, the channel spacing is 0.8mm-1.5mm, and the contact angle of the surface after wettability treatment is between 20° and 40°; the channel width of the sparse guide channel arranged in the condensation area is 1.0mm-1.5mm, the spacing is greater than 2mm, and the surface contact angle is controlled to be between 40° and 60°.

[0014] As a further scheme of the present application, the flow guide groove is one of an axial groove, a spiral groove or a mesh groove.

[0015] The beneficial effects of the present application are: By bending the condensation section of the vapor chamber upward relative to the evaporation section to form a height difference, the gravitational potential is used to strengthen the return flow of the condensate, the structure of the vapor chamber unit is clear in function division of the evaporation section and the condensation section, the space formed by bending the condensation section upward is misaligned, the condensation section is higher than the evaporation section in the direction of gravity, thereby creating a natural gravity return path in the working fluid circulation, the inclined surface generated by the bending structure provides directional flow guiding for the condensate, and the liquid working fluid can flow to the evaporation section along the surface relying on gravity, reducing the single dependence on capillary force. This design directly improves the return flow driving force through physical structure change, is especially suitable for horizontal or near-horizontal installation scenarios, effectively avoids the problem of interruption of working fluid supply caused by insufficient capillary force, and solves the problem of insufficient evaporation section liquid supply and reduced heat dissipation efficiency caused by insufficient return flow driving force of the condensate due to lack of gravitational potential in the vapor chamber in the near-horizontal installation state. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to facilitate understanding of those skilled in the art, the present application will be further described below with reference to the accompanying drawings.

[0017] Figure 1 is a schematic diagram of the overall structure of the present application; Figure 2 is a schematic diagram of the installation position of the vapor chamber unit of the present application; Figure 3 is a schematic diagram of the structure of the vapor chamber unit of the present application; Figure 4 is a schematic diagram of the U-shaped bending structure of the vapor chamber unit of the present application; Figure 5 is a schematic diagram of the installation of multiple vapor chamber units of the present application; Figure 6 Flow chart of the gravity backflow enhancement method for the bent vapor chamber of the present application.

[0018] Legend: 1, vapor chamber unit; 2, evaporation section; 3, condensation section; 4, first heat dissipation fin; 5, bottom plate; 6, second heat dissipation fin; 7, heat source. DETAILED DESCRIPTION

[0019] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined inventive purpose, the specific embodiments, structures, features and effects according to the present application are described in detail below in combination with the drawings and preferred embodiments.

[0020] REFERENCE Figure 1 - Figure 6 The present embodiment provides a bent vapor chamber condensation end lifting structure, which comprises a vapor chamber unit 1, the vapor chamber unit 1 comprises an evaporation section 2 and a condensation section 3, the condensation section 3 is bent upwards relative to the evaporation section 2 to form a bent structure, so that the condensation section 3 is higher than the evaporation section 2 in the direction of gravity, the bent structure forms a height difference, so that the condensed liquid working medium flows back to the evaporation section 2 along the inclined surface under the action of gravity.

[0021] At present, as a kind of high-efficiency heat dissipation element, the vapor chamber is mainly applied in the thermal management of power devices and electronic equipment, and its basic working principle is: the evaporation end vaporizes the working medium after absorbing heat, the vapor diffuses to the condensation end to release latent heat and condenses into liquid, and the condensed liquid flows back to the evaporation end to realize a continuous cycle. In the traditional vapor chamber, the working medium backflow mainly depends on the capillary force of the capillary structure and the partial gravity effect under the favorable installation posture, so as to maintain the stable liquid supply of the evaporation end and the heat dissipation efficiency, however, when the vapor chamber is in a nearly horizontal installation state, the height difference between the condensation section 3 and the evaporation section 2 in the direction of gravity is close to zero, and the condensed liquid almost cannot obtain the gravitational potential energy as the backflow driving force, in this case, the backflow mainly depends on the capillary force, with the increase of the power density of the power device, the evaporation end needs a higher liquid supply amount, and the flow resistance in the backflow channel increases accordingly, when the pressure difference provided by the capillary force is insufficient to overcome the backflow resistance, the evaporation end will dry out due to insufficient liquid supply, resulting in a significant increase in thermal resistance and even causing the device to overheat and burn out, especially in the application scenarios of multiple heat sources 7 or high heat flux density, the condensed liquid needs to flow back through a longer path, and the resistance is further accumulated, and the problem is more prominent.

[0022] To solve the problem that the condensate lacks gravity potential in the near-horizontal installation state of the uniform temperature plate, causing insufficient return flow driving force, and further causing insufficient supply of liquid to the evaporation section 2 and reduced heat dissipation efficiency, in the present embodiment, the condensation section 3 of the uniform temperature plate is bent upward relative to the evaporation section 2 to form a height difference, and the gravity potential is used to strengthen the return flow of the condensate. The structure of the uniform temperature plate unit 1 clearly divides the functional zones of the evaporation section 2 and the condensation section 3. The space formed by the upward bending of the condensation section 3 is misaligned, causing the condensation section 3 to be higher than the evaporation section 2 in the direction of gravity. Thus, a natural gravity return flow path is created in the working medium cycle. The inclined surface produced by the bending structure provides directional flow guidance for the condensate. The liquid working medium can flow along the surface and rely on gravity to flow to the evaporation section 2, reducing the dependence on capillary force. This design directly improves the return flow driving force through physical structure changes, and is particularly suitable for horizontal or near-horizontal installation scenarios. It effectively avoids the problem of interrupted working medium supply caused by insufficient capillary force, and solves the problem of insufficient return flow driving force of the condensate due to the lack of gravity potential in the near-horizontal installation state of the uniform temperature plate, which further causes insufficient supply of liquid to the evaporation section 2 and reduced heat dissipation efficiency.

[0023] To avoid the working medium stagnation phenomenon caused by insufficient height difference in the traditional horizontal structure and further strengthen the return flow ability of the liquid working medium under gravity, in an embodiment, the uniform temperature plate unit 1 is a U-shaped bending structure. The U-shaped bending structure includes two vertical sections and a horizontal section. The two ends of the horizontal section are connected to the two vertical sections, respectively. The condensation section 3 is located above the horizontal section. By adopting the U-shaped bending structure, a stable spatial lifting architecture is formed by the geometric combination of the two vertical sections and the horizontal section. The two vertical sections serve as the support carriers for the evaporation section 2 and the condensation section 3, respectively. The horizontal section serves as the transition section connecting the two. The overall lifting of the condensation section 3 relative to the evaporation section 2 is achieved through a mechanical bending process. This structure fixes the condensation section 3 in the space above the horizontal section through the height extension of the vertical sections, thereby forming a clear height gradient in the direction of gravity. The horizontal section is the only passage for the return flow of the liquid working medium. The rigid connection of its two ends to the vertical sections ensures the continuity of the working medium flow path. The layout design of the condensation section 3 above the horizontal section allows the condensate to naturally drain along the inclined surface of the horizontal section or the inner wall of the vertical section after leaving the condensation surface, avoiding the working medium stagnation phenomenon caused by insufficient height difference in the traditional horizontal structure.

[0024] To avoid the problem of limited condensation speed of the working medium caused by insufficient heat dissipation efficiency of the condensation section 3 and improve the heat dissipation efficiency, in an embodiment, the outer surface of the condensation section 3 is provided with first heat dissipation fins 4. By providing the first heat dissipation fins 4 on the outer surface of the condensation section 3, the heat dissipation surface area of this region is significantly increased. The structural design of the heat dissipation fins can effectively improve the heat exchange efficiency between the condensation section 3 and the environment, accelerating the condensation phase change process of the vapor working medium and creating favorable conditions for the smooth return flow of the liquid working medium under the action of gravity.

[0025] To better solve the problem of insufficient gravity backflow driving force or excessive structural space occupation caused by unreasonable bending angle of the condensing section 3, in an embodiment, the bending angle of the condensing section 3 bent upward relative to the evaporating section 2 is between 8° and 20°. First, the angle is not the larger the better, but just enough to overcome the backflow resistance, while considering the whole machine posture change and stacking space. When there is a capillary core / micro-channel assistance, the device posture changes little, such as a desktop / fixed cabinet, the channel is wide, and the liquid path resistance is low. At this time, a small angle of 8°-12° is taken. When there is no capillary or the loop is long, the liquid channel is narrow, the heat flux is high, and the device often has a significant pitch, such as vehicle-mounted, airborne, and industrial mobile equipment. At this time, a large angle of 12°-20° is taken. By controlling the upward bending angle of the condensing section 3 relative to the evaporating section 2 within the range of 8° to 20°, the effective lifting height of the condensing section 3 in the gravity direction is ensured, and the problems of structural space waste caused by excessive bending angle or insufficient gravity potential caused by small angle are avoided. This angle range can form sufficient backflow driving force for the condensate under the action of gravity, while maintaining the compactness of the overall structure of the vapor chamber, ensuring that the liquid working medium forms a continuous and stable backflow path on the inclined surface. The lower limit of the bending angle of 8° ensures the minimum gravity potential threshold, and the upper limit of 20° prevents the increase of vapor flow resistance and the increase of processing difficulty caused by excessive bending. An optimal balance is achieved between heat dissipation efficiency and structural feasibility.

[0026] To better enable the evaporating section 2 of the vapor chamber to effectively cover more heat sources 7 without causing local dryout, in an embodiment, a bottom plate 5 is arranged on the horizontal section of the U-shaped bending structure, and a plurality of discrete heat sources 7 are arranged on the bottom plate 5. The evaporating section 2 corresponds to the positions of the plurality of heat sources 7 and covers the heat sources 7. By arranging a dedicated bottom plate 5 on the horizontal section of the U-shaped structure, a physical support platform is provided for the arrangement of multiple heat sources 7. The discrete heat sources 7 on the bottom plate 5 can be arranged in a manner suitable for the actual distribution of heat sources 7 in electronic equipment such as chipsets, and the positional correspondence between the evaporating section 2 and the heat sources 7 ensures that each independent heat source 7 can be directly covered by the evaporating area of the vapor chamber. This structure design solves the coverage blind area problem of traditional vapor chambers in the multi-heat source 7 scenario through spatial matching, enabling the evaporating section 2 to simultaneously absorb heat generated by multiple heat sources 7 and avoiding local dryout of the working medium caused by incomplete coverage of the heat sources 7. The precise correspondence of the coverage relationship also optimizes the heat conduction path and shortens the heat transfer distance from the heat sources 7 to the evaporating section 2.

[0027] To solve the problems of insufficient heat dissipation efficiency, loose structure layout and poor heat transfer between adjacent units when multiple uniform temperature plate units 1 are combined, in an embodiment, the uniform temperature plate unit 1 is several, and the vertical sections of adjacent uniform temperature plate units 1 are attached, and a second heat dissipation fin 6 is arranged between the two vertical sections of each uniform temperature plate unit 1. By arranging multiple uniform temperature plate units 1 in a way that the vertical sections are attached to each other, a compact integrated structure is formed, which effectively reduces the overall space occupied and enhances the heat conduction efficiency between units. On the basis of the attachment of adjacent vertical sections, a second heat dissipation fin 6 is additionally arranged between the two vertical sections of each uniform temperature plate unit 1. This fin not only expands the heat dissipation surface area to improve the heat dissipation capacity of a single unit, but also forms a heat bridge by physically connecting adjacent units to promote the lateral diffusion of heat between units and avoid local heat accumulation. The special arrangement position of the second heat dissipation fin 6 enables it to act on two adjacent vertical sections at the same time, optimizing the space utilization and achieving collaborative heat dissipation in the multiple heat source 7 scenario.

[0028] A bending type uniform temperature plate gravity backflow enhancement method, comprising the following steps: S1: The internal working chamber of the uniform temperature plate is divided into an evaporation region, a bending transition region and a condensation region according to function and spatial position, wherein the condensation region is arranged above the evaporation region in the gravity direction and is communicated with the evaporation region through the bending transition region to form a U-shaped structure circuit; S2: A dense microchannel network is arranged on the upper wall surface and the adjacent side wall region of the evaporation region opposite to the heat source 7, and a first lyophilic surface treatment is applied to all the inner wall surfaces of the region to form the maximum capillary driving force and liquid absorption capacity for continuously supplying the required liquid phase working medium at the heat source 7. Meanwhile, a weak lyophilic structure is arranged on the uncovered region of the remaining inner wall of the evaporation region to prevent liquid flow deviation; S3: Sparse microchannels are arranged on the top inner surface and the upper side inner wall surface of the condensation region, and a third lyophilic surface treatment is applied to promote the condensation liquid to quickly separate from the condensation surface under the action of gravity and flow into the lower region. The remaining inner wall surface in this region is treated with a smooth metal surface to reduce unnecessary liquid stagnation and capillary retention; S4: A flow guide groove structure is arranged on the inner wall of the lower concave turning surface of the bending transition region, which is communicated with S2 and S3. The flow guide groove is between the evaporation region and the condensation region in terms of channel width and spacing, and a second lyophilic surface treatment is applied to seamlessly receive the liquid from the condensation region and guide it to flow smoothly to the evaporation region.

[0029] It is worth mentioning that the bending type heat sink condensing end lifting structure solves the problem that the existing heat sink lacks gravity potential in the near horizontal installation state, which leads to insufficient backflow driving force, and further causes insufficient liquid supply in the evaporation section 2 and the problem of heat dissipation efficiency. On the basis of the bending type heat sink condensing end lifting structure, the gravity backflow is further enhanced. In this embodiment, the gravity and capillary force are realized by the cooperation of space structure division and surface characteristics. Step S1 constructs a U-shaped circuit to form a gravity potential difference, so that the condensate obtains a gravity backflow driving force; Step S2 sets a dense microchannel network at the position corresponding to the heat source 7 in the evaporation area, and strengthens the capillary suction force through the first lyophilicity treatment to ensure continuous supply of working medium under high heat flux, while the weak lyophilic structure avoids liquid retention in the non-heat source 7 area; Step S3 uses sparse microchannels and the third lyophilicity treatment at the top of the condensing area to reduce the capillary retention effect and promote the condensate to flow along the inclined surface under the action of gravity; Step S4 connects the evaporation and condensation areas through the flow guide groove in the bending transition area, and the second lyophilicity treatment balances the capillary force and gravity to realize seamless transition of the condensate from the high lyophilicity area to the low lyophilicity area. The design of the lyophilicity gradient decreasing in each area not only ensures the liquid supply strength of the evaporation end, but also avoids liquid retention in the condensing end, forming a gravity-dominated directional backflow path.

[0030] In order to better avoid the problem that the traditional heat sink lacks condensate backflow driving force in the horizontal installation state, and the capillary force cannot overcome the flow resistance, causing the evaporation end to dry up, the condensate backflow path is optimized through gradient lyophilicity surface treatment. In an embodiment, the lyophilicity of the first lyophilicity surface treatment, the second lyophilicity surface treatment and the third lyophilicity surface treatment decreases in turn. By establishing a gradient decreasing lyophilicity surface treatment system, directional flow control of the condensate from the evaporation end to the condensing end is realized. The strongest lyophilicity treatment is used in the evaporation area, and through the dense microchannel network and the maximum capillary driving force, the heat source 7 area is preferentially supplied with liquid working medium. The intermediate lyophilicity treatment is used in the transition area, which not only maintains the liquid conveying capacity of the flow guide groove, but also avoids excessive capillary force causing backflow resistance. The weakest lyophilicity treatment is used in the condensing area to reduce the surface retention effect, so that the condensate quickly separates under the action of gravity. Through the characteristics of strong suction in the evaporation end and weak retention in the condensing end, a capillary pressure difference is formed from the condensing end to the evaporation end, which cooperates with the gravity to enhance the backflow power. At the same time, the intermediate lyophilicity treatment in the transition area realizes the smooth connection of capillary driving force and gravity, preventing liquid accumulation or flow interruption at the interface of different areas.

[0031] Further, by optimizing the microchannel structure parameters and surface wettability treatment gradient of different regions inside the uniform temperature plate, and cooperating with gravity to realize efficient reflux of condensate, the problem of liquid supply dryout at the evaporation end of the traditional uniform temperature plate caused by insufficient capillary force is better solved. In an embodiment, the microchannel network arranged in the evaporation region has a channel width of 0.2 mm-0.5 mm, a channel spacing of not greater than 0.5 mm, and a wettability surface treatment with a contact angle of not greater than 20°. The flow guide groove channel width in the bending transition region is 0.5 mm-1.0 mm, the channel spacing is 0.8 mm-1.5 mm, and the contact angle of the surface after wettability treatment is between 20° and 40°. The channel width of the sparse guide channel arranged in the condensation region is 1.0 mm-1.5 mm, the spacing is greater than 2 mm, and the surface contact angle is controlled to be between 40° and 60°. By designing the microchannel structure parameters and surface wettability gradient in different regions, a working medium circulation system driven by capillary force and gravity is constructed. In the evaporation region, a narrow channel width of 0.2 mm-0.5 mm, a dense microchannel network with a small spacing of not greater than 0.5 mm, and strong wettability treatment with a contact angle of not greater than 20° are used to form a high capillary driving force and ensure that the working medium at the heat source 7 is quickly replenished. The bending transition region is provided with a flow guide groove with a medium width of 0.5 mm-1.0 mm and a spacing of 0.8 mm-1.5 mm, and a medium wettability with a contact angle of 20°-40°, which not only ensures smooth flow of condensate, but also avoids excessive capillary force hindering gravity action. The condensation region adopts a wide channel of 1.0 mm-1.5 mm and a sparse layout with a large spacing of greater than 2 mm, and a weak wettability treatment with a contact angle of 40°-60°, which reduces the capillary retention effect and promotes the condensate to quickly separate from the surface under the guidance of gravity. Through the gradient decreasing design of the contact angle from not greater than 20° to 40°-60° in the three regions, a capillary force gradient field is formed, which is superimposed with the gravity potential energy generated by the bending structure to realize the directional flow enhancement of the working medium from the condensation region to the evaporation region. The microchannel network refers to a regularly arranged channel structure formed on the surface of a metal substrate through microfabrication technology, which can be realized by laser etching or chemical etching process, and is used to enhance the capillary transport capacity of the working medium in the evaporation region. The flow guide groove refers to a continuous flow channel with a specific cross-sectional shape, which can be realized by mechanical milling or electrochemical machining, and is used to accept condensate and reduce flow resistance. The wettability surface treatment refers to forming a functional layer with specific wetting properties on the metal surface through chemical plating or physical deposition method, such as using aluminum oxide nano coating or silane coupling agent modification treatment, which is used to regulate the wetting behavior and flow direction of the working medium in the channel. The contact angle refers to the three-phase contact line angle formed by the liquid drop on the solid surface, which is realized by surface energy regulation, and is used to characterize the strength of the material wettability.

[0032] To make the flow guide groove structure of the bending transition area adapt to different installation conditions and flow requirements, and avoid the limitation of condensate backflow efficiency, in an embodiment, the flow guide groove is one of an axial groove, a spiral groove or a mesh groove. By limiting the specific structure type of the flow guide groove, the liquid flow path is optimized for different application scenarios. The axial groove extends along the axis direction and is suitable for linear bending structures that need to direct the liquid to flow quickly, which can reduce the flow resistance. The spiral groove increases the contact area of the liquid and the groove through a spiral path, which extends the flow guide path in limited space and is suitable for complex bending structures that need to distribute the liquid flow uniformly. The mesh groove forms a capillary force synergy through a multi-directional cross groove network, which is suitable for high-density heat source 7 layout scenarios that need to split or collect liquid in multiple directions. The selection of the three types of grooves can be adapted according to the actual bending angle, installation space and heat source 7 distribution characteristics, to ensure that the condensate can be effectively guided in the bending transition area and form a synergistic effect with different lyophilic surface treatments, thereby breaking through the limitation of the traditional single groove structure on the flow pattern.

[0033] It should be noted that the axial groove is suitable for linear installation scenarios with small bending angles. The parallel groove structure of the axial groove makes the condensate flow back to the evaporation section 2 along the shortest path, reducing the flow resistance. The spiral groove is suitable for complex bending structures with space limitations. The spiral trajectory increases the contact area of the liquid and the groove in limited space, strengthening the capillary driving force. The mesh groove is suitable for multi-heat source 7 distribution scenarios. The cross groove network forms a multi-directional capillary channel, allowing the condensate to autonomously select a flow path based on the heat source 7 position, avoiding local liquid accumulation.

[0034] The working principle and working process of the present application are as follows: Through physical structure innovation and surface property regulation, the synergy of gravity and capillary force is realized, and the working fluid backflow efficiency is significantly enhanced. The condensation section 3 of the uniform temperature plate is bent upwards relative to the evaporation section 2, forming an inclination angle of 8°-20°. A clear height difference is set in the direction of gravity. This bending structure not only creates a natural gravity backflow path for the condensate, but also provides directional flow guidance on the inclined surface. At the same time, according to the functional requirements of different areas inside the uniform temperature plate, microstructures with gradient lyophilic characteristics are set respectively: the evaporation area adopts a dense microchannel network and strong lyophilic treatment to maximize the capillary driving force, ensuring continuous supply of working fluid at the heat source 7; the condensation area adopts a sparse channel and weak lyophilic treatment to reduce the capillary retention effect, promoting the condensate to quickly detach under the action of gravity; the bending transition area realizes seamless connection of liquid flow through the medium lyophilic flow guide groove, forming a directional capillary and gravity synergy driving mechanism from the condensation end to the evaporation end.

[0035] Its workflow begins with the evaporation section 2 absorbs heat source 7 heat, so that the liquid phase working medium vaporization into steam. Steam under the action of pressure difference rapidly spread to the higher position of the condensation section 3, in the condensation section 3 outer surface heat dissipation fin strengthening heat release under the action of latent heat release condensation into liquid. Condensed liquid under the action of gravity first along the inclined surface of the condensation section 3, through the network of gradually changing hydrophilic flow channel convergence into the bend transition area. In the bend transition area, the liquid in the medium hydrophilic surface and specific groove structure under the guidance of continuous flow state flow to the evaporation section 2. The final liquid reaches the evaporation section 2, by strong hydrophilic microchannel network is quickly absorbed and transported to the heat source 7 core area, complete the whole cycle. This process effectively overcomes the traditional heat sink in the horizontal installation due to the lack of gravity potential energy caused by the lack of backflow power problem, realize the stable and efficient heat dissipation under the condition of high heat flux.

[0036] The above description is only the preferred embodiment of the present application, not any form of the present application, although the present application has been disclosed as above, however, not to limit the present application, any person skilled in the art, without departing from the scope of the present application, when the above disclosed technical content can make some more changes or modifications for equivalent embodiments, but as long as it does not deviate from the technical solution of the present application, according to the technical essence of the present application, any brief introduction, modification, equivalent change and modification of the above embodiment, all still belong to the scope of the present application technical solution.

Claims

1. A bend-type vapor chamber condenser end lifting structure, characterized by, The even temperature plate unit comprises an evaporation section and a condensation section, the condensation section is bent upwards relative to the evaporation section to form a bent structure, so that the condensation section is higher than the evaporation section in the direction of gravity, and the bent structure forms a height difference, so that the condensed liquid phase working medium flows back to the evaporation section along the inclined surface under the action of gravity.

2. The bend-type heat spreader condenser end lifting structure according to claim 1, characterized in that, The even temperature plate unit is a U-shaped bent structure, the U-shaped bent structure comprises two vertical sections and a horizontal section, two ends of the horizontal section are connected with the two vertical sections respectively, and the condensation section is located above the horizontal section.

3. The bend-type heat spreader condenser end lifting structure according to claim 1, characterized in that, The outer surface of the condensation section is provided with first heat dissipation fins.

4. The bend-type heat spreader condenser end lifting structure according to claim 1, characterized in that, The bending angle of the condensation section bent upwards relative to the evaporation section is between 8° and 20°.

5. The bend-type heat spreader condenser end lifting structure according to claim 2, wherein A bottom plate is arranged on the horizontal section of the U-shaped bent structure, a plurality of discrete heat sources are arranged on the bottom plate, and the evaporation section corresponds to the positions of the plurality of heat sources and covers the heat sources.

6. The bend-type heat spreader condenser end lifting structure according to claim 2, characterized in that, The even temperature plate unit is a plurality of units, and the vertical sections of adjacent even temperature plate units are attached, and second heat dissipation fins are arranged between the two vertical sections of each even temperature plate unit.

7. A method for enhancing the gravity return of a bend-type vapor chamber, based on the lifting structure of the condensing end of a bend-type vapor chamber according to any one of claims 1-6, characterized in that, The method comprises the following steps: S1: dividing the internal working chamber of the even temperature plate into an evaporation area, a bent transition area and a condensation area according to functions and spatial positions, wherein the condensation area is arranged above the evaporation area in the direction of gravity and communicates with the evaporation area through the bent transition area to form a U-shaped structure circuit; S2: arranging a dense microchannel network on the upper wall surface and the adjacent side wall area of the evaporation area opposite to the heat source, and applying a first lyophilic surface treatment to all the inner wall surfaces of the area to form the maximum capillary driving force and liquid absorption capacity for continuously supplying the required liquid phase working medium at the heat source, and arranging a weak lyophilic structure on the uncovered area of the remaining inner wall surfaces of the evaporation area to prevent liquid flow deviation; S3: arranging sparse microchannels on the top inner surface and the upper inner wall surface of the condensation area and applying a third lyophilic surface treatment to make the condensed liquid quickly separate from the condensation surface under the action of gravity and flow into the lower area, and the remaining inner wall surfaces in the area are treated with a smooth metal surface to reduce unnecessary liquid stagnation and capillary retention; S4: arranging a flow guide groove structure connected with S2 and S3 on the inner wall of the lower concave turning surface of the bent transition area, the flow guide groove is between the evaporation area and the condensation area in terms of channel width and spacing, and a second lyophilic surface treatment is applied to seamlessly receive the liquid from the condensation area and guide it to flow smoothly to the evaporation area.

8. The method of claim 7, wherein the method further comprises: The lyophilicity of the first lyophilic surface treatment, the second lyophilic surface treatment and the third lyophilic surface treatment decreases in turn.

9. The method of claim 7, wherein the method further comprises: The channel width of the microchannel network arranged in the evaporation area is 0.2mm-0.5mm, the channel spacing is not greater than 0.5mm, and the surface is treated with a hydrophilic surface having a contact angle of not greater than 20°, the channel width of the flow guide groove in the bending transition area is 0.5mm-1.0mm, the channel spacing is 0.8mm-1.5mm, the contact angle of the surface after hydrophilic treatment is between 20° and 40°, and the channel width of the sparse guide channel arranged in the condensation area is 1.0mm-1.5mm, the spacing is greater than 2mm, and the surface contact angle is controlled to be between 40° and 60°.

10. The method of claim 7, wherein the method further comprises: The flow guide groove is one of an axial groove, a spiral groove or a mesh groove.

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