A heat dissipation device

Abstract

This application relates to the field of heat dissipation technology, specifically to a heat dissipation device, comprising: a housing having a vacuum cavity inside, wherein a heat dissipation channel for circulating phase change working fluid is provided within the vacuum cavity, and the inner wall of the heat dissipation channel has a capillary structure; an active part including a first permanent magnet and a driving component, both disposed outside the housing, the driving component driving the first permanent magnet to rotate; and a driven part including a second permanent magnet and a rotating component, both disposed inside the housing, the second permanent magnet being located inside the rotating component; the first permanent magnet and the second permanent magnet are isolated by the housing, and when the first permanent magnet rotates, it drives the second permanent magnet and the rotating component to rotate through magnetic coupling, thereby driving the steam flow within the heat dissipation channel. This heat dissipation device, by actively driving the steam flow, can effectively overcome the flow resistance within complex cavities, eliminate local flow dead zones, and allow steam to rapidly diffuse from the evaporation zone to the condensation zone, thus improving the phase change cycle efficiency.

Description

Technical Field

[0001] This application relates to the field of heat dissipation technology, specifically to a heat dissipation device. Background Technology

[0002] 3DVC (3D Vapor Chamber) heat sink is the third generation of phase change heat dissipation technology after heat pipe and traditional VC. It achieves two-phase circulation heat transfer of the working fluid through an integrated, interconnected vacuum chamber and internal capillary structure. It has been applied to high heat flux density scenarios such as AI servers and 5G base stations, with a heat dissipation power consumption exceeding 1400W.

[0003] In related technologies, 3DVC is typically achieved through integrated welding, three-dimensional capillary structures, and high-vacuum encapsulation. During operation, a heat source causes the liquid working fluid to evaporate. The vapor diffuses within the cavity to the condensation zone, where it releases heat and condenses. It then flows back to the evaporation zone via capillary force.

[0004] However, due to the complex internal structure of the cavity and the tortuous vapor diffusion path, there are local flow dead zones, resulting in high flow resistance. The capillary porosity and pore size are poorly matched, leading to significant backflow lag and heavy reliance on gravity assistance. When not installed horizontally, the circulation efficiency decreases by 30% to 50%. Furthermore, vapor preferentially flows along the central path, with only 60% to 70% utilization in the cavity edge areas, resulting in high thermal resistance (0.05℃ / W to 0.1℃ / W). The maximum heat dissipation is approximately 1000W to 1400W, and it cannot dynamically adapt to load changes, making the circulation system a heat dissipation bottleneck under high loads. Simultaneously, when faced with sudden high heat flux shocks, the mismatch between the working fluid's heat capacity and circulation speed results in a transient response time greater than 1 second, causing a rapid temperature rise and easily leading to chip overheating, frequency throttling, or damage. Summary of the Invention

[0005] This application provides a heat dissipation device to solve the problems of low heat dissipation efficiency, high flow resistance and poor installation adaptability in related technologies.

[0006] This application provides a heat dissipation device, comprising: a housing having a vacuum cavity formed inside, wherein a heat dissipation channel for circulating a phase change working fluid is provided within the vacuum cavity, and the inner wall of the heat dissipation channel is provided with a capillary structure; an active part including a first permanent magnet and a driving member, both disposed outside the housing, the driving member driving the first permanent magnet to rotate; and a driven part including a second permanent magnet and a rotating member, both disposed inside the housing, the second permanent magnet being located inside the rotating member; the first permanent magnet and the second permanent magnet are isolated from each other by the housing, and when the first permanent magnet rotates, it drives the second permanent magnet and the rotating member to rotate through magnetic coupling, thereby driving the steam flow within the heat dissipation channel.

[0007] Optionally, the vacuum chamber includes: an evaporation zone for contacting a heat source, wherein the rotating component is located within the evaporation zone; and a condensation zone connected to the evaporation zone.

[0008] Optionally, the rotating component is an impeller, the second permanent magnet is embedded in the impeller, and the impeller is rotatably supported on the bottom wall of the evaporation zone.

[0009] Optionally, the inner surface of the bottom wall of the evaporation zone is provided with a settling platform, the liquid working fluid is filled in the settling platform, and the impeller is arranged at intervals above and below the settling platform.

[0010] Optionally, a clearance space is formed between the side wall of the settling platform and the vacuum chamber, and a groove is provided on the bottom wall of the evaporation zone near the clearance space; a convex ball is provided at the bottom of the impeller, and the impeller is rotatably supported in the groove through the convex ball.

[0011] Optionally, the surface of the groove and / or the convex ball is provided with a solid lubricating coating.

[0012] Optionally, the driving component is a motor disposed within the clearance space, and the output shaft of the motor is fixedly connected to the first permanent magnet; or, the driving component is a multi-phase excitation coil, and the multi-phase excitation coil is disposed around the first permanent magnet.

[0013] Optionally, the vertical distance between the first permanent magnet and the second permanent magnet is 3mm to 5mm.

[0014] Optionally, the device also includes a controller electrically connected to the drive unit, the controller having an integrated temperature sensor, and the controller being configured to selectively operate in a performance-priority mode or a power-priority mode based on at least one of the temperature sensor's detection value and the power consumption signal of the heat source chip.

[0015] Optionally, in the performance-priority mode, the controller adjusts the rotational speed of the first permanent magnet according to the power consumption signal; in the power consumption-priority mode, the controller maintains the rotational speed of the first permanent magnet at a base speed according to the detection value of the temperature sensor, and outputs a speed adjustment signal to the cooling fan.

[0016] Beneficial effects: This application provides a heat dissipation device. An active part is located on the outer side of the housing, and a driven part is located on the inner side. A driving component drives a first permanent magnet, and a second permanent magnet is located inside a rotating component. The two permanent magnets are isolated from each other by a cavity wall. When the first permanent magnet on the outer side of the housing rotates under the driving force of the driving component, the rotating magnetic field it generates penetrates the cavity wall, driving the second permanent magnet and the rotating component on the inner side of the housing to rotate synchronously in a non-contact manner. This actively drives the vapor in the vacuum cavity to flow in a predetermined direction. Compared with the passive circulation method in related technologies that relies on natural diffusion and capillary recirculation, this heat dissipation device, by actively driving the vapor flow, can effectively overcome the flow resistance in complex cavities, eliminate local flow dead zones, and allow vapor to quickly diffuse from the evaporation zone to the condensation zone, improving the phase change cycle efficiency. The rapid flow of vapor makes the vapor distribution in the cavity more uniform, avoiding the problem of low utilization of edge areas caused by vapor preferentially flowing along the center path, thereby increasing the effective heat dissipation area of ​​the entire cavity. The non-contact magnetic coupling driving method eliminates the need for a rotating shaft to pass through the housing, avoiding the leakage risk caused by dynamic sealing structures, and ensuring the cavity's sealing performance. Meanwhile, the driving components on the outside of the housing are independent of the rotating components on the inside of the housing, making installation and maintenance more convenient and ensuring high structural reliability. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a partial structural diagram of the heat dissipation device according to an embodiment of this application; Figure 2 This is a partial structural diagram of the housing and rotating component according to an embodiment of this application; Figure 3 This is a schematic diagram of the rotating component according to an embodiment of this application; Figure 4 This is a structural schematic diagram of the rotating component from another perspective of an embodiment of this application; Figure 5 This is a schematic diagram of the structure of the first permanent magnet and the driving component according to an embodiment of this application; Figure 6 for Figure 5 Sectional view along the middle AA direction; Figure 7 This is a bottom schematic diagram of the heat dissipation device according to an embodiment of this application.

[0019] Explanation of reference numerals in the attached figures: 1. Shell; 101. Vacuum chamber; 1011. Evaporation zone; 1012. Condensation zone; 102. Heat dissipation channel; 103. Heat sink; 104. Platform; 105. Clearance space; 1051. Groove; 2. First permanent magnet; 3. Drive component; 301. Rotating shaft; 4. Second permanent magnet; 5. Rotating component; 501. Blade; 502. Convex spherical part; 6. Controller. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] Reference Figures 1 to 7 As shown, this application provides a heat dissipation device, which includes a housing 1, an active part, and a driven part.

[0022] Specifically, a vacuum cavity 101 is formed inside the housing 1. The vacuum cavity 101 is provided with a heat dissipation channel 102 for the circulation of the phase change working fluid, and the inner wall of the heat dissipation channel 102 has a capillary structure. The active part is located outside the housing 1 and includes a first permanent magnet 2 and a driving member 3 for driving the first permanent magnet 2 to rotate. The driven part is located inside the housing 1 and includes a second permanent magnet 4 and a rotating member 5, wherein the second permanent magnet 4 is located inside the rotating member 5.

[0023] The first permanent magnet 2 and the second permanent magnet 4 are isolated by the wall of the housing 1, meaning they do not directly contact each other. When the driving component 3 drives the first permanent magnet 2 to rotate, the first permanent magnet 2 generates a rotating magnetic field. This rotating magnetic field penetrates the wall of the housing 1 and drives the second permanent magnet 4 to rotate through magnetic coupling. The second permanent magnet 4 then drives the rotating component 5 to rotate as well. When the rotating component 5 rotates, it can drive the steam flow within the heat dissipation channel 102.

[0024] By setting an active part on the outside of the housing 1 and a driven part on the inside of the housing 1, a driving component 3 drives a first permanent magnet 2, and a second permanent magnet 4 is located inside a rotating component 5. The two permanent magnets are isolated from each other by the cavity wall. When the first permanent magnet 2 on the outside of the housing 1 rotates under the driving action of the driving component 3, the rotating magnetic field it generates penetrates the cavity wall and drives the second permanent magnet 4 and the rotating component 5 on the inside of the housing 1 to rotate synchronously in a non-contact manner, thereby actively driving the steam in the vacuum cavity 101 to flow in a set direction. Compared with the passive circulation method that relies on natural diffusion and capillary reflux in related technologies, this heat dissipation device can effectively overcome the flow resistance in complex cavities and eliminate local flow dead zones by actively driving the steam flow, so that the steam can quickly diffuse from the evaporation zone 1011 to the condensation zone 1012, thereby improving the phase change cycle efficiency. The rapid flow of steam makes the steam distribution in the cavity more uniform, avoiding the problem of low utilization rate of the edge area caused by the steam preferentially flowing along the central path, thereby increasing the effective heat dissipation area of ​​the entire cavity. The non-contact magnetic coupling drive method eliminates the need for the rotating shaft 301 to pass through the housing 1, avoiding the leakage risk associated with dynamic sealing structures and ensuring the cavity's sealing performance. Furthermore, the drive component 3 on the outside of the housing 1 and the rotating component 5 on the inside of the housing 1 are independent of each other, making installation and maintenance more convenient and ensuring high structural reliability.

[0025] In practical applications, the shell 1 can be made of metal or a high thermal conductivity composite material. The vacuum chamber 101 is evacuated to a high vacuum state, and the phase change working fluid can be deionized water, acetone, or fluorinated liquid, etc. The heat dissipation channel 102 can be a network of pipes arranged in an array at intervals. The capillary structure can be a sintered copper powder layer, a woven mesh, or a groove structure, used to allow the condensed liquid working fluid to flow back to the evaporation part under the action of capillary force.

[0026] The heat dissipation device provided in this application is a 3DVC heat dissipation device, which is a three-dimensional two-phase heat dissipation device developed based on the traditional planar VC. Its main body is a sealed vacuum cavity 101 formed by integral welding, which is integrally connected in the X / Y / Z directions. The vacuum cavity 101 is provided with heat dissipation channels 102. Multiple heat dissipation channels 102 are arranged in an array inside the vacuum cavity 101, similar to multiple parallel heat dissipation support pipes. Adjacent heat dissipation channels 102 form uniform and spaced steam flow channels. These channels are interconnected in three-dimensional space, forming a three-dimensional network for steam diffusion. These channels can also be understood as steam flow paths inside the cavity.

[0027] The vacuum chamber 101 includes an evaporation zone 1011 and a condensation zone 1012. The evaporation zone 1011 is used to contact a heat source, such as directly contacting the surface of a high-power chip like a CPU (Central Processing Unit) or GPU (Graphics Processing Unit) to absorb heat. The condensation zone 1012 is connected to the evaporation zone 1011, and is typically located above or to the side of the evaporation zone 1011. There is no physical barrier between the two, allowing vapor to diffuse freely within the vacuum chamber 101.

[0028] Heat dissipation channel 102 can be equipped with heat sinks 103 at both the upper and lower ends. For example, the heat sinks 103 can be welded multi-layer heat dissipation fins to dissipate heat into the environment. A phase change working fluid (such as deionized water) is filled into the vacuum chamber 101. In a vacuum environment, the liquid working fluid is distributed in the capillary structure by capillary force. During operation, the evaporation zone 1011 absorbs heat from the heat source, and the liquid working fluid vaporizes into steam. The steam diffuses along the heat dissipation channel 102 towards the condensation zone 1012. After releasing its latent heat of vaporization in the condensation zone 1012, the steam condenses into liquid. The liquid working fluid then flows back to the evaporation zone 1011 along the capillary structure, completing the phase change cycle. A rotating component 5 is installed in the evaporation zone 1011 to accelerate the upward or downward flow of steam towards the condensation zone 1012 at the source of steam generation.

[0029] In specific products, the area and height of the evaporation zone 1011 can be adaptively set according to the usage scenario. For example, the size of the evaporation zone 1011 can be adjusted for chips of different sizes or different heat dissipation power requirements. Furthermore, in traditional 3DVCs, the reflux of the liquid working fluid mainly relies on capillary force and gravity. When the heat dissipation device is placed on its side (i.e., the evaporation zone 1011 and the condensation zone 1012 are arranged horizontally), the direction of gravity is perpendicular or opposite to the reflux path, resulting in a significant decrease in circulation efficiency. This solution actively drives the steam from the evaporation zone 1011 to the condensation zone 1012 through the rotating component 5, rather than passively relying on buoyancy, thereby reducing dependence on the direction of gravity. Therefore, regardless of whether the heat dissipation device is placed upright (evaporation zone 1011 below, condensation zone 1012 above) or on its side (evaporation zone 1011 and condensation zone 1012 are horizontally opposite each other), the rotating component 5 can maintain stable working fluid circulation, ensuring essentially consistent heat dissipation performance.

[0030] In one alternative implementation, refer to Figures 2 to 4As shown, the rotating component 5 can specifically take the form of an impeller. The second permanent magnet 4 is embedded inside the impeller and can be fixed by means of adhesive bonding or interference fit to ensure that there is no relative movement between the two during rotation. The impeller is rotatably supported on the bottom wall of the evaporation zone 1011. The blades 501 of the impeller can adopt a forward-curved blade design. The thickness of the blades 501 is relatively thin, which can be set to less than 0.3mm, to obtain a better gas driving effect. The twist angle of the blades 501 can be set to 20°, and the blade angle changes significantly along the radial direction, so that the impeller can drive the steam to a flow velocity of 5m / s at the rated speed. This impeller is specifically designed for driving gas, unlike impellers for driving liquids, and can effectively overcome the flow resistance of steam in complex three-dimensional channels.

[0031] Specifically, a recessed platform 104 can be provided on the inner surface of the bottom wall of the evaporation zone 1011. The platform 104 is a downwardly recessed structure, and the liquid working fluid fills the platform 104 under the action of gravity or capillary force, and the liquid working fluid is only contained within the platform 104. The impeller is arranged vertically and horizontally above the platform 104, that is, the impeller is located above the platform 104 and does not directly contact the liquid working fluid, but is suspended in the steam space above the platform 104. This arrangement ensures that when the impeller rotates, it mainly drives the steam flow without agitating the liquid working fluid at the bottom, thus avoiding interference from liquid splashing on the steam flow. The depth of the platform 104 can be determined according to the amount of liquid working fluid filled, usually ensuring that a certain amount of liquid working fluid is always present in the platform 104 under any working posture to prevent the evaporation zone 1011 from drying out.

[0032] Furthermore, a clearance space 105 is formed between the side wall of the settling platform 104 and the inner wall of the vacuum chamber 101, which is used to accommodate the drive component 3 or other components. A groove 1051 is provided on the bottom wall of the evaporation zone 1011 near the clearance space 105. This groove 1051 supports the impeller, and its depth can be set to less than 1 mm. A convex ball portion 502 is provided at the bottom of the impeller, which mates with the groove 1051, allowing the impeller to be rotatably supported within the groove 1051 via the convex ball portion 502. The bottom of the groove 1051 can be designed as a spherical or conical surface to form point or line contact with the convex ball portion 502, reducing frictional resistance during rotation.

[0033] This mating structure of the groove 1051 and the convex ball 502 eliminates the need for a traditional shaft hole structure. During the operation of the heat dissipation device, the bottom of the housing 1 will experience thermal expansion due to heat. The shaft hole mating is prone to jamming due to changes in radial clearance during thermal deformation. However, the convex ball 502 can deflect and slide slightly within the groove 1051, automatically adapting to the relative positional changes caused by thermal deformation, thus reducing the risk of jamming. Furthermore, the mating of the groove 1051 and the convex ball 502 requires lower machining precision, eliminating the need for strict control of cylindricity and coaxiality as required by shaft hole mating, which helps reduce manufacturing costs. Moreover, this structure eliminates the need to machine a shaft hole that penetrates the cavity wall, avoiding the sealing problems caused by the rotating shaft 301 passing through the cavity, reducing potential leakage points, and improving the long-term reliability of the vacuum cavity 101.

[0034] In one optional embodiment, the surfaces of the groove 1051 and the convex ball 502 may be coated with a solid lubricating coating, or the solid lubricating coating may be applied to only one of their surfaces. This coating possesses wear resistance and low frictional resistance, enabling the impeller to maintain low frictional loss when rotating at high speed under magnetic force. The coating material can be selected from polytetrafluoroethylene (PTFE), sputtered molybdenum disulfide (MoS2), or diamond-like carbon (DLC). The coefficient of friction for PTFE coatings is approximately 0.08, for molybdenum disulfide coatings it is approximately 0.04, and for DLC coatings it is approximately 0.05. In practical applications, the appropriate material can be selected based on requirements and performance specifications; for example, PTFE coatings can be chosen for applications with cost constraints, while DLC coatings can be chosen for applications requiring high wear resistance.

[0035] In one alternative implementation, refer to Figure 5 and Figure 6 As shown, the driving component 3 can be a motor, which is located in the clearance space 105, specifically in the gap between the side wall of the platform 104 and the inner wall of the vacuum chamber 101, and outside the housing 1. The motor is positioned here because the clearance space 105 is originally an unused area between the platform 104 and the chamber; utilizing this space to accommodate the motor eliminates the need for additional heat dissipation device thickness, resulting in a compact structure. The motor's output shaft is fixedly connected to the first permanent magnet 2. When the motor is powered on, the output shaft drives the first permanent magnet 2 to rotate. The first permanent magnet 2 and the second permanent magnet 4 inside the chamber are separated by the bottom wall of the housing 1, and there is no direct contact between them. The rotating first permanent magnet 2 generates a changing magnetic field, which penetrates the metal cavity wall, driving the second permanent magnet 4 and the impeller to rotate synchronously.

[0036] In other words, the motor and rotating parts are entirely located outside the housing 1, eliminating the need for holes in the walls of the housing 1 for the shaft 301 to pass through. This completely avoids the dynamic sealing problem between the shaft 301 and the housing 1 in traditional designs. Without dynamic sealing points, leakage failure due to aging of the sealing rings after long-term use is prevented, ensuring the airtightness of the vacuum chamber 101 is maintained for a long time and significantly extending the service life of the heat dissipation device. Simultaneously, the motor is placed within the clearance space 105, without occupying additional installation height, facilitating the integration of the heat dissipation device into space-constrained equipment such as servers. Furthermore, the motor, impeller, and other components are all installed in a detachable manner, for example, by screws or clips to the housing 1. This allows for individual replacement of faulty components during production assembly and subsequent maintenance, eliminating the need for complete scrapping and reducing maintenance costs.

[0037] In one specific embodiment, an impeller is provided on each side of the settling platform 104 in the evaporation zone 1011, with the two impellers arranged opposite each other. Each impeller has a second permanent magnet 4 embedded inside, and each impeller has a convex ball 502 at its bottom, supported in its corresponding groove 1051. Corresponding to the two impellers, two motors are provided in the clearance space 105. The output shaft of each motor is fixedly connected to a first permanent magnet 2, and the positions of the two first permanent magnets 2 are vertically aligned with the two second permanent magnets 4. The two motors can be controlled independently or operate synchronously. During operation, the two motors drive their respective first permanent magnets 2 to rotate, causing the two impellers to rotate simultaneously through magnetic coupling. The two impellers are located on opposite sides of the settling platform 104, and their rotation directions can be set to opposite directions, thus causing the steam in the evaporation zone 1011 to flow from the center to both sides, or from both sides to the center, depending on the rotation direction of the impeller blades 501. This double-sided impeller arrangement allows steam to be more evenly diffused to all parts of the condensation zone 1012, avoiding steam flow deviation that may be caused by a single-sided impeller, further improving the utilization rate of the edge area of ​​the evaporation zone 1011, and increasing the effective heat dissipation area from 60% to 70% to over 90%.

[0038] In one optional embodiment, a top wall is provided above the platform 104, which separates the platform 104 from the condensation zone 1012 above it. Multiple through holes are formed on the top wall, and these through holes are evenly distributed along the plane of the top wall. Heat sinks 103 are disposed on the outer wall of the vacuum chamber 101, and heat dissipation channels 102 are disposed inside the vacuum chamber 101, located in the area between the top wall and the inner top wall of the vacuum chamber 101. When the liquid working fluid in the platform 104 is heated, it vaporizes into steam. The steam flows upward, passes through the through holes on the top wall, enters the heat dissipation channel 102, and continues to diffuse upward into the condensation zone 1012. Upon contact with the cooler wall surface, it releases heat and condenses into liquid, then flows back to the platform 104 along the capillary structure. This structure with through holes in the top wall allows steam to flow upwards from multiple channels above the platform 104, forming a directional steam flow and preventing disorderly diffusion of steam in the large space between the platform 104 and the top wall. On the other hand, the presence of through holes has a certain throttling effect on steam flow, which can appropriately increase the steam flow rate and facilitate the rapid entry of steam into the far end area of ​​the heat dissipation channel 102, thus improving the uniformity of heat dissipation.

[0039] In another embodiment, the driving component 3 can also be a multiphase excitation coil. The multiphase excitation coil is arranged around the first permanent magnet 2. By applying multiphase alternating current with phase differences in time, a time-varying magnetomotive force is generated in multiple coils arranged at a certain angle in space. These magnetomotive force vectors are superimposed in space to synthesize a magnetic field with a constant amplitude and an angular velocity synchronized with the power supply frequency, continuously rotating in space, thereby driving the first permanent magnet 2 to rotate. By adjusting the frequency, amplitude, and phase of the excitation current, the speed, intensity, and direction of the rotating magnetic field can be independently controlled. The driving method in the above two embodiments can be selected according to actual design requirements. The motor-based implementation has a simple structure and is easy to control, while the multiphase excitation coil implementation has no moving parts and higher reliability.

[0040] Optionally, the wall thickness of the housing 1 can be 1mm, and the vertical distance between the first permanent magnet 2 and the second permanent magnet 4 can be 3mm to 5mm. This distance refers to the vertical distance between the surface of the first permanent magnet 2 closest to the housing 1 and the surface of the second permanent magnet 4 closest to the housing 1, i.e., the gap between them. The size of this gap directly affects the strength of the magnetic coupling: if the gap is too small, although the coupling strength is high, the assembly precision requirements are stringent, and the magnets may collide due to deformation of the housing 1; if the gap is too large, the coupling strength decreases, which may cause the impeller to be unable to be effectively driven. The range of 3mm to 5mm is obtained through optimization based on taking into account both coupling efficiency and assembly tolerance, which can ensure that the first permanent magnet 2 can reliably drive the second permanent magnet 4 to rotate under various working conditions.

[0041] In one alternative implementation, refer to Figure 7 As shown, the heat dissipation device also includes a controller 6. The controller 6 is electrically connected to the drive unit 3 and is used to control the operation of the drive unit 3. The controller 6 integrates a temperature sensor, which can read the temperature at the bottom of the evaporation zone 1011 in real time, or read the temperature at the location in contact with the heat source chip. The controller 6 is configured to selectively operate in a performance-priority mode or a power-priority mode based on at least one of the detected value of the temperature sensor and the power consumption signal of the heat source chip.

[0042] Specifically, the controller 6 can have a pre-set control program, which can be a functional relationship obtained through testing before the heat dissipation device leaves the factory. For example, it can be the correspondence between chip power consumption, motor speed (or power frequency of the excitation coil), and ambient temperature. The controller 6 reads the temperature sensor and chip power consumption information, calls the functional relationship, and outputs the corresponding current or frequency signal to the drive unit 3, thereby adjusting the rotational speed of the first permanent magnet 2.

[0043] In one optional implementation, in performance-priority mode, the controller 6 adjusts the rotational speed of the first permanent magnet 2 based on the power consumption signal. Specifically, the controller 6 reads the temperature signal from the temperature sensor and the power consumption information of the chip in real time. When the controller 6 detects an increase in the chip's power consumption, it immediately sends a signal to increase the output current or increase the excitation frequency, thereby increasing the rotational speed of the first permanent magnet 2 and thus accelerating the impeller in advance. This feedforward control method allows the impeller to increase its rotational speed before the chip temperature actually rises, thereby enhancing heat dissipation capacity in advance and effectively suppressing temperature spikes.

[0044] In a simulation experiment, the ambient temperature was set to 35°C. Under this condition, taking a total card power consumption of 1203W as an example, calculations using thermal simulation software showed that the heat dissipation device of this application, compared to a conventional 3DVC heat dissipation device without an impeller, reduced the chip junction temperature from 90.4°C to 85.3°C, a reduction of 5.1°C. At the same ambient temperature and power consumption, the thermal resistance of a conventional 3DVC heatsink is 0.0291 K / W, while the thermal resistance of the heat dissipation device of this application is 0.0246 K / W, a significant reduction of 15.5%.

[0045] In one optional implementation, in power-priority mode, the controller 6 maintains the rotational speed of the first permanent magnet 2 at a base speed based on the temperature sensor readings and outputs a speed adjustment signal to the cooling fan. Specifically, the controller 6 reads the temperature value from the temperature sensor in real time and outputs current to the drive unit 3, causing the motor to operate at a base speed that ensures the chip temperature does not exceed a safe threshold. At this time, since the impeller provides additional steam circulation power, the thermal resistance of the entire cooling system is reduced, thus allowing for a suitable reduction in the fan speed in the server rack, thereby reducing the power consumed by the fans. Because the power of the server fan is much greater than the power of the controller 6 and the motor, the energy-saving effect is significant.

[0046] Taking a certain type of server as an example, it uses 15 industrial fans with a rated power of 80W each to provide airflow, with a total fan power of 1200W. When this server adopts the heat dissipation device of this application, the power consumption of the server fans can be reduced by 20% to achieve the same cooling effect, that is, the power saving per server is 240W. The controller 6, motor, or excitation coil in the heat dissipation device of this application each require an additional 5W of power consumption. A server typically houses 8 computing cards, corresponding to 8 heat dissipation devices, totaling an additional 40W of power consumption. In summary, each server can achieve a net power saving of 200W, and assuming 6 servers per rack, each rack can save 1200W of power consumption. The speed adjustment signal output by the controller 6 to the cooling fan can be a voltage signal, used to instruct the fan drive circuit to reduce the fan speed.

[0047] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and all such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A heat dissipation device, characterized in that, include: The shell (1) has a vacuum cavity (101) inside, and the vacuum cavity (101) is provided with a heat dissipation channel (102) for circulating phase change working fluid. The inner wall of the heat dissipation channel (102) is provided with a capillary structure. The active part, including a first permanent magnet (2) and a driving member (3), is disposed outside the housing (1). The driving member (3) is used to drive the first permanent magnet (2) to rotate. The driven part, including a second permanent magnet (4) and a rotating part (5), is disposed in the housing (1), and the second permanent magnet (4) is located in the rotating part (5); The first permanent magnet (2) and the second permanent magnet (4) are isolated by the housing (1). When the first permanent magnet (2) rotates, it drives the second permanent magnet (4) and the rotating part (5) to rotate through magnetic coupling, so as to drive the steam flow in the heat dissipation channel (102).

2. The heat dissipation device according to claim 1, characterized in that, The vacuum cavity (101) includes: An evaporation zone (1011) is used to contact a heat source, and the rotating component (5) is located within the evaporation zone (1011); The condensation zone (1012) is connected to the evaporation zone (1011).

3. The heat dissipation device according to claim 2, characterized in that, The rotating component (5) is an impeller, and the second permanent magnet (4) is embedded in the impeller. The impeller is rotatably supported on the bottom wall of the evaporation zone (1011).

4. The heat dissipation device according to claim 3, characterized in that, The bottom wall inner surface of the evaporation zone (1011) is provided with a settling platform (104), and the liquid working fluid fills the settling platform (104). The impeller and the settling platform (104) are arranged vertically at intervals.

5. The heat dissipation device according to claim 4, characterized in that, A clearance space (105) is formed between the side wall of the settling platform (104) and the vacuum cavity (101), and a groove (1051) is provided on the bottom wall of the evaporation zone (1011) near the clearance space (105). The bottom of the impeller is provided with a convex ball portion (502), and the impeller is rotatably supported in the groove (1051) through the convex ball portion (502).

6. The heat dissipation device according to claim 5, characterized in that, The surfaces of the groove (1051) and / or the convex ball (502) are provided with a solid lubricating coating.

7. The heat dissipation device according to claim 5, characterized in that, The driving component (3) is a motor disposed within the clearance space (105), and the output shaft of the motor is fixedly connected to the first permanent magnet (2); or, The driving component (3) is a multiphase excitation coil, which is arranged around the first permanent magnet (2).

8. The heat dissipation device according to any one of claims 1 to 7, characterized in that, The vertical distance between the first permanent magnet (2) and the second permanent magnet (4) is 3mm to 5mm.

9. The heat dissipation device according to claim 8, characterized in that, It also includes a controller (6) electrically connected to the drive unit (3), the controller (6) having an integrated temperature sensor, the controller (6) being configured to selectively operate in a performance-priority mode or a power-priority mode based on at least one of the detection value of the temperature sensor and the power consumption signal of the heat source chip.

10. The heat dissipation device according to claim 9, characterized in that, In the performance priority mode, the controller (6) adjusts the rotational speed of the first permanent magnet (2) according to the power consumption signal; In the power consumption priority mode, the controller (6) maintains the rotation speed of the first permanent magnet (2) at the base speed according to the detection value of the temperature sensor, and outputs a speed adjustment signal to the cooling fan.

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