Heat dissipation device and electronic equipment

Abstract

The present invention provides a heat dissipation device, including a microchannel evaporator, a condenser, a micro pump, a regenerator and a pipeline; the outlet pipe of the microchannel evaporator is connected to the condenser through the pipeline, the condenser is connected to the micro pump through the pipeline, the micro pump is connected to the first end of the regenerator through the pipeline, the second end of the regenerator is connected to the outlet pipe of the microchannel evaporator through the pipeline, and the first end of the regenerator is also connected to the inlet pipe of the microchannel evaporator through the pipeline. The present invention also provides an electronic device. The heat dissipation device and electronic device provided by the present invention can meet the heat dissipation requirements of a heat source with high heat flux density in a narrow space, and have high heat dissipation efficiency.

Description

[Technical field]

[0001] The present invention relates to the field of heat dissipation technology, and in particular to a heat dissipation device and electronic equipment. [Background technology]

[0002] The rapid development of the integrated circuit and semiconductor industries has driven processing chips to move towards high performance and high integration, which has brought about the continuous increase in power density and the increasing prominence of the power consumption wall problem. Taking a common high-performance notebook as an example, the heat generated by high-power heat source chips such as the CPU (Central Processing Unit) and GPU (Graphics Processing Unit) is more than 100W. If the generated heat is not discharged in time, the chip will automatically limit its performance due to the power consumption wall to reduce the heat and avoid affecting the user experience. In severe cases, the chip will be damaged or even cause a fire due to long-term high-temperature operation.

[0003] At present, the heat dissipation of high-density heat sources is mainly a combination of forced air cooling and two-phase liquid cooling. Taking laptops as an example, most of them use multiple heat pipes or large-area liquid cooling plates plus end air cooling for heat dissipation. However, even if two-phase liquid cooling is used, it is difficult to meet the heat dissipation needs of higher power consumption chips or thinner electronic devices because evaporation and condensation use the same heat dissipation circuit and the heat dissipation space is limited. Therefore, split water cooling devices are available on the market, which use direct liquid water cooling. The heat dissipation cold end is independent of the outside of the device, and the high-temperature liquid is cooled by a large air cooling device. However, for split water cooling solutions, the heat dissipation volume is large and difficult to carry, which is not suitable for efficient heat dissipation of mobile devices. In addition, most of them use single-phase liquid cooling, and the heat dissipation efficiency is not high.

[0004] In view of this, it is necessary to provide a new type of heat dissipation device and electronic equipment to overcome the above defects. [Summary of the invention]

[0005] The purpose of the present invention is to provide a heat dissipation device and an electronic device, which can meet the heat dissipation demand of a heat source with high heat flux density in a narrow space and have high heat dissipation efficiency.

[0006] To achieve the above-mentioned objectives, in a first aspect, the present invention provides a heat dissipation device, comprising a microchannel evaporator, a condenser, a micro pump, a regenerator and a pipeline; the outlet pipe of the microchannel evaporator is connected to the condenser through the pipeline, the condenser is connected to the micro pump through the pipeline, the micro pump is connected to the first end of the regenerator through the pipeline, the second end of the regenerator is connected to the outlet pipe of the microchannel evaporator through the pipeline, and the first end of the regenerator is also connected to the inlet pipe of the microchannel evaporator through the pipeline.

[0007] In a preferred embodiment, it further comprises a liquid storage tank and a heating base, wherein the heating base carries the liquid storage tank, the heating base is connected to the condenser via the pipeline, and the liquid storage tank is connected to the micro pump via the pipeline.

[0008] In a preferred embodiment, the microchannel evaporator includes a cover plate and an evaporator body, the cover plate is arranged on the evaporator body, the inlet pipe is connected to one end of the evaporator body, and the outlet pipe is connected to the other end of the evaporator body; the evaporator body includes a plurality of microchannel tubes arranged in parallel, and one end of the microchannel tube close to the inlet pipe is connected to a plurality of throttling grooves connected in series.

[0009] In a preferred embodiment, a buffer structure is provided between the microchannel tube and the inlet tube, and the buffer structure is also provided between the microchannel tube and the outlet tube.

[0010] In a preferred embodiment, when the pipeline is filled with liquid, the liquid storage tank contains liquid working fluid that accounts for 30% to 60% of the total volume of the liquid storage tank.

[0011] In a preferred embodiment, the condenser includes a first heat dissipation rib, a first cooling fan paired with the first heat dissipation rib, a second heat dissipation rib, and a second cooling fan paired with the second heat dissipation rib; the heating base includes a U-shaped pipe, a first open end of the U-shaped pipe is connected to the pipe between the first heat dissipation rib and the second heat dissipation rib through a flow regulating valve, and a second open end of the U-shaped pipe is connected to the pipe between the first heat dissipation rib and the second heat dissipation rib.

[0012] In a preferred embodiment, a first pressure transmitter and a temperature probe are provided on the pipeline between the second heat dissipation fin and the micro pump.

[0013] In a preferred embodiment, there are multiple microchannel evaporators, and the multiple microchannel evaporators are connected in parallel.

[0014] In a second aspect, the present invention further provides an electronic device, comprising a heat source chip and a heat dissipation device as described above, wherein a microchannel evaporator in the heat dissipation device is fixed on the heat source chip, and a thermal interface layer is arranged between the microchannel evaporator and the heat source chip.

[0015] In a preferred embodiment, it further comprises a circuit board, the heat source chip is arranged on the circuit board, and the microchannel evaporator of the heat dissipation device comprises a fixing bar, and the fixing bar is fixed to the circuit board by bolts.

[0016] Compared with the prior art, the heat dissipation device and electronic equipment provided by the present invention adopt a micro pump as the circulation power of a two-phase liquid-cooled heat dissipation circuit, which greatly improves the heat dissipation capacity and has a strong ability to resist external disturbances; the microchannel evaporator has a small volume and a high relative area, which can meet the heat dissipation requirements of a high heat flux density heat source in a narrow space, and a throttling groove is provided at the channel inlet of the microchannel tube, which can play the role of a throttling valve, improve the boiling stability, and can also spontaneously generate microbubbles by isenthalpic throttling and pressure reduction, thereby enhancing the boiling heat exchange effect; the parallel connection of multiple evaporators can meet the heat dissipation requirements of distributed heat sources, and at the same time, a liquid storage tank is used for temperature control and pressure regulation, and a heat regenerator is used for heat recovery of the working fluid at the inlet and outlet of the evaporator, which can control the heat exchange state of the heat dissipation circuit, and optimize the heat exchange efficiency to the greatest extent while meeting the heat dissipation requirements, so as to achieve the minimum pump labor expenditure in exchange for the maximum heat dissipation benefit.

[0017] In order to make the above-mentioned objects, features and advantages of the invention more obvious and easy to understand, the preferred embodiments of the present invention are specifically cited below and described in detail with reference to the attached drawings.

Brief Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A block diagram of the heat dissipation device provided by the present invention;

[0020] Figure 2 A structural diagram of a microchannel evaporator of a heat dissipation device provided by the present invention;

[0021] Figure 3 for Figure 2 The enlarged view of point A in the middle;

[0022] Figure 4 A three-dimensional diagram of a microchannel evaporator of a heat dissipation device provided by the present invention;

[0023] Figure 5 A structural diagram of a liquid storage tank and a heating base of a microchannel evaporator of a heat dissipation device provided by the present invention;

[0024] Figure 6 A pressure-enthalpy principle diagram of a heat dissipation circuit of a heat dissipation device provided by the present invention;

[0025] Figure 7 This is a structural diagram of the electronic device provided by the present invention. [Specific implementation method]

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

[0027] See also Figure 1 The present invention provides a heat dissipation device 100, including a microchannel evaporator 10, a condenser 20, a micro pump 30, a regenerator 40 and a pipeline 101.

[0028] The outlet pipe 11 of the microchannel evaporator 10 is connected to the condenser 20 through the pipe 101, the condenser 20 is connected to the micro pump 30 through the pipe 101, the micro pump 30 is connected to the first end of the regenerator 40 through the pipe 101, the second end of the regenerator 40 is connected to the outlet pipe 11 of the microchannel evaporator 10 through the pipe 101, and the first end of the regenerator 40 is also connected to the inlet pipe 12 of the microchannel evaporator 10 through the pipe 101. Specifically, the pipe 101 is used to connect the entire device, and the pipe 101 of the entire cycle can be made of stainless steel metal or alloy to ensure the sealing and reliability of the connection. For ease of understanding, Figure 1 The pipeline 101 with a dotted line indicates that there is a two-phase working medium in the pipeline, and the pipeline 101 with a solid line indicates that there is a liquid working medium in the pipeline. The arrow indicates the flow direction of the working medium.

[0029] Please also read Figure 2The microchannel evaporator 10 includes a cover plate 13 and an evaporator body 14. The cover plate 13 is covered on the evaporator body 14. The inlet pipe 12 is connected to one end of the evaporator body 14, and the outlet pipe 11 is connected to the other end of the evaporator body 14. It can be understood that the working fluid can flow into the evaporator body 14 from the inlet pipe 12 and flow out through the outlet pipe 11. Specifically, a second pressure transmitter K2 is also provided on the pipe 101 close to the inlet pipe 12, and a filling port 102 is also provided on the pipe 101 between the first end of the regenerator 40 and the inlet pipe 12 of the microchannel evaporator 10. The microchannel evaporator 10 is made of a high thermal conductivity metal, such as aluminum or copper, which can minimize the temperature gradient between the evaporator and the heat source. In actual application, when there are multiple heat source chips, the number of microchannel evaporators 10 is multiple, and the multiple microchannel evaporators 10 are connected in parallel, that is, the inlet pipes of the multiple microchannel evaporators 10 are connected to each other, and the outlet pipes of the multiple microchannel evaporators 10 are connected to each other. The parallel connection of multiple evaporators can meet the heat dissipation requirements of distributed heat sources.

[0030] Furthermore, the evaporator body 14 includes a plurality of microchannel tubes 141 arranged in parallel. Specifically, the microchannel tube 141 is the core structure of heat dissipation, has an ultra-high specific surface area, and has broad application prospects in the field of efficient heat dissipation in a limited space. And the processing technology requirements are not high, which is suitable for commercial development. The cross-section of the microchannel tube 141 can be a regular geometric shape such as a rectangle or a triangle to facilitate processing and manufacturing. In this embodiment, the cross-section of the microchannel tube 141 is a rectangle, and the microchannel tube 141 is a narrow and high channel tube.

[0031] The size of the microchannel tube 141 can be adjusted according to the heat dissipation space. In this embodiment, the design parameters of the microchannel tube 141 should satisfy the constraint number Co>0.5. The Co number can be used to determine the scale of the evaporator, which is defined as:

[0032]

[0033] Among them, σ is the surface tension of the circulating medium, g is the acceleration of gravity, ρl is the density of the liquid medium, ρg is the density of the gaseous medium, and Di is the hydraulic diameter of the channel. When Co>0.5, it is believed that the heat transfer and flow of the channel are significantly different from those of the large channel, and it belongs to the category of microchannel, which can achieve efficient heat dissipation.

[0034] Please also read Figure 3, one end of the microchannel tube 141 near the inlet tube 12 is connected with a plurality of throttling grooves 142 in series, specifically, the throttling grooves 142 are rectangular, and two adjacent throttling grooves 142 and the throttling grooves 142 and the microchannel tube 141 are connected through grooves 1421. It can be understood that each throttling groove 142 forms a U-shaped structure, and the plurality of U-shaped structures can provide a large pressure loss to achieve the effect of a throttling valve, which can increase the stability of the boiling of the working medium and suppress the reflux oscillation caused by the local gas expansion on the one hand, and can throttle and reduce the pressure of the working medium on the other hand, spontaneously generate microbubbles, so that the working medium after entering the channel is directly in a two-phase flow heat exchange state, and its heat exchange efficiency is much higher than that of a single-phase heat exchange.

[0035] Furthermore, a buffer structure 143 is provided between the microchannel tube 141 and the inlet tube 12, and a buffer structure 143 is also provided between the microchannel tube 141 and the outlet tube 11. Specifically, the buffer structure 143 is an arc-shaped plate. When the cover plate 13 is covered on the evaporator body 14, a buffer space is formed between the cover plate 13 and the buffer structure 143, which can play an effective role in buffering and equalizing flow, ensuring that the working fluid of each channel is in a similar heat exchange state, and improving the temperature uniformity of the evaporator in the horizontal direction.

[0036] Please also read Figure 4 The cover plate 13 is welded to the evaporator body 14 or directly injection molded. Under the premise of meeting the mechanical strength, the thickness of the evaporator body 14 should be made as thin as possible to reduce the temperature difference between the top and bottom surfaces of the microchannel tube 141. In this embodiment, the evaporator body 14 is in the shape of a flat rectangular body. Correspondingly, the inlet pipe 12 and the outlet pipe 13 are also pressed into a flat shape, and then transition into a round tube after a section of arc tube 15 for equal flow. It can be understood that the diameter of the round tube is determined according to the circulation flow rate and the economic flow rate. In order to facilitate installation, the microchannel evaporator 10 also includes a fixing bar 103, which is formed by extending from the four corners of the microchannel evaporator 10, and the fixing bar 103 is fixed to the circuit board on which the heat source chip is installed by bolts.

[0037] The condenser 20 can be air-cooled or water-cooled. In this embodiment, the condenser 20 includes a first heat dissipation rib 21, a first cooling fan 22 paired with the first heat dissipation rib 21, a second heat dissipation rib 23, and a second cooling fan 24 paired with the second heat dissipation rib 23. The first heat dissipation rib 21 and the second heat dissipation rib 23 are formed integrally with the pipe 101 using a high thermal conductivity metal such as aluminum or copper, and are paired with the first cooling fan 22 and the second cooling fan 24, respectively. A corresponding heat dissipation unit body is set according to the requirements of the cold end. The first cooling fan 22 and the second cooling fan 24 can use a turbo centrifugal fan or an axial flow fan according to the space limitation of the condensation end.

[0038] Specifically, a first pressure transmitter K1 and a temperature probe T are provided on the pipe 101 between the second heat dissipation fin 23 and the micro pump 30 . The first pressure transmitter K1 and the temperature probe T are used to monitor the state of the condensed reflux working fluid and transmit the signal to the temperature control chip.

[0039] The micro pump 30 is the heart of the entire device's circulation loop, and is used to provide circulation power for the loop. A micro mechanical pump or a piezoelectric ceramic pump may be used. The micro pump 30 can provide a forced driving force, and the circulation power is several orders of magnitude higher than the capillary force of existing heat pipes, and the corresponding heat dissipation capacity is also greatly improved.

[0040] The purpose of the regenerator 40 is to transfer part of the heat of the high-temperature working medium at the outlet of the microchannel evaporator 10 to the low-temperature working medium at the inlet of the microchannel evaporator 10. Specifically, the second end of the regenerator 40 is connected to the outlet pipe 11 of the microchannel evaporator 10 through the flow regulating valve P, and the regenerator heat is adjusted by the flow regulating valve P to ensure that the inlet working medium is as close to the saturated state as possible, thereby reducing the supercooling of the inlet working medium of the microchannel evaporator 10. It can be understood that the regenerator 40 only exchanges the heat of the inlet and outlet fluids of the microchannel evaporator 10, and does not exchange working medium.

[0041] The heat dissipation device 100 provided by the present invention further includes a liquid storage tank 50 and a heating base 60. The heating base 60 is used to support the liquid storage tank 50. The heating base 60 is connected to the condenser 20 through a pipeline 101, and the liquid storage tank 50 is connected to the micro pump 30 through the pipeline.

[0042] Please also read Figure 5 The liquid storage tank 50 is used to store excess working fluid. On the one hand, it can accommodate the expanded working fluid to ensure the relative stability of the system pressure. On the other hand, it can control the pressure of the liquid storage tank to regulate the operating state of the system, balance the system pressure, and accommodate or supplement the liquid working fluid to ensure the safety of the system operation. The shape of the liquid storage tank 50 can be diverse. The design of the volume of the liquid storage tank 50 should be considered together with the filling amount of the working fluid. The filling amount of the system working fluid should follow the following basic principles: ensure that there is still liquid remaining in the liquid storage tank under the condition that the pipeline 101 is all liquid to ensure its gas-liquid two-phase state, and ensure that the liquid storage tank can accommodate all the working fluid when the pipeline 101 is all gas, and there is a certain amount of gas to ensure that the working fluid temperature is the saturation temperature. Comprehensively considered, in order to improve the accuracy and thermal inertia of the temperature control of the liquid storage tank, it should be ensured that when the pipeline 101 is all liquid, the liquid storage tank contains about 30% to 60% of the total volume of liquid working fluid. Furthermore, the liquid storage tank 50 is connected to the circulation loop through a single pipeline, thereby reducing the intensity of the working medium exchange between the liquid storage tank 50 and the loop, and improving the temperature control performance of the liquid storage tank 50.

[0043] The heating base 60 is used to control the temperature of the liquid storage tank 50, thereby adjusting the system pressure and further controlling the state of the condensation reflux of the working fluid. Specifically, the heating base 60 includes a U-shaped pipe, the first open end 61 of the U-shaped pipe is connected to the pipe 101 between the first heat dissipation rib 21 and the second heat dissipation rib 22 through the flow regulating valve P, and the second open end 62 of the U-shaped pipe is connected to the pipe between the first heat dissipation rib 21 and the second heat dissipation rib 22. The U-shaped pipe is used to circulate a relatively high-temperature two-phase working fluid, transferring the heat of the working fluid to the liquid storage tank 50 to increase the temperature of the liquid storage tank 50, and the corresponding pressure in the liquid storage tank 50 increases, thereby increasing the overall pressure of the system to cope with the phenomenon of gas carrying in the reflux working fluid caused by poor heat dissipation conditions at the cold end and insufficient heat dissipation.

[0044] The heat dissipation device 100 provided by the present invention adopts a liquid filling method similar to the vacuum filling of heat pipes. The working fluid is selected according to the use scenario and the pressure bearing capacity of the pipeline 101. Ultrapure water, ethanol, acetone, etc. can be conventionally used. If the intensity of boiling heat exchange needs to be further enhanced, some nano copper oxide particles can be doped. It can be understood that the signals of each pressure transmitter, temperature probe, speed adjustment of the micro pump, opening of the electric flow control valve, speed of the cooling fan, etc. are transmitted to the temperature control chip for unified control.

[0045] Combine the following Figure 6 The principle of the heat dissipation device 100 provided by the present invention is described in detail:

[0046] The supercooled liquid (state point 6) from the heat dissipation cold end (i.e., condenser 20) increases in pressure (state point 1) under the driving action of the micro pump 30, and exchanges heat with the high-temperature working medium of the outlet pipe 11 of the microchannel evaporator 10 through the regenerator 40 to a state close to saturation (state point 2); in the throttling groove 142 near the inlet pipe 12, the throttling and pressure reduction effect of the U-shaped resistance component is utilized, so that the nearly saturated liquid is in the gas-liquid two-phase region (state point 3) when entering the expansion section after undergoing an isenthalpic pressure reduction process, and then spontaneously generates microbubbles, and complex boiling phase change heat transfer and two-phase flow processes occur in the expansion section, taking away the heat transferred from the high-temperature heat source chip to the microchannel tube 141; the generated gas-liquid two-phase fluid (state point 4) passes through the pipeline 101 and the regenerator 40 to the heat dissipation cold end, and the steam is condensed into a supercooled liquid (state point 5) through the air cooling heat dissipation effect.

[0047] Furthermore, when the ambient temperature rises and the cooling fan power reaches the maximum, the supercooling of the working fluid cannot reach the set value or the fluid entering the micro pump 30 is in the two-phase region, the flow regulating valve connected to the liquid storage tank 50 and the heating base 60 is opened, so that the high-temperature working fluid flows into the heating base 60, the liquid storage tank 50 is heated to increase the back pressure of the system, the saturation temperature of the corresponding working fluid is increased, the heat dissipation capacity of the cold end is enhanced, and the opening of the valve is dynamically adjusted according to the supercooling. The supercooled liquid coming out of the heat dissipation cold end is heated and reduced in pressure through the pipeline 101 and arrives at the suction port (state point 6) of the micro pump 30. It is necessary to ensure that the supercooling of the working fluid at this location is greater than a certain value to avoid cavitation in the micro pump 30. The supercooling is determined according to the supercooling of the state point 5 and the characteristics of the circulation loop. Therefore, the pump-driven microchannel two-phase flow loop of the heat dissipation device 100 provided by the present invention is an adaptive and efficient heat dissipation system. By monitoring the fluid state at each point in the system, the flow rate of the micropump 30, the opening of the flow regulating valves of the heat regenerator 40, the liquid storage tank 50 and the heating base 60 are actively regulated, so that the working fluid in the microchannel tube 141 maintains an efficient boiling heat transfer state, effectively controlling the temperature of the heat source chip within the design range, and obtaining the maximum heat dissipation benefit with the minimum pump work.

[0048] The heat dissipation device 100 provided by the present invention is different from the existing two-phase liquid cooling heat dissipation solutions. For example, heat pipes and heat plates all use capillary force as the driving force and have capillary limits. The pump-driven two-phase flow circuit of the present invention uses a mechanical pump as a forced driving force, and the circulation power is several orders of magnitude higher than the capillary force, and the corresponding heat dissipation capacity is also greatly improved; the pump-driven two-phase flow circuit uses a microchannel as a two-phase evaporator and a micropump as a power source, which has a small size and a low working fluid circulation flow rate, thereby overcoming the shortcomings of the split-type water-cooled heat dissipation device, which is large and inconvenient to carry, uses a single-phase water-cooled heat exchange method, has low heat exchange efficiency, and has high energy consumption for pumping and cooling fans; through the precise control of the two-phase heat exchange state of the evaporator and the optimized design of the high-efficiency microchannel evaporator structure, the heat exchange efficiency is greatly improved, the corresponding pumping and cooling energy consumption is small, and it is more energy-saving; through the temperature control of the liquid storage tank, the back pressure of the system can be adjusted, so that the system can dynamically adjust the heat dissipation level to adapt to different external environments, thereby avoiding the problem that the heat dissipation cold end of the existing heat dissipation device is greatly affected by the environment.

[0049] It can be understood that the heat dissipation device 100 is suitable for efficient heat dissipation of high-power distributed heat sources, especially in places with limited space. The use of a microchannel evaporator can meet the heat dissipation requirements of ultra-high heat flux density. According to the requirements of the use space, it can be used for heat dissipation of notebooks, servers or other high-heat electronic components. In addition, by replacing the form of the heat dissipation cold end, for example, changing the air-cooled heat dissipation to water-cooled heat dissipation can be applied to the integrated heat dissipation of large data centers; the air-cooled heat dissipation can also be transformed into a condensation radiation heat exchange form for efficient temperature control and heat dissipation of aerospace aircraft onboard equipment.

[0050] See also Figure 7 The present invention also provides an electronic device 200, comprising a heat source chip 201 and any one of the above-mentioned heat dissipation devices 100, wherein the microchannel evaporator 10 in the heat dissipation device 100 is fixed on the heat source chip 201, and a thermal interface layer 202 is arranged between the microchannel evaporator 10 and the heat source chip 201. Specifically, the material of the thermal interface layer 202 can be silicone grease, liquid metal, etc., for heat conduction. The electronic device 200 also includes a circuit board 203, on which the heat source chip 201 is arranged, and the microchannel evaporator 10 of the heat dissipation device 100 includes a fixing bar 103, which is fixed to the circuit board 203 by bolts. It should be noted that all embodiments of the heat dissipation device 100 provided by the present invention are applicable to the electronic device 200 provided by the present invention, and can achieve the same or similar beneficial effects.

[0051] In summary, the heat dissipation device 100 and the electronic device 200 provided by the present invention use the pump drive of the micro pump 30 as the circulation power of the two-phase liquid cooling heat dissipation circuit, the heat dissipation capacity is greatly improved, and the ability to resist external disturbance is strong; the microchannel evaporator 10 is small in size and high in relative area, which can meet the heat dissipation requirements of high heat flux density heat sources in a small space, and the channel inlet of the microchannel tube 141 is provided with a throttling groove 142, which can play the role of a throttling valve, can improve the boiling stability, and can also throttle and reduce the pressure by isenthalpy to spontaneously generate microbubbles, thereby enhancing the boiling heat exchange effect; the parallel connection of multiple evaporators can meet the heat dissipation requirements of distributed heat sources, and at the same time, the liquid storage tank 50 is used for temperature control and pressure regulation, and the heat regenerator 40 is used for heat recovery of the working fluid at the inlet and outlet of the evaporator, which can control the heat exchange state of the heat dissipation circuit, and optimize the heat exchange efficiency to the greatest extent while meeting the heat dissipation requirements, so as to achieve the minimum pump labor expenditure in exchange for the maximum heat dissipation benefit.

[0052] The above description is only an implementation mode of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A heat dissipation device, characterized in that: It includes a microchannel evaporator, a condenser, a micro pump, a regenerator and a pipeline; the outlet pipe of the microchannel evaporator is connected to the condenser through the pipeline, the condenser is connected to the micro pump through the pipeline, the micro pump is connected to the first end of the regenerator through the pipeline, the second end of the regenerator is connected to the outlet pipe of the microchannel evaporator through the pipeline, and the first end of the regenerator is also connected to the inlet pipe of the microchannel evaporator through the pipeline; The heat dissipation device further includes a liquid storage tank and a heating base, wherein the heating base carries the liquid storage tank, the heating base is connected to the condenser through the pipeline, and the liquid storage tank is connected to the micro pump through the pipeline; When the pipeline is full of liquid, the liquid storage tank contains liquid working fluid accounting for 30% to 60% of the total volume of the liquid storage tank; The condenser comprises a first heat dissipation rib, a first cooling fan paired with the first heat dissipation rib, a second heat dissipation rib, and a second cooling fan paired with the second heat dissipation rib; the heating base comprises a U-shaped pipe, a first open end of the U-shaped pipe is connected to the pipe between the first heat dissipation rib and the second heat dissipation rib through a flow regulating valve, and a second open end of the U-shaped pipe is connected to the pipe between the first heat dissipation rib and the second heat dissipation rib; When the ambient temperature rises and the cooling fan power reaches the maximum, but the subcooling degree of the working medium cannot reach the set value, or when the fluid entering the micro pump is in the two-phase region, the flow regulating valve connected to the liquid storage tank and the heating base is opened to allow the high-temperature working medium to flow into the heating base; The microchannel evaporator comprises an evaporator body, the evaporator body comprises a plurality of microchannel tubes arranged in parallel, one end of the microchannel tube close to the inlet tube is connected with a plurality of throttling grooves connected in series, two adjacent throttling grooves and a throttling groove and a microchannel tube are connected through a groove, and each throttling groove forms a U-shaped structure; The design parameters of the microchannel tube should satisfy the constraint number Co>0.5, and the Co number is defined as: Co= ; Among them, σ is the surface tension of the circulating working fluid, g is the acceleration of gravity, ρl is the density of the liquid working fluid, ρg is the density of the gaseous working fluid, and Di is the hydraulic diameter of the channel.

2. The heat dissipation device according to claim 1, characterized in that: The microchannel evaporator comprises a cover plate, which is arranged on the evaporator body. The inlet pipe is connected to one end of the evaporator body, and the outlet pipe is connected to the other end of the evaporator body.

3. The heat dissipation device according to claim 2, characterized in that: A buffer structure is provided between the microchannel tube and the inlet tube, and the buffer structure is also provided between the microchannel tube and the outlet tube.

4. The heat dissipation device according to claim 1, characterized in that: A first pressure transmitter and a temperature probe are arranged on the pipeline between the second heat dissipation fin and the micro pump.

5. The heat dissipation device according to claim 1, characterized in that: The number of the microchannel evaporators is multiple, and the multiple microchannel evaporators are connected in parallel.

6. An electronic device, characterized in that: It comprises a heat source chip and the heat dissipation device according to any one of claims 1 to 5, wherein a microchannel evaporator in the heat dissipation device is fixed on the heat source chip, and a thermal interface layer is arranged between the microchannel evaporator and the heat source chip.

7. The electronic device according to claim 6, characterized in that: It also includes a circuit board, the heat source chip is arranged on the circuit board, and the microchannel evaporator of the heat dissipation device includes a fixing bar, and the fixing bar is fixed to the circuit board by bolts.

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