Thermal management device

Abstract

The invention relates to a heat management device which comprises a plurality of heat pipe heat exchangers which are partially arranged in a nested mode, each heat pipe heat exchanger comprises an evaporation section and a condensation section, the arrangement height of the condensation section is larger than that of the evaporation section, and the condensation section of the inner-layer heat pipe heat exchanger is embedded in the evaporation section of the outer-layer heat pipe heat exchanger. The power element is arranged in the evaporation section of the heat pipe heat exchanger on the innermost layer and can directly make contact with the liquid working medium in the evaporation section of the outer layer, and the power element is arranged in the evaporation section of the heat pipe heat exchanger on the innermost layer and can directly make contact with the liquid working medium in the evaporation section of the innermost layer. And the gasification latent heat of the liquid working medium in the inner-layer heat pipe heat exchanger is greater than that of the liquid working medium in the outer-layer heat pipe heat exchanger. According to the heat management device provided by the invention, the problems that the heat transfer efficiency of a working medium is reduced and equipment is overheated or even damaged due to the fact that the working medium in an immersed phase change technology is easy to exceed critical heat flux density are solved.

Description

Technical Field

[0001] The present application relates to the field of heat pipe technology, and in particular to a heat management device. Background Art

[0002] As power components become smaller and smaller and their power density increases, common heat dissipation technologies can no longer meet the heat dissipation needs of power components.

[0003] Taking the immersion phase change technology as an example, it mainly uses the latent heat of vaporization of the working fluid to directly cool the power components, and its temperature uniformity and heat dissipation capacity are significantly improved compared with other heat dissipation methods. However, due to the existence of the nucleate boiling heat transfer inflection point, the heat dissipation capacity of the immersion phase change technology has decreased instead of increased.

[0004] It should be noted that the nucleate boiling heat transfer inflection point refers to the critical heat flux (CHF) in the boiling curve, which is the key turning point for the transition from nucleate boiling to film boiling. Specifically, after exceeding the critical heat flux, the bubble generation speed is too fast, and the bubbles merge to cover the heating surface to form a steam film (transforming into film boiling). At this time, due to the poor thermal conductivity of the steam film, which will hinder the contact between the liquid and the heating surface, the heat transfer coefficient of the working fluid drops sharply, the surface temperature of the power component rises sharply, and may even cause the equipment to burn out. Summary of the invention

[0005] Based on this, it is necessary to provide a thermal management device to solve the problem that the working fluid in the immersion phase change technology easily exceeds the critical heat flux density, thereby causing the heat transfer efficiency of the working fluid to decrease, and then causing equipment overheating or even damage.

[0006] The thermal management device provided in the present application includes a heat pipe heat exchanger with multiple parts nested, each heat pipe heat exchanger includes an evaporation section and a condensation section, the setting height of the condensation section is greater than the setting height of the evaporation section, the condensation section of the inner heat pipe heat exchanger is embedded in the evaporation section of the outer heat pipe heat exchanger, and can directly contact the liquid working medium in the outer evaporation section, the power element is arranged in the evaporation section of the innermost heat pipe heat exchanger, and can directly contact the liquid working medium in the innermost evaporation section; and the latent heat of vaporization of the liquid working medium in the inner heat pipe heat exchanger is greater than the latent heat of vaporization of the liquid working medium in the outer heat pipe heat exchanger.

[0007] In one embodiment, the number of heat pipe heat exchangers is two, which are defined as a first heat pipe and a second heat pipe respectively. The first heat pipe is provided with a first working fluid, and the second heat pipe is provided with a second working fluid. The latent heat of vaporization of the first working fluid is greater than the latent heat of vaporization of the second working fluid. The first heat pipe includes a first evaporation section and a first condensation section, and the second heat pipe includes a second evaporation section and a second condensation section. The power element is arranged in the first evaporation section and can directly contact the liquid first working fluid, and the first condensation section is inserted in the second evaporation section and can directly contact the liquid second working fluid.

[0008] In one embodiment, the power element is at least partially immersed in the liquid first working medium; And / or, the first condensation section is at least partially immersed in the liquid second working medium.

[0009] In one embodiment, the first heat pipe further comprises a first vortex pump, which is disposed in the first evaporation section so that the first working fluid in the first evaporation section can flow toward the surface of the power element; Alternatively, the first heat pipe further includes a first stirrer, which is disposed in the first evaporation section so that the first working medium in the first evaporation section can flow around the surface of the power element and form a vortex.

[0010] In one embodiment, the second heat pipe further comprises a second vortex pump, which is disposed in the second evaporation section so that the second working fluid in the second evaporation section can flow toward the surface of the first condensation section; Alternatively, the second heat pipe further includes a second agitator, which is disposed in the second evaporation section so that the second working medium in the second evaporation section can flow around the surface of the first condensation section and form a vortex.

[0011] In one embodiment, the first heat pipe further includes a first spray pipe group and a first liquid pump, the first spray pipe group is arranged on the outer peripheral side of the power element, the first liquid pump is immersed in the first working medium and connected to the first spray pipe group, so that the first working medium can be sprayed on the outer peripheral side of the power element through the first spray pipe group; And / or, the second heat pipe also includes a second spray pipe group and a second liquid pump, the second spray pipe group is arranged on the outer peripheral side of the first condensation section, the second liquid pump is immersed in the second working fluid and connected to the second spray pipe group, so that the second working fluid can be sprayed on the outer peripheral side of the first condensation section through the second spray pipe group.

[0012] In one embodiment, the first spray pipe group is mesh-shaped and is covered on the outer peripheral side of the power element. The first spray pipe group is provided with a plurality of first nozzles distributed at intervals. The first spray pipe group can spray the first working medium toward each heating surface of the power element through the plurality of first nozzles. And / or, the second spray pipe group is mesh-shaped and is covered on the outer peripheral side of the first condensation section. The second spray pipe group is provided with a plurality of second nozzles distributed at intervals. The second spray pipe group can spray the second working medium toward each heat exchange surface of the first condensation section through the plurality of second nozzles.

[0013] In one embodiment, the condensation section includes condensation flat tubes, inner condensation fins and outer condensation fins. There are multiple condensation flat tubes, each of which is connected to the evaporation section. The inner condensation fins are arranged in the corresponding condensation flat tubes. Adjacent condensation flat tubes are arranged at intervals to form condensation gaps, and the outer condensation fins are arranged in the corresponding condensation gaps.

[0014] In one embodiment, in the condensing section of the same heat pipe heat exchanger, the sum of the surface areas of all the inner condensing fins is greater than the sum of the surface areas of all the outer condensing fins, or the sum of the surface areas of all the inner condensing fins is less than the sum of the surface areas of all the outer condensing fins.

[0015] In one of the embodiments, the condensation section also includes an upper end plate, which is covered on the upper end surfaces of all the condensation flat tubes; the upper end surface of the external condensation fin and the upper end plate are spaced apart to form a first exhaust duct, so that the gas generated by the vaporization of the liquid working fluid around the external condensation fin can diffuse and escape to both ends of the length direction of the condensation gap through the first exhaust duct.

[0016] In one of the embodiments, the distance between the upper end surface of the outer condensing fin and the upper end plate is constant from one end of the condensing gap in the length direction to the other end of the condensing gap in the length direction.

[0017] Alternatively, along the distance from one end of the condensation gap length direction to the other end of the condensation gap length direction, the distance between the upper end surface of the external condensation fin and the upper end plate tends to increase or decrease, and the change trend of the distance between the upper end surface and the upper end plate of adjacent external condensation fins is opposite.

[0018] In one embodiment, the external condensation fins in each condensation gap are divided into a first fin and a second fin, the first fin and the upper end plate are spaced apart to form a first channel, the second fin and the upper end plate are spaced apart to form a second channel, the first channel and the second channel are connected to form a first exhaust channel, the first fin and the second fin are spaced apart along the length direction of the condensation gap to form a second exhaust channel, and the second exhaust channel is connected to the connecting point of the first channel and the second channel.

[0019] In one embodiment, along the distance from the end of the first branch channel close to the second branch channel to the end of the first branch channel away from the second branch channel, the distance between the upper end surface of the first fin and the upper end plate remains unchanged; Alternatively, the distance between the upper end surface of the first fin and the upper end plate tends to increase from one end of the first branch channel close to the second branch channel to one end of the first branch channel away from the second branch channel; and / or, along the distance from the end of the second branch channel close to the first branch channel to the end of the second branch channel away from the first branch channel, the distance between the upper end surface of the second fin and the upper end plate remains unchanged; Alternatively, the distance between the upper end surface of the second fin and the upper end plate tends to increase from an end of the second lane closer to the first lane to an end of the second lane farther from the first lane.

[0020] Compared with the prior art, the thermal management device provided by the present application has the condensing section of the inner heat pipe heat exchanger directly contacting the liquid working medium of the outer evaporation section, forming a step-by-step heat dissipation path. After the heat is transferred from the power element to the working medium of the innermost evaporation section, the working medium vaporizes and rises to the inner condensing section. The heat released by condensation is absorbed by the working medium of the outer evaporation section for the second time, forming a heat gradient transfer. This design reduces the single-stage heat flux density and avoids local overheating by dissipating heat in stages through multi-layer heat pipes.

[0021] Since the latent heat of vaporization of the inner working fluid is higher, it means that it produces less steam when absorbing the same amount of heat, thereby reducing the probability of bubbles merging to form a steam film, or delaying the occurrence of bubbles merging to form a steam film and covering the heating surface of the power element. Correspondingly, the latent heat of vaporization of the outer working fluid is lower, and it can be vaporized quickly to efficiently transfer the remaining heat. The synergistic effect of the two makes the heat evenly dispersed and avoids the occurrence of film boiling.

[0022] In summary, the sealed nested design (the condensing section of the inner heat pipe heat exchanger is embedded in the outer evaporating section) and the latent heat gradient configuration of the working fluid vaporization (the latent heat of vaporization of the inner working fluid is greater than that of the outer layer) can significantly improve the heat dissipation efficiency and avoid or delay the arrival of the critical heat flux density (CHF). BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 A schematic diagram of the structure of a thermal management device according to an embodiment of the present application; Figure 2 A cross-sectional view of a thermal management device according to an embodiment of the present application; Figure 3 A cross-sectional view of a thermal management device according to another embodiment of the present application; Figure 4 A schematic diagram of the structure of a condensation section of an embodiment provided in the present application; Figure 5A side view of a partial structure of a condensation section of an embodiment provided in the present application; Figure 6 A side view of a partial structure of a condensation section of another embodiment provided by the present application; Figure 7 A schematic diagram of a partial structure of a condensation section of another embodiment provided in the present application; Figure 8 A side view of the partial structure of a condensation section of yet another embodiment provided in the present application.

[0025] Figure numerals: 100, first heat pipe; 110, first evaporation section; 120, first condensation section; 130, first spray pipe group; 131, first nozzle; 140, first liquid pump; 200, second heat pipe; 210, second evaporation section; 220, second condensation section; 230, second spray pipe group; 231, second nozzle; 240, second liquid pump; 300, condensation flat tube; 310, condensation gap; 400, inner condensation fin; 500, outer condensation fin; 510, first fin; 520, second fin; 530, second exhaust duct; 600, upper end plate; 610, first exhaust duct; 611, first branch channel; 612, second branch channel; 620, plate body; 630, strip; 700, power element. DETAILED DESCRIPTION

[0026] As power components become smaller and smaller and their power density increases, common heat dissipation technologies can no longer meet the heat dissipation needs of power components.

[0027] Taking the immersion phase change technology as an example, it mainly uses the latent heat of vaporization of the working fluid to directly cool the power components, and its temperature uniformity and heat dissipation capacity are significantly improved compared with other heat dissipation methods. However, due to the existence of the nucleate boiling heat transfer inflection point, the heat dissipation capacity of the immersion phase change technology has decreased instead of increased.

[0028] It should be noted that the nucleate boiling heat transfer inflection point refers to the critical heat flux (CHF) in the boiling curve, which is the key turning point for the transition from nucleate boiling to film boiling. Specifically, after exceeding the critical heat flux, the bubble generation speed is too fast, and the bubbles merge to cover the heating surface to form a steam film (transforming into film boiling). At this time, due to the poor thermal conductivity of the steam film, which will hinder the contact between the liquid and the heating surface, the heat transfer coefficient of the working fluid drops sharply, the surface temperature of the power component rises sharply, and may even cause the equipment to burn out.

[0029] Therefore, in order to solve the problem that the working fluid in the immersion phase change technology easily exceeds the critical heat flux density, thereby causing the heat transfer efficiency of the working fluid to decrease, and then causing overheating or even damage to the equipment, the present application provides a thermal management device.

[0030] See also Figure 1-Figure 8 The thermal management device includes a plurality of partially nested heat pipe exchangers, each of which includes an evaporation section and a condensation section, and the condensation section is arranged at a height greater than the evaporation section.

[0031] The design of the condensation section being higher than the evaporation section can utilize gravity to drive the reflux of liquid working fluid, ensuring continuous liquid supply to the evaporation section and maintaining nucleate boiling stability.

[0032] The condensing section of the inner heat pipe heat exchanger is embedded in the evaporating section of the outer heat pipe heat exchanger and can directly contact the liquid working medium in the outer evaporating section. The power element 700 is arranged in the evaporating section of the innermost heat pipe heat exchanger and can directly contact the liquid working medium in the innermost evaporating section.

[0033] In this way, the condensing section of the inner heat pipe heat exchanger directly contacts the liquid working medium of the outer evaporation section, forming a step-by-step heat dissipation path. After the heat is transferred from the power element 700 to the working medium of the innermost evaporation section, the working medium vaporizes and rises to the inner condensing section. The heat released by condensation is absorbed by the working medium of the outer evaporation section for the second time, forming a heat gradient transfer. This design reduces the single-stage heat flux density and avoids local overheating through the staged heat dissipation of multi-layer heat pipes.

[0034] Furthermore, the latent heat of vaporization of the liquid working medium in the inner heat pipe heat exchanger is greater than the latent heat of vaporization of the liquid working medium in the outer heat pipe heat exchanger.

[0035] Since the latent heat of vaporization of the inner layer of working fluid is higher, it means that the amount of steam generated when it absorbs the same amount of heat is less, thereby reducing the probability of bubbles merging to form a steam film, or delaying the occurrence of bubbles merging to form a steam film and covering the heating surface of the power element 700. Correspondingly, the latent heat of vaporization of the outer layer of working fluid is lower, and it can be quickly vaporized to efficiently transfer the remaining heat. The synergistic effect of the two makes the heat evenly dispersed and avoids the occurrence of film boiling.

[0036] In summary, the sealed nested design (the condensing section of the inner heat pipe heat exchanger is embedded in the outer evaporating section) and the latent heat gradient configuration of the working fluid vaporization (the latent heat of vaporization of the inner working fluid is greater than that of the outer layer) can significantly improve the heat dissipation efficiency and avoid or delay the arrival of the critical heat flux density (CHF).

[0037] Specifically, the working fluid includes but is not limited to R134a (latent heat of vaporization is 217 kJ / kg, and its component is tetrafluoroethane), R471A (latent heat of vaporization is 230~250 kJ / kg, and it is mainly composed of R1234yf, R134a and R1234ze(E)), R1234yf (latent heat of vaporization is 145.37 kJ / kg, and its component is tetrafluoropropylene), R1233zd(E) (latent heat of vaporization is 185.3 kJ / kg, and its component is trans-1-chloro-3,3,3-trifluoropropylene), R1336mzz(Z) (latent heat of vaporization is 170 kJ / kg g, composed of hexafluoro-2-butene), R1234ze(E) (latent heat of vaporization value of 160 kJ / kg, composed of trans-1,3,3,3-tetrafluoropropene), R290 (latent heat of vaporization value of 427 kJ / kg, composed of propane), RE170 (latent heat of vaporization value of 481.5 kJ / kg, composed of ethylene), R601a (latent heat of vaporization value of 367 kJ / kg, composed of n-butane), R600 (latent heat of vaporization value of ~366.5 kJ / kg, composed of isobutane) and R600a (latent heat of vaporization value of 366.5 kJ / kg, mainly composed of isobutane) In one embodiment, if Figure 1-Figure 3 As shown, the number of heat pipe heat exchangers is two, which are defined as a first heat pipe 100 and a second heat pipe 200, respectively. A first working medium is arranged in the first heat pipe 100, and a second working medium is arranged in the second heat pipe 200. The latent heat of vaporization of the first working medium is greater than the latent heat of vaporization of the second working medium. The first heat pipe 100 includes a first evaporation section 110 and a first condensation section 120, and the second heat pipe 200 includes a second evaporation section 210 and a second condensation section 220. The power element 700 is arranged in the first evaporation section 110 and can directly contact the liquid first working medium, and the first condensation section 120 is inserted in the second evaporation section 210 and can directly contact the liquid second working medium.

[0038] In this configuration, the first working fluid (high latent heat of vaporization) directly cools the power element 700, absorbs a large amount of heat and then vaporizes, and the first condensation section 120 is inserted into the second evaporation section 210 to transfer the heat to the second working fluid (low latent heat of vaporization). The second working fluid vaporizes quickly and dissipates the heat to the external environment through its condensation section. This division of labor allows the high heat area (power element 700) to be processed by the high latent heat working fluid first, reducing the bubble generation rate, while the low latent heat working fluid is responsible for quickly exporting the remaining heat.

[0039] In addition, only two layers of nesting are used, which simplifies the complexity of the device while ensuring heat dissipation efficiency, making it suitable for scenarios with limited space.

[0040] However, it is not limited thereto. In other embodiments, a third heat pipe may be added outside the condensation section of the second heat pipe 200. The third heat pipe uses a third working medium whose latent heat of vaporization is less than that of the second working medium. The evaporation section of the third heat pipe is sleeved on the condensation section of the second heat pipe 200 to form a three-level heat dissipation chain, further dispersing the heat flux density.

[0041] Further, in one embodiment, if Figure 2 As shown, the power element 700 is at least partially immersed in the liquid first working medium, that is, the power element 700 is partially immersed in the liquid first working medium, or the power element 700 is completely immersed in the liquid first working medium.

[0042] Such an arrangement increases the contact area between the power element 700 and the first working medium, thereby preventing the power element 700 from being partially dry-burned.

[0043] Furthermore, in one embodiment, the first heat pipe 100 also includes a first vortex pump (not shown), which is disposed in the first evaporation section 110 so that the first working fluid in the first evaporation section 110 can flow toward the surface of the power element 700 .

[0044] The first vortex pump drives the first working fluid to impact the surface of the power element 700, destroying the boundary layer, strengthening convective heat transfer, and preventing bubbles from gathering on the heating surface. That is, such an arrangement can fundamentally solve the generation of steam film and avoid a sudden drop in heat transfer efficiency.

[0045] In another embodiment, the first heat pipe 100 further includes a first agitator (not shown), which is disposed in the first evaporation section 110 so that the first working fluid in the first evaporation section 110 can flow around the surface of the power element 700 and form a vortex.

[0046] The first agitator causes the first working medium to form a vortex around the power element 700, thereby extending the residence time of the first working medium and improving the phase change efficiency.

[0047] In summary, both the first vortex pump and the first agitator actively drive the flow of the first working fluid to control and delay the occurrence of CHF.

[0048] Furthermore, in other embodiments, impact flow and vortex flow may be respectively arranged in different areas on the outer peripheral side of the power element 700. For example, the first vortex pump is responsible for generating impact flow in the central high temperature area of ​​the surface of the power element 700, and the first agitator is responsible for generating vortex flow in the edge area of ​​the first evaporation section 110, thereby realizing zoned enhanced heat exchange.

[0049] Further, in one embodiment, if Figure 2 As shown, the first condensation section 120 is at least partially immersed in the liquid second working medium.

[0050] With such a configuration, by immersing the first condensing section 120 in the second working medium, the heat transfer efficiency of the first heat pipe 100 and the second heat pipe 200 can be improved through direct gas-to-liquid heat exchange.

[0051] Furthermore, in one embodiment, the second heat pipe 200 also includes a second vortex pump (not shown), which is disposed in the second evaporation section 210 so that the second working fluid in the second evaporation section 210 can flow toward the surface of the first condensation section 120 .

[0052] In this way, the second working medium is driven to impact the surface of the first condensation section 120, thereby accelerating the transfer of heat from the first condensation section 120 to the second working medium, thereby preventing the first condensation section 120 from being overheated again due to heat accumulation.

[0053] In another embodiment, the second heat pipe 200 further includes a second agitator (not shown), which is disposed in the second evaporation section 210 so that the second working fluid in the second evaporation section 210 can flow around the surface of the first condensation section 120 and form a vortex.

[0054] With such arrangement, a vortex is formed in the second evaporation section 210 surrounding the first condensation section 120, thereby increasing the contact time between the second working medium and the first condensation section 120 and improving the heat absorption efficiency of the second working medium.

[0055] In summary, it can be seen that both the second vortex pump and the second agitator actively drive the flow of the second working medium.

[0056] Furthermore, in other embodiments, the impact flow and the vortex flow may be respectively arranged in different areas on the outer peripheral side of the first condensation section 120. For example, the second vortex pump is responsible for generating the impact flow in the central high temperature area of ​​the surface layer of the first condensation section 120, and the second agitator is responsible for generating the vortex flow in the edge area of ​​the second evaporation section 210, thereby realizing zoned enhanced heat exchange.

[0057] In one embodiment, if Figure 3 As shown, the first heat pipe 100 also includes a first spray pipe group 130 and a first liquid pump 140. The first spray pipe group 130 is arranged on the outer peripheral side of the power element 700. The first liquid pump 140 is immersed in the first working fluid and connected to the first spray pipe group 130, so that the first working fluid can be sprayed on the outer peripheral side of the power element 700 through the first spray pipe group 130.

[0058] With such arrangement, the coverage of the first working fluid on the surface of the power element 700 is enhanced through active spraying, and since the sprayed first working fluid is continuously flowing, the bubbles attached to the surface of the power element 700 will be washed away in time, that is, a continuous steam film cannot be generated on the surface of the power element 700, thereby avoiding a sudden drop in heat transfer efficiency.

[0059] Further, in one embodiment, if Figure 3 As shown, the first spray pipe group 130 is mesh-shaped and covers the outer peripheral side of the power element 700. The first spray pipe group 130 is provided with a plurality of first nozzles 131 distributed at intervals. The first spray pipe group 130 can spray the first working medium toward each heating surface of the power element 700 through the plurality of first nozzles 131.

[0060] With this arrangement, on the one hand, the meshed first spray pipe group 130 covers the entire circumference of the power element 700, eliminating spray dead angles. On the other hand, the dense design of the first nozzles 131 achieves full coverage of the heat-generating surface of the power element 700, avoiding local heat flow concentration.

[0061] In one embodiment, if Figure 3 As shown, the second heat pipe 200 also includes a second spray pipe group 230 and a second liquid pump 240. The second spray pipe group 230 is arranged on the outer peripheral side of the first condensation section 120. The second liquid pump 240 is immersed in the second working fluid and connected to the second spray pipe group 230, so that the second working fluid can be sprayed on the outer peripheral side of the first condensation section 120 through the second spray pipe group 230.

[0062] With such a configuration, the coverage of the second working fluid on the surface of the first condensation section 120 is enhanced by active spraying, and since the sprayed second working fluid flows continuously, the bubbles attached to the surface of the first condensation section 120 will be washed away in time, that is, a continuous steam film cannot be generated on the surface of the first condensation section 120, thereby avoiding a sudden drop in heat transfer efficiency.

[0063] Further, in one embodiment, if Figure 3 As shown, the second spray pipe group 230 is mesh-shaped and is covered on the outer peripheral side of the first condensation section 120. The second spray pipe group 230 is provided with a plurality of spaced second nozzles 231. The second spray pipe group 230 can spray the second working fluid toward each heat exchange surface of the first condensation section 120 through the plurality of second nozzles 231.

[0064] With this arrangement, on the one hand, the meshed second spray pipe group 230 covers the entire circumference of the first condensation section 120, eliminating spray dead angles. On the other hand, through the dense design of the second nozzles 231, the entire heat exchange surface of the first condensation section 120 is covered to avoid local heat flow concentration.

[0065] In other embodiments, a micro-atomizer may be integrated in the first nozzle 131 or the second nozzle 231 to atomize the first working fluid or the second working fluid into micron-sized droplets for spraying, thereby increasing the gas-liquid contact area and improving the phase change efficiency.

[0066] In one embodiment, if Figure 2-Figure 4As shown, the condensation section includes condensation flat tubes 300, inner condensation fins 400 and outer condensation fins 500. There are multiple condensation flat tubes 300, each condensation flat tube 300 is connected to the evaporation section respectively, the inner condensation fins 400 are arranged in the corresponding condensation flat tubes 300, adjacent condensation flat tubes 300 are arranged at intervals to form a condensation gap 310, and the outer condensation fins 500 are arranged in the corresponding condensation gap 310.

[0067] In this way, multiple condensation flat tubes 300 are arranged in parallel, which can increase the heat dissipation area of ​​the condensation section, and the flat cross section of the condensation is conducive to the rapid diffusion of steam. The inner condensation fins 400 are arranged in the condensation flat tubes 300 to increase the heat exchange area inside the condensation flat tubes 300. Correspondingly, the outer condensation fins 500 are arranged in the condensation gap 310 to enhance external heat dissipation.

[0068] But not limited to this, in other embodiments, the condensation flat tube 300 can be replaced with a corrugated tube, and the turbulent effect of the corrugated structure can be used to enhance the heat exchange in the corrugated tube. At the same time, the outer condensation fin 500 or the inner condensation fin 400 can use porous materials to increase the surface area.

[0069] Further, in one embodiment, in the condensing section of the same heat pipe heat exchanger, the sum of the surface areas of all the inner condensing fins 400 is greater than the sum of the surface areas of all the outer condensing fins 500 .

[0070] It can be understood that the heat exchange in the condensation flat tube 300 is the liquefaction heat release of the gaseous first working fluid, and the heat exchange in the condensation gap 310 is the absorption of the liquid second working fluid. Obviously, the heat exchange efficiency of the liquid second working fluid is greater than the heat exchange efficiency of the gaseous first working fluid. Therefore, by setting the sum of the surface areas of all the inner condensation fins 400 to be greater than the sum of the surface areas of all the outer condensation fins 500, it can be effectively ensured that the heat exchange efficiency inside and outside the condensation flat tube 300 remains balanced.

[0071] In another embodiment, the sum of the surface areas of all the inner condensing fins 400 is less than the sum of the surface areas of all the outer condensing fins 500 .

[0072] At this time, the second condensation section 220 of the second heat pipe exchanges heat with the air, and the specific heat capacity of the air is often smaller than the specific heat capacity of the second working fluid. Therefore, the sum of the surface areas of all the external condensation fins 500 is larger, which is conducive to balancing the heat exchange balance inside and outside the second condensation section 220.

[0073] Furthermore, in one embodiment, in the condensing section of the same heat pipe heat exchanger, the sum of the surface areas A of all the inner condensing fins 400 and the sum of the surface areas B of all the outer condensing fins 500 satisfy: 1

[0074] ​Such an arrangement can achieve a dynamic balance between the heat release of liquefaction of the gaseous first working medium and the heat absorption of the liquid second working medium.

[0075] In one embodiment, the surface roughness Q of the inner condensing fin 400 satisfies 0.1 μm≤Q≤3 μm.

[0076] With this configuration, a moderately rough surface can promote droplet nucleation and aggregation and dripping, thereby accelerating the condensation process. However, too high a roughness will increase the flow resistance of the first working fluid or the second working fluid. Therefore, this range balances the nucleation efficiency and the flow resistance.

[0077] In one embodiment, the surface roughness P of the outer condensing fin 500 satisfies 0.1 μm≤P≤3 μm.

[0078] With this configuration, a moderately rough surface can promote droplet nucleation and aggregation and dripping, thereby accelerating the condensation process. However, too high a roughness will increase the flow resistance of the first working fluid or the second working fluid. Therefore, this range balances the nucleation efficiency and the flow resistance.

[0079] In one embodiment, if Figure 2-Figure 8 As shown, the condensation section further includes an upper end plate 600 , which is disposed on the upper end surfaces of all the condensation flat tubes 300 .

[0080] It should be noted that a balance cavity is provided between the upper end plate 600 and the condensation flat tube 300 so that the gaseous working medium can be evenly distributed through the balance cavity. Figure 5-Figure 8 As shown, the upper end surface of the external condensation fin 500 and the upper end plate 600 are spaced apart to form a first exhaust channel 610, so that the gas generated by the vaporization of the liquid working medium around the external condensation fin 500 can diffuse and escape to both ends of the length direction of the condensation gap 310 through the first exhaust channel 610.

[0081] It should be noted that the height direction of the condensation gap 310 is the direction from the evaporation section to the condensation section, the width direction of the condensation gap 310 is the direction in which the multiple condensation flat tubes 300 are arranged, and the length direction of the condensation gap 310 is the horizontal extension direction of the condensation flat tubes 300.

[0082] Such an arrangement allows the vaporized working medium to escape along both ends of the condensation gap 310 , thereby preventing the gas from being retained in the condensation gap 310 and affecting the heat exchange of the working medium.

[0083] Specifically, in one embodiment, if Figure 5-Figure 8As shown, the upper end plate 600 includes a plate body 620 and a strip 630. The plate body 620 is arranged on the upper end surfaces of all the condensation flat tubes 300 to seal the condensation flat tubes 300. The strips 630 and the condensation gaps 310 are arranged in a one-to-one correspondence, and one end of each strip 630 is connected to the plate body 620, and the other end extends to the condensation gap 310 and is spaced apart from the external condensation fins 500 to form a first exhaust duct 610.

[0084] A customized first exhaust passage 610 is formed by spacing the slats 630 and the outer condensation fins 500 to ensure uniform diffusion of the gas and avoid local blockage.

[0085] It should be noted that the lower end surface of the external condensing fin 500 and the bottom seal are also arranged at intervals to facilitate rapid reflux of the working fluid after condensation.

[0086] Further, in one embodiment, if Figure 5 As shown, along the distance from one end of the condensation gap 310 in the length direction to the other end of the condensation gap 310 in the length direction, the distance between the upper end surface of the outer condensation fin 500 and the upper end plate 600 remains unchanged.

[0087] It should be noted that the first exhaust duct 610 extends obliquely upward, and the directions of adjacent first exhaust ducts 610 are opposite, one extending toward the upper right and the other extending toward the upper left. In addition, the channel direction of the outer condensing fin 500 is consistent with the direction of the first exhaust duct 610.

[0088] This setting is suitable for evenly heated scenes and is conducive to the uniform discharge of gas.

[0089] In another embodiment, if Figure 6 As shown, along the distance from one end of the condensation gap 310 in the length direction to the other end of the condensation gap 310 in the length direction, the distance between the upper end surface of the outer condensation fin 500 and the upper end plate 600 tends to increase or decrease.

[0090] Such a setting can guide the gas to be discharged to the low-pressure area, relieve the gas accumulation pressure, and reduce the gas flow resistance.

[0091] Furthermore, the variation trends of the spacings between the upper end surfaces of adjacent outer condensing fins 500 and the upper end plate 600 are opposite.

[0092] Such an arrangement makes the amount distribution of the gaseous working medium escaping from both sides of the condensation section more uniform.

[0093] However, the present invention is not limited thereto. In other embodiments, a plurality of diameter-changing sections may be provided along the length direction of the condensation gap 310 to form a Venturi effect and accelerate the discharge of gas.

[0094] In one embodiment, if Figure 7-Figure 8As shown, the external condensation fin 500 in each condensation gap 310 is divided into a first fin 510 and a second fin 520. The first fin 510 and the upper end plate 600 are spaced apart to form a first channel 611. The second fin 520 and the upper end plate 600 are spaced apart to form a second channel 612. The first channel 611 and the second channel 612 are connected to form a first exhaust channel 610. The first fin 510 and the second fin 520 are spaced apart along the length direction of the condensation gap 310 to form a second exhaust channel 530. The second exhaust channel 530 is connected at the connecting point between the first channel 611 and the second channel 612.

[0095] In this way, the first branch channel 611 and the second branch channel 612 are connected, allowing the gas to be discharged in a split manner, reducing the turbulence in the first exhaust channel 610, and the second exhaust channel 530 further disperses the airflow to avoid backflow interference.

[0096] Furthermore, in one embodiment, a guide fin may be provided between the first branch channel 611 and the second branch channel 612 to force the airflow to turn and enhance the contact between the gas and the external condensation fin 500 .

[0097] Further, in one embodiment, if Figure 7 As shown, along the distance from one end of the first lane 611 close to the second lane 612 to one end of the first lane 611 away from the second lane 612, the distance between the upper end surface of the first fin 510 and the upper end plate 600 remains unchanged.

[0098] Specifically, the first branch channel 611 and the second branch channel 612 extend in opposite obliquely upward directions, so that bubbles can escape upward and outward from the first exhaust channel 610 under the action of gravity. In addition, the extension direction of the internal channel of the first fin 510 is consistent with the extension direction of the first branch channel 611, and the extension direction of the internal channel of the second fin 520 is consistent with the extension direction of the second branch channel 612.

[0099] This setting is suitable for evenly heated scenes and is conducive to the uniform discharge of gas.

[0100] In another embodiment, if Figure 8 As shown, along the direction from the end of the first lane 611 close to the second lane 612 to the end of the first lane 611 away from the second lane 612, the distance between the upper end surface of the first fin 510 and the upper end plate 600 tends to increase.

[0101] Such a setting can guide the gas to be discharged to the low-pressure area, relieve the gas accumulation pressure, and reduce the gas flow resistance.

[0102] In one embodiment, if Figure 7As shown, along the distance from the end of the second lane 612 close to the first lane 611 to the end of the second lane 612 away from the first lane 611, the distance between the upper end surface of the second fin 520 and the upper end plate 600 remains unchanged.

[0103] This setting is suitable for evenly heated scenes and is conducive to the uniform discharge of gas.

[0104] In another embodiment, if Figure 8 As shown, along the direction from the end of the second lane 612 close to the first lane 611 to the end of the second lane 612 away from the first lane 611, the distance between the upper end surface of the second fin 520 and the upper end plate 600 tends to increase.

[0105] Such a setting can guide the gas to be discharged to the low-pressure area, relieve the gas accumulation pressure, and reduce the gas flow resistance.

[0106] In one embodiment, the maximum liquid level of the liquid working medium in the evaporation section is lower than the lower end surface of the condensation section.

[0107] By controlling the liquid level, we can prevent the liquid level from being too high, ensure that the working fluid in the evaporation section only flows back through capillary force or gravity, avoid steam carrying droplets into the condensation section, and maintain the stability of the two-phase flow.

[0108] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0109] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of patent protection of the present application shall be subject to the attached claims.

[0110] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0111] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0112] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0113] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0114] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0115] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

Claims

1. A thermal management device, characterized in that: A heat pipe heat exchanger comprising a plurality of partially nested arrangements, each of the heat pipe heat exchangers comprising an evaporation section and a condensation section, the condensation section being arranged at a height greater than the evaporation section, the condensation section of the inner heat pipe heat exchanger being arranged in the evaporation section of the outer heat pipe heat exchanger and being able to directly contact the liquid working medium in the outer evaporation section, and the power element (700) being arranged in the evaporation section of the innermost heat pipe heat exchanger and being able to directly contact the liquid working medium in the innermost evaporation section; Furthermore, the latent heat of vaporization of the liquid working medium in the inner heat pipe heat exchanger is greater than the latent heat of vaporization of the liquid working medium in the outer heat pipe heat exchanger.

2. The thermal management device according to claim 1, characterized in that: The number of the heat pipe heat exchangers is two, which are defined as a first heat pipe (100) and a second heat pipe (200), the first heat pipe (100) being provided with a first working fluid, the second heat pipe (200) being provided with a second working fluid, and the latent heat of vaporization of the first working fluid being greater than the latent heat of vaporization of the second working fluid; The first heat pipe (100) comprises a first evaporation section (110) and a first condensation section (120); the second heat pipe (200) comprises a second evaporation section (210) and a second condensation section (220); the power element (700) is arranged in the first evaporation section (110) and is capable of directly contacting a liquid first working medium; and the first condensation section (120) is inserted in the second evaporation section (210) and is capable of directly contacting a liquid second working medium.

3. The thermal management device according to claim 2, characterized in that: The power element (700) is at least partially immersed in the liquid first working medium; And / or, the first condensation section (120) is at least partially immersed in the liquid second working medium.

4. The thermal management device according to claim 3, characterized in that: The first heat pipe (100) further comprises a first vortex pump, the first vortex pump being arranged in the first evaporation section (110) so as to enable the first working fluid in the first evaporation section (110) to flow toward the surface of the power element (700) in an impact manner; Alternatively, the first heat pipe (100) further comprises a first stirrer, the first stirrer being arranged in the first evaporation section (110) so as to enable the first working fluid in the first evaporation section (110) to flow around the surface of the power element (700) and form a vortex.

5. The thermal management device according to claim 3, characterized in that: The second heat pipe (200) further comprises a second vortex pump, the second vortex pump being arranged in the second evaporation section (210) so as to enable the second working fluid in the second evaporation section (210) to flow toward the surface of the first condensation section (120); Alternatively, the second heat pipe (200) further comprises a second stirrer, which is arranged in the second evaporation section (210) so that the second working fluid in the second evaporation section (210) can flow around the surface of the first condensation section (120) and form a vortex.

6. The thermal management device according to claim 2, characterized in that: The first heat pipe (100) further comprises a first spray pipe group (130) and a first liquid pump (140); the first spray pipe group (130) is arranged on the outer peripheral side of the power element (700); the first liquid pump (140) is immersed in the first working medium and is connected to the first spray pipe group (130), so that the first working medium can be sprayed on the outer peripheral side of the power element (700) through the first spray pipe group (130); And / or, the second heat pipe (200) further comprises a second spray pipe group (230) and a second liquid pump (240), wherein the second spray pipe group (230) is arranged on the outer peripheral side of the first condensation section (120), and the second liquid pump (240) is immersed in the second working fluid and connected to the second spray pipe group (230), so that the second working fluid can be sprayed on the outer peripheral side of the first condensation section (120) through the second spray pipe group (230).

7. The thermal management device according to claim 6, characterized in that: The first spray pipe group (130) is in a mesh shape and is arranged on the outer peripheral side of the power element (700). The first spray pipe group (130) is provided with a plurality of first nozzles (131) distributed at intervals. The first spray pipe group (130) can spray the first working medium toward each heating surface of the power element (700) through the plurality of first nozzles (131); And / or, the second spray pipe group (230) is mesh-shaped and is arranged on the outer peripheral side of the first condensation section (120), and the second spray pipe group (230) is provided with a plurality of second nozzles (231) distributed at intervals, and the second spray pipe group (230) can spray the second working fluid toward each heat exchange surface of the first condensation section (120) through the plurality of second nozzles (231).

8. The thermal management device according to claim 1, characterized in that: The condensation section includes a condensation flat tube (300), an inner condensation fin (400) and an outer condensation fin (500), the number of the condensation flat tube (300) is multiple, each of the condensation flat tubes (300) is connected to the evaporation section, the inner condensation fin (400) is arranged in the corresponding condensation flat tube (300), the adjacent condensation flat tubes (300) are arranged at intervals to form a condensation gap (310), and the outer condensation fin (500) is arranged in the corresponding condensation gap (310).

9. The thermal management device according to claim 8, characterized in that: In the condensing section of the same heat pipe heat exchanger, the sum of the surface areas of all the inner condensing fins (400) is greater than the sum of the surface areas of all the outer condensing fins (500), or the sum of the surface areas of all the inner condensing fins (400) is less than the sum of the surface areas of all the outer condensing fins (500).

10. The thermal management device according to claim 8, characterized in that: The condensation section further comprises an upper end plate (600), wherein the upper end plate (600) is arranged to cover the upper end surfaces of all the condensation flat tubes (300); The upper end surface of the external condensation fin (500) and the upper end plate (600) are spaced apart to form a first exhaust channel (610), so that the gas generated by the vaporization of the liquid working medium around the external condensation fin (500) can diffuse and escape to both ends of the condensation gap (310) in the length direction through the first exhaust channel (610).

11. The thermal management device according to claim 10, characterized in that: Along the distance from one end of the condensation gap (310) in the length direction to the other end of the condensation gap (310) in the length direction, the distance between the upper end surface of the external condensation fin (500) and the upper end plate (600) remains unchanged; Alternatively, along the distance from one end of the condensation gap (310) in the length direction to the other end of the condensation gap (310) in the length direction, the distance between the upper end surface of the external condensation fin (500) and the upper end plate (600) tends to increase or decrease, and the distance between the upper end surface of adjacent external condensation fins (500) and the upper end plate (600) has an opposite trend of change.

12. The thermal management device according to claim 10, characterized in that: The external condensation fin (500) in each of the condensation gaps (310) is divided into a first fin (510) and a second fin (520); the first fin (510) and the upper end plate (600) are spaced apart to form a first branch channel (611); the second fin (520) and the upper end plate (600) are spaced apart to form a second branch channel (612); the first branch channel (611) and the second branch channel (612) are connected to form the first exhaust channel (610); the first fin (510) and the second fin (520) are spaced apart along the length direction of the condensation gap (310) to form a second exhaust channel (530); the second exhaust channel (530) is connected to the connecting point between the first branch channel (611) and the second branch channel (612).

13. The thermal management device according to claim 12, characterized in that: Along the distance from one end of the first branch channel (611) close to the second branch channel (612) to one end of the first branch channel (611) far from the second branch channel (612), the distance between the upper end surface of the first fin (510) and the upper end plate (600) remains unchanged; Alternatively, along the direction from one end of the first branch channel (611) close to the second branch channel (612) to one end of the first branch channel (611) far from the second branch channel (612), the distance between the upper end surface of the first fin (510) and the upper end plate (600) tends to increase; and / or, along the distance from one end of the second branch channel (612) close to the first branch channel (611) to one end of the second branch channel (612) far from the first branch channel (611), the distance between the upper end surface of the second fin (520) and the upper end plate (600) remains unchanged; Alternatively, the distance between the upper end surface of the second fin (520) and the upper end plate (600) tends to increase from one end of the second branch channel (612) closer to the first branch channel (611) to one end of the second branch channel (612) farther from the first branch channel (611).

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