Loop heat pipe based on multi-mode high-efficiency condensation

Abstract

The present invention discloses a loop heat pipe based on multi-mode efficient condensation. The loop heat pipe includes multiple gas pipelines, multiple liquid pipelines, multiple evaporators and condensers; multiple evaporators are connected in parallel with the steam chamber of the condenser through multiple gas pipelines, and multiple evaporators are also connected in parallel with the condensation liquid chamber of the condenser through multiple liquid pipelines. The loop heat pipe with multiple evaporators and a single condenser of the present invention realizes a loop heat pipe in which one condenser drives multiple evaporators through a novel condenser and evaporator structure with an ingenious design concept and a reasonable structure. While ensuring heat dissipation efficiency, it meets the requirements of miniaturization, can be flexibly installed according to the number and position of heating elements, and can select different heat dissipation modes according to the requirements of different heat dissipation loads to avoid energy waste.

Description

Technical Field

[0001] The present invention belongs to the field of thermal control technology, and in particular relates to a loop heat pipe based on multi-mode high-efficiency condensation. Background Art

[0002] Nowadays, the high heat dissipation issues caused by the miniaturization and high integration of electronic devices and equipment have become a key factor restricting and affecting the further development of aerospace, new energy development, integrated circuits and other fields. Therefore, heat pipes, as one of the most effective heat exchange devices, play an increasingly important role. They are two-phase heat transfer components with high heat transfer capabilities. They consist of an evaporation section, a condensation section, and an adiabatic section. The working fluid absorbs heat in the evaporation section, turning into vapor, and then releases heat in the condensation section. The condensate flows back to the evaporation section through the capillary wick. Traditional heat pipes are widely used due to their high thermal conductivity and passive cooling advantages, but they have problems such as coolant leakage and inability to meet long-distance transportation requirements.

[0003] The emergence of loop heat pipes (Loop Heat Pipe, LHP) can better solve the problems of leakage and inability to transport heat over long distances in traditional heat pipes. It consists of an evaporator, a condenser, a liquid pipe, a gas pipe and a compensator. It relies on the capillary force of the liquid wick in the evaporator to circulate the working fluid in the loop. Since the loop heat pipe only has a liquid wick in the evaporator, and the liquid and gas pipelines are separated, the flow resistance of the working fluid is small, long-distance heat transfer can be achieved, and leakage problems are not prone to occur. However, in the face of the problem of multi-heat source cooling or large-area heat source heat dissipation, the one-to-single, point-to-point heat dissipation mode of the loop heat pipe is no longer applicable. Therefore, a multi-evaporator loop heat pipe for matching multi-point heat sources with a single-point cold source heat transmission came into being.

[0004] The loop heat pipe with multiple evaporators and a single condenser has obvious advantages over the traditional loop heat pipe. For example, it can match the heat dissipation of multiple heat sources or large-area heat sources, and has a higher heat transfer limit and can withstand higher heat flux density. However, the loop heat pipe with multiple evaporators still has defects. First, the heat load brought by multiple evaporators poses a challenge to the heat dissipation capacity of the condenser. The sum of the heat loads carried by each evaporator will cause the load on the condenser to be extremely high. Secondly, when an evaporator is not working, the heat load reaching the condensing end is reduced. The same heat dissipation mode is bound to cause energy waste. How to control the heat dissipation mode of the condensing end to match the optimal heat load? Moreover, whether the non-working evaporator can be utilized to achieve the most efficient heat dissipation, thereby improving the working efficiency of the entire loop heat pipe, these are all technical problems that need to be solved. Summary of the Invention

[0005] The object of the present invention is to provide a loop heat pipe based on multi-mode high-efficiency condensation in order to solve the above problems.

[0006] In order to achieve its purpose, the present invention adopts the following technical solutions:

[0007] A polygonal star-shaped fin microchannel condenser, wherein the main body of the condenser is in the shape of a rectangular parallelepiped, and the interior of the main body is provided with a first baffle, a second baffle, a third baffle, and a fourth baffle from top to bottom, which divide the inner cavity of the main body into an upper cooling fluid cavity, a steam cavity, a heat exchange cavity, a condensate cavity, and a lower cooling fluid cavity in sequence from top to bottom; the upper cooling fluid cavity is provided with a first cooling fluid outlet, the lower cooling fluid cavity is provided with a first cooling fluid inlet, the heat exchange cavity is provided with a second cooling fluid inlet and a second cooling fluid outlet, the steam cavity is provided with a steam inlet, and the condensate cavity is provided with a condensate outlet;

[0008] A plurality of hollow cylindrical fins arranged in a determinant pattern are provided in the heat exchange cavity. The hollow cylindrical fins include a sleeved outer tube and an inner tube. The interior of the inner tube serves as a cooling fluid microchannel for the circulation of the cooling fluid, and the space between the outer tube and the inner tube serves as a steam channel for the circulation of steam. The cross section of the outer tube is a polygonal star. A plurality of channel partitions are provided between the outer tube and the inner tube to divide the steam channel into a plurality of vertically penetrating microchannels. One end of the channel partition is connected to the outer tube and the other end is connected to the inner tube, so that each convex corner of the polygonal star-shaped outer tube and the space between the inner tube constitute a corresponding microchannel. The hollow cylindrical fins in adjacent columns and rows are staggered.

[0009] The top end of the outer tube of the hollow cylindrical fin is connected to the second partition plate, and the bottom end is connected to the third partition plate. Through holes are provided at the locations where the second partition plate and the third partition plate are connected to the outer tube, so that the outer tube is connected to the steam chamber and the condensate chamber respectively.

[0010] The top end of the inner tube of the hollow cylindrical fin extends upward beyond the outer tube to connect with the first baffle, and the bottom end extends downward beyond the bottom end of the outer tube to connect with the fourth baffle. Through holes are provided at the locations where the first baffle and the fourth baffle connect with the inner tube, so that the inner tube communicates with the upper cooling fluid cavity and the lower cooling fluid cavity respectively.

[0011] Several ventilation windows are provided on the two opposite side walls of the heat exchange chamber. An electric fan is also provided on one of the side walls for blowing cool air into the heat exchange chamber to dissipate heat. Baffles are provided around the side wall where the electric fan is provided to surround the electric fan in the middle.

[0012] Preferably, a fan bracket is provided on the side wall of the heat exchange chamber where the electric fan is provided, for installing the electric fan, and the electric fan is electrically connected to an external power supply, so that the electric fan and the heat exchange chamber are integrated and easy to install.

[0013] The present invention provides a loop heat pipe based on multi-mode high-efficiency condensation, comprising multiple gas pipelines, multiple liquid pipelines, multiple evaporators and a condenser as described in any of the above items; the multiple evaporators are connected in parallel with the steam chamber of the condenser through the multiple gas pipelines, and the multiple evaporators are also connected in parallel with the condensation liquid chamber of the condenser through the multiple liquid pipelines.

[0014] Preferably, the loop heat pipe also includes a liquid reservoir, which is connected to the multiple liquid pipelines respectively through multiple liquid replenishment lines. The liquid replenishment lines transport the liquid in the liquid reservoir to the liquid pipeline and then into the evaporator for liquid compensation, ensuring that there is sufficient heat exchange liquid in the evaporator to prevent dry burning.

[0015] The evaporator of the above-mentioned loop heat pipe based on multi-mode high-efficiency condensation is evaporator A or evaporator B.

[0016] The evaporator A comprises an evaporator shell A and a liquid wick A. The liquid wick A is arranged in the middle of the evaporator shell A, dividing the two ends of the inner cavity of the evaporator A into an evaporator gas cavity A and an evaporator liquid cavity A;

[0017] The main body of the liquid absorbent core A is a rectangular parallelepiped, with the bottom surface of the main body being the heated surface A, the left side being the air outlet end A, and the right side being the liquid absorption end A; the right side of the liquid absorbent core A is recessed inward to form a liquid storage tank A; a plurality of steam channels parallel to the heated surface A are provided on the outer surfaces of the front and rear sides of the liquid absorbent core A, one end of the steam channel reaches the air outlet end A and communicates with the evaporator gas chamber A, while the other end is spaced apart from the liquid absorption end A; the heated surface A of the liquid absorbent core A extends toward the evaporator gas chamber A to form an extended surface, which is used to cover the surface of the evaporator gas chamber A in contact with the heating element;

[0018] A top gas channel and a plurality of intermediate gas channels are provided inside the absorbent core A. The top gas channel and the intermediate gas channel extend from the gas outlet end A to the liquid absorption end A, and a distance is left between the liquid absorption end A; the intermediate gas channel runs vertically from the top surface to the bottom surface of the absorbent core A and is arranged parallel to the front and rear side surfaces of the absorbent core A; the top gas channel runs between the front and rear side surfaces of the absorbent core A and is connected to the intermediate gas channel;

[0019] The intermediate gas channel divides the part of the liquid wick A near the air outlet end A into several liquid wick chips parallel to the front and rear sides of the liquid wick A. The liquid wick chip is provided with several liquid channels A parallel to the heating surface A from top to bottom. One end of the liquid channel A extends to the liquid storage tank A and is connected to the evaporator liquid cavity A, while the other end is spaced apart from the air outlet end A.

[0020] Preferably, the top of the absorbent core in the absorbent core A is in the shape of an arc surface, which further increases the evaporation area of ​​the absorbent core, allows the heat exchange cycle to proceed faster, and further improves the heat exchange efficiency.

[0021] The evaporator B includes an evaporator shell B and a liquid wick B. The liquid wick B includes a liquid barrier plate at the top and a heat receiving block at the bottom. A plurality of hollow cylindrical liquid channels B arranged in an array are provided between the liquid barrier plate and the heat receiving block. One end of the liquid channel B is connected to the liquid barrier plate, and the other end is connected to the heat receiving block.

[0022] The liquid wick B is disposed within the evaporator housing B. The size of the liquid partition plate matches that of the evaporator housing B, separating the top of the evaporator housing B into an evaporator liquid chamber B capable of storing condensed liquid. A through hole is provided on the liquid partition plate where it connects to the liquid channel B, thereby allowing the evaporator liquid chamber B to communicate with the liquid channel B.

[0023] The heat receiving block contacts the bottom surface of the evaporator shell B to receive the heat conducted by the heating element; the middle cavity in the evaporator shell B serves as the evaporator gas cavity B, and the cavity of the evaporator gas cavity B is provided with a steam outlet for connecting to the gas pipeline, and the cavity of the evaporator liquid cavity B is provided with a condensate inlet for connecting to the liquid pipeline.

[0024] Preferably, on the liquid absorbent core B, the liquid partition plate is surrounded by a surrounding plate to enclose the top of the liquid absorbent core B into a liquid storage tank B for storing heat exchange medium to ensure that the evaporator has sufficient heat exchange medium to prevent dry burning.

[0025] Preferably, in the evaporator B, a distance is left between the side wall of the evaporator shell B where the steam outlet is provided and the liquid channel B to accelerate the flow of steam.

[0026] Preferably, in any of the above-mentioned loop heat pipes based on multi-mode high-efficiency condensation, the number of the evaporators is 4, and the outer tube of the hollow cylindrical fin is in the shape of a hexagonal star.

[0027] The beneficial effects of the present invention are:

[0028] 1. The condenser of the present invention adopts hollow cylindrical fins with microchannels arranged in an array. The steam directly undergoes phase change and condenses into liquid on the wall of the microchannel. The cylindrical fins can reduce the flow resistance of the cooling fluid. The fins are innovatively divided into a sheathed outer tube and an inner tube, and the outer tube is designed to be a polygonal star. The inner tube is sheathed in the middle of the outer tube, and the cooling fluid flows in the inner tube. Compared with only introducing the cooling fluid into the heat exchange cavity, only the outside of the fin exchanges heat with the cooling fluid. The structure of the inner tube sheathed in the outer tube of the present invention allows both the inside and the outside of the outer tube to contact the cooling fluid, which greatly improves Heat exchange efficiency and working efficiency of the condenser; the outer tube is designed to be a polygonal star, and a channel partition is arranged inside the outer tube so that the side wall of the outer tube is surrounded by a micro channel with multiple angles, and the existence of the angle can accelerate the liquefaction of steam. The steam contacts the side wall of the micro channel and condenses into liquid. The micro droplets gather on the side wall to form a stream and flow downward, which accelerates the overall liquefaction and convergence flow process of the steam in the micro channel, improves the temperature uniformity in the micro channel, and improves the heat exchange efficiency; the working efficiency of the condenser of the present invention is significantly improved, laying the foundation for one condenser to drive multiple evaporators to work.

[0029] 2. The condenser of the present invention is provided with an integrated structure integrating natural cooling, air cooling and liquid cooling. One condenser can provide three heat dissipation modes, namely natural convection, air cooling and liquid cooling. When using air cooling or natural convection cooling, the ventilation window is opened, and when using liquid cooling with cooling fluid flowing in the heat exchange chamber, the ventilation window is closed. Different heat dissipation modes can be selected according to the heat load of the evaporator and the number of working evaporators. When the heat dissipation load is very high or relatively high, the first and second cooling fluid inlets are opened at the same time, so that the cooling fluid flows in both the inner tube and the heat exchange chamber, or a heat dissipation method of using electric fan air cooling + cooling fluid flowing in the inner tube can be selected. When the heat dissipation load is low, it is possible to choose to use cooling fluid flowing in the heat exchange chamber alone, or air cooling, or natural convection cooling. The integrated design of multiple heat dissipation modes of the condenser can meet the different working modes of the loop heat pipe of multiple evaporators, and the heat dissipation mode can be flexibly selected according to the number of evaporators that need to be worked. When an evaporator is not working, the heat dissipation load of the condenser does not need to be so large, avoiding energy waste caused by only one heat dissipation mode.

[0030] 3. By significantly improving the heat dissipation efficiency of the condenser, a loop heat pipe with multiple evaporators can be connected to one condenser, solving the problems of cooling multiple heat sources and long-distance heat transport. Only one condenser is needed to meet the simultaneous heat dissipation needs of multiple evaporators, ensuring the overall miniaturization of the loop heat pipe while maintaining high condensation efficiency. This makes it suitable for a wider range of applications and meets the requirements of electronic devices and equipment for miniaturization of loop heat pipes. When an evaporator is not working, some steam flows into the inactive evaporator, allowing it to also play a role in heat dissipation, reducing the workload of the condenser and accelerating heat dissipation.

[0031] 4. The loop heat pipe of the present invention has a liquid wick A in its evaporator A with an ingeniously designed novel structure. The liquid wick divides the evaporator cavity into an air outlet end A and a liquid suction end A. The liquid storage tank A provided at the liquid suction end A can store heat exchange medium, ensuring that there is always sufficient heat exchange medium in the liquid wick A, preventing the liquid wick A from being burned out. The liquid storage tank A plays the role of a liquid reservoir in the loop heat pipe, so that the loop heat pipe of the present invention can operate normally without a separate liquid reservoir, further reducing the overall volume of the loop heat pipe and realizing miniaturization of the loop heat pipe; a plurality of liquid channels A are provided on the liquid wick A to guide the heat exchange medium in the liquid storage tank A to enter the interior of the liquid wick A through the liquid channels A at a faster speed; a top gas channel and a plurality of intermediate gas channels are provided inside the liquid wick A, which greatly increases the evaporation surface of the liquid wick A. Steam can also quickly circulate to the gas pipeline through the numerous gas channels provided inside, thereby accelerating the evaporation heat exchange rate, greatly improving the heat exchange efficiency, and solving the problems of liquid backflow difficulty and gas accumulation in the heat pipe that easily lead to system startup failure.

[0032] 5. The design of the wick B in the evaporator B is ingenious. Its liquid reservoir B can store heat exchange medium, ensuring that there is always sufficient heat exchange medium in the wick B, preventing the wick B from burning out. The liquid reservoir B functions as a liquid reservoir in the loop heat pipe, allowing the loop heat pipe of the present invention to operate normally without a separate liquid reservoir, further reducing the overall volume of the loop heat pipe and achieving miniaturization of the loop heat pipe. A number of hollow cylindrical liquid channels B are provided on the wick B to guide the liquid reservoir B to quickly flow into the liquid channels B. Since the liquid channels B are arranged in multiple arrays, the evaporation surface of the wick is greatly increased. The liquid evaporates quickly through the columns of the liquid channels B, and the resulting vapor circulates in the space between the liquid channels B and enters the gas pipeline from the vapor outlet, forming a cycle, accelerating the evaporation heat exchange rate and greatly improving the heat exchange efficiency.

[0033] The loop heat pipe with multiple evaporators and a single condenser of the present invention realizes a loop heat pipe in which one condenser drives multiple evaporators through an ingeniously designed and rationally structured new condenser and evaporator structure, thereby ensuring heat dissipation efficiency while meeting miniaturization requirements. It can be flexibly installed according to the number and position of heating elements, and different heat dissipation modes can be selected according to the requirements of different heat dissipation loads to avoid energy waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the polygonal star-shaped fin microchannel condenser of the present invention;

[0035] Figure 2 yes Figure 1 Schematic diagram of the three-dimensional structure of the condenser;

[0036] Figure 3 yes Figure 1 Cross-section of the middle AA;

[0037] Figure 4 yes Figure 1 A schematic diagram of the three-dimensional structure of the hollow cylindrical fins in the steam chamber of the condenser;

[0038] Figure 5 It is a schematic diagram of the three-dimensional structure of a loop heat pipe of the present invention;

[0039] Figure 6 It is a schematic diagram of the three-dimensional structure of another loop heat pipe of the present invention;

[0040] Figure 7 Schematic diagram of the three-dimensional structure of the evaporator A of the loop heat pipe of the present invention;

[0041] Figure 8 yes Figure 7 Schematic diagram of the three-dimensional structure of the liquid wick A in the evaporator A;

[0042] Figure 9 yes Figure 8 Cross-section of the middle AA;

[0043] Figure 10 yes Figure 8 A schematic diagram of the three-dimensional structure of the liquid wick A;

[0044] Figure 11 yes Figure 8 A right side view of the wick A from the wicking end A;

[0045] Figure 12 Schematic diagram of the three-dimensional structure of the evaporator B of the loop heat pipe of the present invention;

[0046] Figure 13 yes Figure 12 Schematic diagram of the three-dimensional structure of the liquid wick B in the evaporator B;

[0047] The elements or structures represented by the reference numerals are:

[0048] Condenser 1, first baffle 11, second baffle 12, third baffle 13, fourth baffle 14, upper cooling fluid chamber 15, first cooling fluid outlet 15a, steam chamber 16, steam inlet 16a, heat exchange chamber 17, second cooling fluid inlet 17a, second cooling fluid outlet 17b, outer tube 171, inner tube 172, channel baffle 173, microchannel 174, vent 175, electric fan 176, baffle 177, condensate chamber 18, condensate outlet 18a, lower cooling fluid chamber 19, first cooling fluid inlet 19a;

[0049] Gas pipeline 3, liquid pipeline 4, liquid reservoir 5, and liquid replenishment pipeline 6;

[0050] Evaporator A2, liquid wick A21, heating surface A211, extended surface 211a, gas outlet A212, liquid wick A213, liquid storage tank A213a, steam channel 214, top gas channel 215, middle gas channel 216, liquid wick chip 217, liquid channel A217a, evaporator gas chamber A22, evaporator liquid chamber A23;

[0051] Evaporator B7, liquid absorption core B71, liquid partition plate 711, heat block 712, liquid channel B713, enclosure 714, evaporator liquid chamber B72, condensate inlet 72a, evaporator gas chamber B73, steam outlet 73a, liquid storage tank B74. DETAILED DESCRIPTION

[0052] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0053] Example 1 A polygonal star-shaped fin microchannel condenser

[0054] like Figure 1-4 A polygonal star-shaped fin microchannel condenser is shown. The main body of the condenser 1 is a rectangular parallelepiped. The interior of the main body is provided with a first baffle 11, a second baffle 12, a third baffle 13, and a fourth baffle 14 from top to bottom. The inner cavity of the main body is divided into an upper cooling fluid chamber 15, a steam chamber 16, a heat exchange chamber 17, a condensate chamber 18, and a lower cooling fluid chamber 19 from top to bottom. The upper cooling fluid chamber 15 is provided with a first cooling fluid outlet 15a, the lower cooling fluid chamber 19 is provided with a first cooling fluid inlet 19a, the heat exchange chamber 17 is provided with a second cooling fluid inlet 17a and a second cooling fluid outlet 17b, the steam chamber 16 is provided with a steam inlet 16a, and the condensate chamber 18 is provided with a condensate outlet 18a.

[0055] The heat exchange chamber 17 is provided with a plurality of hollow cylindrical fins arranged in a determinant pattern. The hollow cylindrical fins include a sleeved outer tube 171 and an inner tube 172. The interior of the inner tube 172 serves as a cooling fluid microchannel for the circulation of the cooling fluid, and the space between the outer tube 171 and the inner tube 172 serves as a steam channel for the circulation of steam. The cross-section of the outer tube 171 is a polygonal star. A plurality of channel baffles 173 are provided between the outer tube 171 and the inner tube 172 to divide the steam channel into a plurality of vertically extending microchannels 174. One end of the channel baffle 173 is connected to the outer tube 171, and the other end is connected to the inner tube 172, so that each convex corner of the polygonal star-shaped outer tube 171 and the space between the inner tube 172 form a corresponding microchannel 174. The hollow cylindrical fins in adjacent columns and rows are staggered.

[0056] The top end of the outer tube 171 of the hollow cylindrical fin is connected to the second partition 12, and the bottom end is connected to the third partition 13. Through holes are provided at the connection points of the second partition 12 and the third partition 13 with the outer tube 171, so that the outer tube 171 is connected to the steam chamber 16 and the condensate chamber 18 respectively.

[0057] The top end of the inner tube 172 of the hollow cylindrical fin extends upward beyond the outer tube 171 to connect with the first baffle 11, and the bottom end extends downward beyond the bottom end of the outer tube 171 to connect with the fourth baffle 14. Through holes are provided at the locations where the first baffle 11 and the fourth baffle 14 connect with the inner tube 172, so that the inner tube 172 communicates with the upper cooling fluid cavity 15 and the lower cooling fluid cavity 19, respectively.

[0058] Several ventilation windows 175 are provided on two opposing side walls of the heat exchange chamber 17. One of the side walls is also equipped with an electric fan 176 for blowing cool air into the heat exchange chamber 17 to dissipate heat. Baffles 177 are provided around the side wall where the electric fan 176 is located to enclose the electric fan 176. The ventilation windows 175 can be opened or closed as needed, using conventional opening and closing methods such as snap-fitting. When natural convection or air cooling mode is selected as the heat dissipation mode, the ventilation windows 175 are opened. When liquid cooling mode is selected, in which a cooling fluid circulates through the heat exchange chamber 17, the ventilation windows 175 are closed.

[0059] In some embodiments, a fan bracket is provided on the side wall of the heat exchange chamber 17 where the electric fan 176 is provided, for installing the electric fan 176, and the electric fan 176 is electrically connected to an external power supply.

[0060] In the polygonal star-shaped fin microchannel condenser of the present invention, the cooling fluid not only flows around the periphery of the fins in the heat exchange cavity for heat exchange, but also circulates within the inner tubes of the fins. This allows steam flowing through the outer tubes to exchange heat with the cooling fluid both inside and outside, significantly improving heat exchange efficiency. The inner tubes extend upward to connect with the upper cooling fluid cavity and downward to connect with the lower cooling fluid cavity. By setting the inner and outer tubes at different lengths, the inner and outer tubes are connected to different cavities, ensuring that both the inner and outer sides of the outer tubes are in contact with the cooling fluid for heat exchange.

[0061] Example 2 A multi-evaporator loop heat pipe based on multi-mode high-efficiency condensation (evaporator is evaporator A)

[0062] like Figure 5 A multi-evaporator loop heat pipe based on multi-mode high-efficiency condensation is shown, comprising a plurality of gas pipelines 3, a plurality of liquid pipelines 4, a plurality of evaporators 2 and the condenser 1 of Example 1;

[0063] The multiple evaporators 2 are connected in parallel to the steam chamber 16 of the condenser 1 via multiple gas pipelines 3 , and the multiple evaporators 2 are also connected in parallel to the condensate chamber 18 of the condenser 1 via multiple liquid pipelines 4 .

[0064] In some embodiments, the multi-evaporator loop heat pipe of the present invention further includes a liquid reservoir 5, which is connected to multiple liquid pipelines 4 through multiple liquid replenishment lines 6. The liquid replenishment lines 6 transport the liquid in the liquid reservoir 5 to the liquid pipeline 4 and then into the evaporator 2 for liquid compensation.

[0065] In some embodiments, the evaporator is evaporator A2, such as Figure 7-11 As shown, the evaporator A2 includes an evaporator shell A and a liquid wick A21. The liquid wick A21 is arranged in the middle of the evaporator shell A, dividing the two ends of the inner cavity of the evaporator A2 into an evaporator gas cavity A22 and an evaporator liquid cavity A23.

[0066] The main body of the liquid absorbent core A21 is in the shape of a rectangular parallelepiped, with the bottom surface of the main body being the heating surface A211, the left side being the air outlet end A212, and the right side being the liquid suction end A213; the right side of the liquid absorbent core A21 is recessed inward to form a liquid storage tank A213a; a plurality of steam channels 214 parallel to the heating surface A211 are provided on the outer surfaces of the front and rear sides of the liquid absorbent core A21, one end of the steam channel 214 reaches the air outlet end A212 and is connected to the evaporator gas cavity A22, and the other end is spaced apart from the liquid suction end A213, so that the steam channel 214 is separated from the evaporator liquid cavity A23 and is not connected; the heating surface A211 of the liquid absorbent core A21 extends toward the evaporator gas cavity A22 to form an extended surface 211a, which is used to cover the surface of the evaporator gas cavity A22 in contact with the heating element;

[0067] A top gas channel 215 and several intermediate gas channels 216 are provided inside the liquid wick A21. The top gas channel 215 and the intermediate gas channels 216 extend from the gas outlet end A212 to the liquid wick A213, and a distance is left between the top gas channel 215 and the intermediate gas channels 216 and the evaporator liquid chamber A23. This prevents the heat exchange medium liquid from entering the gas channel, which reduces the amount of liquid entering the liquid wick A21 and reduces the evaporation rate and heat exchange efficiency. The intermediate gas channels 216 extend vertically from the top to the bottom surface of the liquid wick A21 and are arranged parallel to the front and rear side surfaces of the liquid wick A21. The top gas channel 215 extends between the front and rear side surfaces of the liquid wick A21 and is connected to the intermediate gas channels 216.

[0068] The intermediate gas channel 216 separates the part of the liquid wick A21 close to the gas outlet end A212 into a number of liquid wick chips 217 parallel to the front and rear sides of the liquid wick A21. The liquid wick chip 217 is provided with a number of liquid channels A217a parallel to the heating surface A211 from top to bottom. One end of the liquid channel A217a extends to the liquid storage tank A213a and is connected to the evaporator liquid cavity A23, and the other end is spaced apart from the gas outlet end A212, so that the liquid channel A217a is separated from the evaporator gas cavity A22 and is not connected, thereby preventing the heat exchange working medium liquid from entering the evaporator gas cavity A22, resulting in a reduction in the liquid entering the liquid wick A21, thereby reducing the evaporation rate and heat exchange efficiency.

[0069] In some embodiments, the top of the liquid-absorbing chip 217 is in the shape of an arc curve.

[0070] In some embodiments, the number of evaporators is four, and the outer tubes 171 of the hollow cylindrical fins are in the shape of a hexagonal star.

[0071] The working process of the loop heat pipe of this embodiment is as follows:

[0072] When the evaporator A2 starts heating, the liquid in the wick A21 is heated and evaporated into gas, which enters the steam chamber 16 of the condenser 1 through the gas pipeline 3 and exchanges heat through the heat exchange chamber 17. In the condenser 1, the steam condenses into liquid and enters the condensation liquid chamber 18. Due to capillary action, it flows into the liquid storage tank A213a of the evaporator A2 through the liquid pipeline 4. The heat exchange working fluid liquid fills the wick A21, is heated into steam by the heat of the heating element, and enters the gas pipeline 3, forming a cycle.

[0073] A liquid reservoir 5 can also be connected. The liquid reservoir 5 is separated from the evaporator A2 and is connected to the liquid pipeline 4 and the evaporator A2 through the liquid replenishment pipeline 6. It is used to store excess heat exchange medium and replenish the liquid in the evaporator A2. The circulation of the medium is driven by the capillary pressure generated by the evaporator liquid absorption core A21, and no external power is required.

[0074] Example 3 A multi-evaporator loop heat pipe based on multi-mode high-efficiency condensation (evaporator is evaporator B)

[0075] Another multi-evaporator loop heat pipe based on multi-mode high-efficiency condensation of the present invention comprises a plurality of gas pipelines 3, a plurality of liquid pipelines 4, a plurality of evaporators 7 and the condenser 1 of embodiment 1;

[0076] The multiple evaporators 7 are connected in parallel to the steam chamber 16 of the condenser 1 through the multiple gas pipelines 3 , and the multiple evaporators 7 are also connected in parallel to the condensate chamber 18 of the condenser 1 through the multiple liquid pipelines 4 .

[0077] In some embodiments, the multi-evaporator loop heat pipe of the present invention further comprises a liquid reservoir 5, such as Figure 6As shown, the liquid reservoir 5 is connected to the multiple liquid pipelines 4 through multiple liquid replenishing pipelines 6. The liquid replenishing pipelines 6 transport the liquid in the liquid reservoir 5 to the liquid pipeline 4 and then into the evaporator 7 for liquid compensation.

[0078] Among them, the evaporator is evaporator B7, such as Figure 12-13 As shown, the evaporator B7 includes an evaporator shell B and a liquid wick B71. The liquid wick B71 includes a liquid barrier plate 711 at the top and a heat receiving block 712 at the bottom. A plurality of hollow cylindrical liquid channels B713 arranged in an array are provided between the liquid barrier plate 711 and the heat receiving block 712. One end of the liquid channel B713 is connected to the liquid barrier plate 711, and the other end is connected to the heat receiving block 712.

[0079] The wick B71 is disposed within the evaporator housing B. The size of the liquid barrier plate 711 matches that of the evaporator housing B, dividing the top of the evaporator housing B into an evaporator liquid chamber B72 capable of storing condensed liquid. A through hole is provided on the liquid barrier plate 711 at the connection with the liquid channel B713, thereby connecting the evaporator liquid chamber B72 with the liquid channel B713.

[0080] The heat receiving block 712 contacts the bottom surface of the evaporator shell B for receiving heat conducted by the heating element; the middle cavity inside the evaporator shell B serves as the evaporator gas cavity B73, and the cavity of the evaporator gas cavity B73 is provided with a steam outlet 73a for connecting to the gas pipeline 3, and the cavity of the evaporator liquid cavity B72 is provided with a condensate inlet 72a for connecting to the liquid pipeline 4.

[0081] In some embodiments, a surrounding plate 714 is provided around the liquid barrier plate 711 to enclose the top of the liquid absorbent core B71 to form a liquid storage tank B74.

[0082] In some embodiments, a distance is left between the side wall of the evaporator shell B where the steam outlet 73a is provided and the liquid channel B713 to accelerate the flow of steam.

[0083] In some embodiments, the number of evaporators is four, and the outer tubes 171 of the hollow cylindrical fins are in the shape of a hexagonal star.

[0084] The working process of the loop heat pipe of this embodiment is as follows:

[0085] When the evaporator B7 starts heating, the liquid in the wick B71 is heated and evaporated into gas, which enters the steam chamber 16 of the condenser 1 through the gas pipeline 3 and flows through the heat exchange chamber 17 for heat exchange. In the condenser 1, the steam condenses into liquid and enters the condensation liquid chamber 18. Due to capillary action, it flows into the liquid storage tank B74 of the evaporator B7 through the liquid pipeline 4. The heat exchange working fluid liquid fills the wick B71, is heated into steam by the heat of the heating element, and enters the gas pipeline 3, forming a cycle.

[0086] A liquid reservoir 5 can also be connected. The liquid reservoir 5 is separated from the evaporator B7 and is connected to the liquid pipeline 4 and the evaporator B7 through the liquid replenishment line 6. It is used to store excess heat exchange medium and replenish the liquid in the evaporator B7. The circulation of the medium is driven by the capillary pressure generated by the evaporator liquid absorption core B71, and no external power is required.

[0087] The loop heat pipe with multiple evaporators and a single condenser of the present invention realizes a loop heat pipe in which one condenser drives multiple evaporators through an ingeniously designed and rationally structured new condenser and evaporator structure, thereby ensuring heat dissipation efficiency while meeting miniaturization requirements. It can be flexibly installed according to the number and position of heating elements, and different heat dissipation modes can be selected according to the requirements of different heat dissipation loads to avoid energy waste.

Claims

1. A polygonal star-shaped fin microchannel condenser, characterized in that: The main body of the condenser (1) is in the shape of a rectangular parallelepiped. A first partition (11), a second partition (12), a third partition (13) and a fourth partition (14) are provided inside the main body from top to bottom, and the inner cavity of the main body is divided into an upper cooling fluid cavity (15), a steam cavity (16), a heat exchange cavity (17), a condensate cavity (18) and a lower cooling fluid cavity (19) in sequence from top to bottom. The upper cooling fluid cavity (15) is provided with a first cooling fluid outlet (15a), the lower cooling fluid cavity (19) is provided with a first cooling fluid inlet (19a), the heat exchange cavity (17) is provided with a second cooling fluid inlet (17a) and a second cooling fluid outlet (17b), the steam cavity (16) is provided with a steam inlet (16a), and the condensate cavity (18) is provided with a condensate outlet (18a). A plurality of hollow columnar fins arranged in a determinant are provided in the heat exchange cavity (17), wherein the hollow columnar fins include a sleeved outer tube (171) and an inner tube (172), the interior of the inner tube (172) serves as a cooling fluid microchannel for the circulation of the cooling fluid, and the space between the outer tube (171) and the inner tube (172) serves as a steam channel for the circulation of steam; the cross section of the outer tube (171) is a polygonal star, and a plurality of channel partitions (173) are provided between the outer tube (171) and the inner tube (172) to divide the steam channel into a plurality of vertically penetrating microchannels (174); one end of the channel partition (173) is connected to the outer tube (171), and the other end is connected to the inner tube (172), so that each convex corner of the polygonal star-shaped outer tube (171) and the space between the inner tube (172) constitute a corresponding microchannel (174); the hollow columnar fins of adjacent columns and adjacent rows are staggered; The top end of the outer tube (171) of the hollow columnar fin is connected to the second partition (12), and the bottom end is connected to the third partition (13). Through holes are provided at the locations where the second partition (12) and the third partition (13) are connected to the outer tube (171), so that the outer tube (171) is communicated with the steam chamber (16) and the condensate chamber (18) respectively. The top end of the inner tube (172) of the hollow columnar fin exceeds the outer tube (171) and extends upward to connect with the first partition (11), and the bottom end exceeds the bottom end of the outer tube (171) and extends downward to connect with the fourth partition (14). Through holes are provided at the places where the first partition (11) and the fourth partition (14) are connected to the inner tube (172), so that the inner tube (172) is communicated with the upper cooling fluid cavity (15) and the lower cooling fluid cavity (19) respectively. A plurality of ventilation windows (175) are provided on two opposite side walls of the heat exchange chamber (17), one of the side walls is further provided with an electric fan (176) for blowing cool air into the heat exchange chamber (17) to dissipate heat, and baffles (177) are provided around the side wall where the electric fan (176) is provided to surround the electric fan (176) in the middle.

2. The condenser according to claim 1, characterized in that: A fan bracket is provided on the side wall of the heat exchange chamber (17) on which the electric fan (176) is provided, and is used to install the electric fan (176). The electric fan (176) is electrically connected to an external power supply.

3. A loop heat pipe based on multi-mode high-efficiency condensation, characterized by: The condenser (1) comprises a plurality of gas pipelines (3), a plurality of liquid pipelines (4), a plurality of evaporators and the condenser (1) according to claim 1 or 2; the plurality of evaporators are connected in parallel with the steam chamber (16) of the condenser (1) through the plurality of gas pipelines (3), and the plurality of evaporators are also connected in parallel with the condensation liquid chamber (18) of the condenser (1) through the plurality of liquid pipelines (4).

4. The loop heat pipe based on multi-mode high-efficiency condensation according to claim 3, characterized in that: The loop heat pipe further comprises a liquid reservoir (5), wherein the liquid reservoir (5) is respectively connected to the plurality of liquid pipelines (4) via a plurality of liquid replenishing pipelines (6), and the liquid replenishing pipelines (6) transport the liquid in the liquid reservoir (5) to the liquid pipeline (4) and then into the evaporator for liquid compensation.

5. The loop heat pipe based on multi-mode high-efficiency condensation according to claim 3, characterized in that: The evaporator is an evaporator A (2), and the evaporator A (2) includes an evaporator shell A and a liquid wick A (21), wherein the liquid wick A (21) is arranged in the middle of the evaporator shell A, and separates the two ends of the inner cavity of the evaporator A (2) into an evaporator gas cavity A (22) and an evaporator liquid cavity A (23); The main body of the liquid absorbing core A (21) is in the shape of a rectangular parallelepiped, the bottom surface of the main body is the heating surface A (211), the left side surface is the air outlet end A (212), and the right side surface is the liquid absorbing end A (213); the right side surface of the liquid absorbing core A (21) is recessed inward to form a liquid storage tank A (213a); a plurality of steam channels (214) parallel to the heating surface A (211) are provided on the outer surfaces of the front and rear sides of the liquid absorbing core A (21), one end of the steam channel (214) reaches the air outlet end A (212) and is connected to the evaporator gas cavity A (22), and the other end is spaced apart from the liquid absorbing end A (213); the heating surface A (211) of the liquid absorbing core A (21) extends toward the evaporator gas cavity A (22) to form an extended surface (211a) for covering the surface of the evaporator gas cavity A (22) in contact with the heating element; A top gas channel (215) and a plurality of intermediate gas channels (216) are provided inside the liquid absorbent core A (21), wherein the top gas channel (215) and the intermediate gas channels (216) extend from the gas outlet end A (212) to the liquid absorbent end A (213), and a distance is left between the liquid absorbent end A (213); the intermediate gas channels (216) pass through from the top surface to the bottom surface of the liquid absorbent core A (21) and are arranged parallel to the front and rear side surfaces of the liquid absorbent core A (21); the top gas channel (215) passes through between the front and rear side surfaces of the liquid absorbent core A (21) and is in communication with the intermediate gas channels (216); The intermediate gas channel (216) divides the portion of the liquid wick A (21) close to the gas outlet end A (212) into a plurality of liquid wick chips (217) parallel to the front and rear sides of the liquid wick A (21). The liquid wick chip (217) is provided with a plurality of liquid channels A (217a) parallel to the heating surface A (211) from top to bottom. One end of the liquid channel A (217a) extends to the liquid storage tank A (213a) and is connected to the evaporator liquid chamber A (23), while the other end is spaced apart from the gas outlet end A (212).

6. The loop heat pipe based on multi-mode high-efficiency condensation according to claim 5, characterized in that: The top of the liquid absorbing chip (217) is in the shape of an arc surface.

7. The loop heat pipe based on multi-mode high-efficiency condensation according to claim 3, characterized in that: The evaporator is an evaporator B (7), and the evaporator B (7) includes an evaporator shell B and a liquid wick B (71), and the liquid wick B (71) includes a liquid partition plate (711) at the top and a heat receiving block (712) at the bottom; a plurality of hollow columnar liquid channels B (713) arranged in an array are provided between the liquid partition plate (711) and the heat receiving block (712), and one end of the liquid channel B (713) is connected to the liquid partition plate (711), and the other end is connected to the heat receiving block (712); The liquid wick B (71) is arranged in the evaporator shell B. The size of the liquid partition plate (711) matches the size of the evaporator shell B. The top of the evaporator shell B is partitioned into an evaporator liquid chamber B (72) capable of storing condensed liquid. A through hole is provided at the location where the liquid partition plate (711) is connected to the liquid channel B (713), so that the evaporator liquid chamber B (72) and the liquid channel B (713) are in communication. The heat receiving block (712) contacts the bottom surface of the evaporator shell B and is used to receive heat conducted by the heating element; the middle cavity in the evaporator shell B serves as the evaporator gas cavity B (73), and the cavity of the evaporator gas cavity B (73) is provided with a steam outlet (73a) for connecting to the gas pipeline (3), and the cavity of the evaporator liquid cavity B (72) is provided with a condensate inlet (72a) for connecting to the liquid pipeline (4).

8. The loop heat pipe based on multi-mode high-efficiency condensation according to claim 7, characterized in that: The liquid isolation plate (711) is surrounded by surrounding plates (714) to enclose the top of the liquid absorbent core B (71) to form a liquid storage tank B (74).

9. The loop heat pipe based on multi-mode high-efficiency condensation according to claim 7, characterized in that: A distance is left between the side wall of the evaporator shell B provided with the steam outlet (73a) and the liquid channel B (713), thereby accelerating the flow of steam.

10. The loop heat pipe based on multi-mode high-efficiency condensation according to claim 3, characterized in that: The number of the evaporators is 4, and the outer tube (171) of the hollow columnar fin is in the shape of a hexagonal star.

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