CN110030860B - Double-lead-tube type double-liquid-reservoir loop heat pipe - Google Patents
Double-lead-tube type double-liquid-reservoir loop heat pipe Download PDFInfo
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- CN110030860B CN110030860B CN201910401153.XA CN201910401153A CN110030860B CN 110030860 B CN110030860 B CN 110030860B CN 201910401153 A CN201910401153 A CN 201910401153A CN 110030860 B CN110030860 B CN 110030860B
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- liquid
- heat pipe
- reservoir
- loop heat
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/04—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with tubes having a capillary structure
- F28D15/043—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with tubes having a capillary structure forming loops, e.g. capillary pumped loops
Abstract
A double-lead-tube type double-liquid-reservoir loop heat pipe belongs to the technical field of electronic equipment heat control. The device is basically characterized by comprising an evaporator, a liquid storage device 1, a liquid storage device 2, a liquid guide pipe 1, a liquid guide pipe 2, a condenser, a steam pipeline, a liquid pipeline and the like. The defects of the prior art are overcome, the double-lead-tube type double-liquid-reservoir loop heat pipe is provided, and a detailed solution is provided for the heat dissipation requirement under the condition that the posture of the electronic equipment is constantly changed under the gravity field and overload environment. Through the structural design of two pipes, improve the cooling effect of backward flow liquid to two reservoirs, improve the startability of two reservoir loop heat pipes, realize the high-efficient steady operation of electronic equipment cooling system full gesture in the gravity field.
Description
Technical Field
The invention relates to a double-guide-tube double-reservoir loop heat pipe, and belongs to the technical field of heat control of electronic equipment.
Background
Modern microelectronic technology is developing towards high power, high integration and miniaturization, resulting in continuous increase of heat flux density required to be dissipated by electronic equipment, increasingly prominent heat dissipation problem, and becoming a key factor influencing the operation performance and reliability of the electronic equipment. Aviation aircrafts such as fighters generally need to perform high maneuvering actions such as rolling, climbing and diving, and airborne electronic equipment is in a variable attitude overload environment, so that the high-efficiency heat dissipation of the electronic equipment is challenged seriously. The traditional heat dissipation technology is large in size/quality such as air cooling and single-phase liquid cooling, the whole heat dissipation efficiency is not high, and the novel heat dissipation technology which is more energy-saving and efficient and can effectively deal with overload environments needs to be developed urgently.
A Heat Pipe (HP) is known as a "superconductor" in the field of Heat transfer as a two-phase Heat transfer device. The heat is transferred by utilizing the evaporation/condensation phase change of the working medium, the working medium is driven to circulate by utilizing the capillary pressure generated by the capillary core of the evaporator without external power, and the heat exchanger is widely applied to the aspects of spacecraft thermal control, modern electronic equipment cooling and the like. As a new generation of Heat Pipe, a Loop Heat Pipe (LHP) has advantages of a conventional Heat Pipe, overcomes disadvantages of the conventional Heat Pipe limited by a transmission distance and a direction of a cold and Heat source, has characteristics of large Heat transmission, long transmission distance, high temperature control precision, strong antigravity capability, small volume, light weight, and the like, and is receiving increasingly wide attention in aspects of aerospace thermal management, Heat dissipation of high Heat flux density electronic devices, and the like. Although the loop heat pipe has been successfully applied to the field of spacecraft thermal control and ground electronic equipment cooling, the technical development is mature, but the loop heat pipe with the conventional structure is limited by the relative positions of the evaporator and the liquid storage device due to the liquid supply problem of the evaporator capillary core when the loop heat pipe works in a ground gravity field or an acceleration field. Once the loop heat pipe is in an unfavorable posture, the loop heat pipe cannot be started and operated normally. The problems that arise from this are: the electronics on aerospace vehicles tend to experience accelerations of different magnitudes from various directions. Under the overload acceleration environment, the acceleration effect can cause the loop heat pipe to fail to work normally, so that the electronic equipment is burnt due to overheating.
Before a conventional single-liquid-reservoir loop heat pipe runs, a starting process needs to be completed firstly, and due to the difference of gas-liquid distribution in a liquid main channel and a steam channel of an evaporator, the loop heat pipe is generally provided with four starting modes, so that the starting time, the starting temperature rise and the like can be influenced. The root cause of the loop heat pipe being able to start is that a sufficient temperature difference can be created between the evaporator and the reservoir, and the heat leak from the evaporator to the reservoir can be balanced by the returning subcooled liquid. The evaporator/reservoir coupling design allows the loop heat pipe to be compact and does not require any pre-treatment prior to start-up. However, in the existing evaporator structure, due to the arrangement of the liquid trunk, heat leakage from the evaporator to the liquid reservoir is serious, and serious adverse effect is generated on the working performance of the loop heat pipe. In addition, when the heat load is small, the loop heat pipe generally operates in the variable heat conduction region, most regions of the condenser are occupied by the supercooled liquid and are not effectively utilized, and the cooling effect of the heat sink cannot be normally exerted, so that the operating temperature of the loop heat pipe is obviously higher, and a series of unstable working phenomena such as temperature fluctuation, working medium backflow, temperature hysteresis and the like can occur under certain conditions.
As shown in fig. 1, a traditional double-reservoir Loop Heat Pipe (DCCLHP) is developed on the basis of a single-reservoir Loop Heat Pipe, and two reservoirs are respectively arranged at two ends of an evaporator, so that the problem of capillary core liquid supply of the Loop Heat Pipe in different postures is solved ingeniously. However, since the conventional dual-reservoir loop heat pipe is provided with only one liquid lead pipe and penetrates through one reservoir, when the dual-reservoir loop heat pipe is in an unfavorable posture (the reservoir without the penetration of the liquid lead pipe is positioned above), the dual-reservoir loop heat pipe cannot be started under a small heat load, and the steady-state operation temperature in a certain heat load range is obviously increased. Fig. 2-4 are diagrams of the system in horizontal and vertical positions, respectively. When the evaporator/liquid storage device is vertically placed, as shown in fig. 3 and 4, the upper liquid storage device cannot be filled with liquid, and due to buoyancy, steam generated in the liquid main channel moves upwards, so that heat leakage of the evaporator to the upper liquid storage device is increased; the situation with the reservoir 1 on top (fig. 3) at this time differs significantly from the situation with the reservoir 2 on top (fig. 4). In fig. 3, the liquid conduit passing through the reservoir 2(4) has a significant cooling effect on the reservoir 2, and the system is easy to start. In fig. 4, the supercooled liquid in the liquid guide tube (5) enters the liquid main channel to supply liquid to the capillary core, and rarely enters the liquid reservoir 1(1), and the supercooled liquid in the liquid guide tube (5) is subjected to the on-way heating effect, so that the supercooling degree when the supercooled liquid reaches the liquid reservoir 1(1) is obviously reduced, the cooling effect of the returned supercooled liquid on the liquid reservoir 1(1) is poor, a large temperature difference is difficult to form between the evaporator (2) and the liquid reservoir 1(1) under a small heat load, and finally the start failure is caused. In order to solve the key problem, the project provides a double-leading-tube type double-liquid-reservoir loop heat pipe, so that the cooling effect of backflow liquid on two liquid reservoirs under the conditions of different postures of a gravity field or an overload environment is effectively improved, and the starting problem of the double-liquid-reservoir loop heat pipe under the unfavorable posture is further solved.
Disclosure of Invention
The technical problem solved by the invention is as follows: the defects of the prior art are overcome, the double-lead-tube type double-liquid-reservoir loop heat pipe is provided, and a detailed solution is provided for the heat dissipation requirements of electronic equipment in different postures in a gravity field or overload environment. Through the structural design of two guide pipes, effectively improve the cooling effect of reflux liquid to two reservoir under the different gesture circumstances under gravity field or overload environment, make two reservoir loop heat pipes can start smoothly at gravity field or different gestures homoenergetic under the overload environment, realize the high-efficient operation of the wide load of two reservoir loop heat pipes gravity field full gesture.
The technical scheme of the invention is as follows:
a double-lead-tube type double-liquid-reservoir loop heat pipe is basically characterized by comprising a liquid reservoir 1, a liquid lead tube 1, an evaporator, a capillary wick, a liquid reservoir 2, a liquid lead tube 2, a liquid pipeline, a condenser, a cold plate and a steam pipeline.
According to the requirements of use temperature, pressure, material compatibility, heat transfer capacity and the like, different working media are selected, and common working media such as water, ammonia, acetone, Freon and the like are selected.
The liquid storage device and the evaporator are fixed together through electron beams or other welding modes, and then end covers and liquid guide pipes on two sides of the liquid storage device are installed, so that the liquid storage device, the evaporator and the liquid guide pipes are connected.
The outlet on the evaporator shell is connected with a steam pipeline and is connected together through argon arc welding. The outlet of the steam pipeline is connected with the inlet of the condenser and is connected together through argon arc welding.
The condenser pipeline and the condenser are connected together in a welding mode, and the heat dissipation mode of the cold plate is selected according to the requirement of heat transfer power, and natural convection, forced convection and the like are generally available.
The outlet of the condenser is connected with the inlet of the liquid pipeline and is connected together through argon arc welding. The outlet of the liquid pipeline is divided into two branches through a tee joint, and the two branches are respectively connected with the two liquid leading pipes and are connected together through argon arc welding.
The liquid leading pipes are respectively inserted into liquid main channels of the evaporator capillary wick, and the liquid leading pipes are connected with the end cover of the liquid storage device through welding.
After the whole system is connected and installed, the system is vacuumized, so that the internal cleanliness is ensured, and the influence of non-condensable gas is reduced; then a certain amount of working medium is filled, and the system can meet the heat dissipation requirements of different working conditions.
Compared with the prior art, the invention has the beneficial effects that:
in the technical scheme of the invention, the structural design of double guide pipes is adopted. By applying the double-liquid guide pipe, the backflow supercooled liquid is divided into two paths before entering the liquid reservoirs, and the two paths of backflow supercooled liquid respectively enter the two liquid reservoirs to efficiently cool the two liquid reservoirs. Experimental results prove that the scheme can ensure that the double-liquid-reservoir loop heat pipe can be smoothly started in any posture of a gravity field, and high-efficiency and stable operation is achieved. When the traditional single-lead-tube type double-reservoir loop heat pipe is in a state that a gravity field is unfavorable, the heat pipe cannot be started under a small heat load, and the steady-state operation temperature in a certain heat load range is obviously higher.
Drawings
FIG. 1 is a schematic diagram of a conventional dual reservoir loop heat pipe configuration;
FIG. 2 is a schematic view of a horizontal working attitude of a conventional dual reservoir loop heat pipe;
FIG. 3 is a schematic view of a conventional dual reservoir loop heat pipe in a vertical working attitude 1;
FIG. 4 is a schematic view of a vertical working attitude 2 of a conventional dual reservoir loop heat pipe;
FIG. 5 is a schematic diagram of a loop heat pipe structure of a double-lead-tube type double-reservoir loop heat pipe;
FIG. 6 is a schematic view of the horizontal working attitude of a loop heat pipe of a double-lead-type double-reservoir loop;
FIG. 7 is a schematic view of a vertical working posture 1 of a double-lead-tube type double-reservoir loop heat pipe;
fig. 8 is a schematic view of a vertical working posture 2 of a double-lead-tube type double-reservoir loop heat pipe.
Detailed Description
The invention relates to a heat dissipation problem for electronic equipment in different postures in a gravity field or overload environment, and according to a diagram 1, a conventional double-liquid-reservoir loop heat pipe comprises a liquid reservoir 1(1), an evaporator (2), a capillary core (3), a liquid reservoir 2(4), a liquid guide pipe (5), a liquid pipeline (6), a condenser (7), a cold plate (8) and a steam pipeline (9).
Because the conventional single-lead-tube type double-reservoir loop heat pipe is difficult to start under certain unfavorable postures, even starting cannot be realized. As shown in fig. 5, the technical scheme of the invention provides a double-lead-tube type double-reservoir loop heat pipe, and through the structural design of the double lead tubes, the cooling effect of backflow liquid on two reservoirs under different postures in a gravity field or an overload environment is effectively improved, so that the double-reservoir loop heat pipe can be smoothly started under different postures in the gravity field or the overload environment, and the full-posture wide-load efficient operation of the double-reservoir loop heat pipe in the gravity field is realized.
The specific implementation steps are as follows: firstly, according to the requirements of use temperature, pressure, material compatibility, heat transfer capacity and the like, different working media are selected, and common working media such as water, ammonia, acetone, Freon and the like are selected.
The liquid storage device 1(1), the liquid leading pipe 1(2), the evaporator (3), the capillary core (4), the liquid storage device 2(5), the liquid leading pipe 2(6), the liquid pipeline (7), the condenser (8), the cold plate (9) and the steam pipeline (10) are processed.
The loop heat pipe processed by machining, sintering and other processes is connected with the evaporator (3) and the capillary core (4) together for capillary force test, so that the evaporator shell and the capillary core are ensured to be tightly matched, and the capillary core is detected to be free from damage.
The liquid reservoirs 1(1), 2(5) and the evaporator (3) are fixed together by electron beams or other welding methods, and then end covers and liquid guide pipes on two sides of the liquid reservoirs are installed to connect the liquid reservoirs (1) (5), the evaporator (3) and the liquid guide pipes (2) (6).
The outlet on the shell of the evaporator (3) is connected with a steam pipeline (10) and is connected together through argon arc welding. The outlet of the steam pipeline (10) is connected with the inlet of the condenser (8) and is connected together through argon arc welding.
The condenser (8) and the cold plate (9) are connected together in a welding mode, and the heat dissipation mode of the cold plate (9) is selected according to the requirement of heat transfer power, and natural convection, forced convection and the like are generally available.
The outlet of the condenser (8) is connected with the inlet of the liquid pipeline (7) and is connected together through argon arc welding. The liquid pipeline (7) is divided into two branches by a tee joint, is respectively connected with the liquid leading pipes 1(2) and the liquid leading pipes 2(6) and is connected together by argon arc welding.
The liquid leading pipes (2) and (6) are respectively inserted into a liquid main channel of the evaporator capillary wick, and the liquid leading pipes and the end cover of the liquid storage device are connected together through welding.
After the whole system is connected and installed and before the whole system is put into operation, the system needs to be vacuumized (< 1 × 10)-2Pa), ensuring the cleanliness of the interior and reducing the influence of non-condensable gas; then a proper amount of working medium is filled in,the heat dissipation requirements of the system under different postures of fig. 6, 7, 8 and the like are ensured.
The foregoing is only a general embodiment of the present invention, and those skilled in the art can make various modifications and improvements without departing from the spirit of the present invention, and these modifications and improvements should be considered as within the scope of the present invention.
In the technical scheme of the invention, the structural design of double guide pipes is adopted. By applying the double-liquid guide pipe, the backflow supercooled liquid is divided into two paths before entering the liquid reservoirs, and the two paths of backflow supercooled liquid respectively enter the two liquid reservoirs to efficiently cool the two liquid reservoirs. Experimental results prove that the scheme can ensure that the double-liquid-reservoir loop heat pipe can be smoothly started in any posture in a gravity field or overload environment, and the double-liquid-reservoir loop heat pipe runs efficiently and stably. When the traditional single-lead-tube type double-reservoir loop heat pipe is in a state of being unfavorable in gravity field, the double-reservoir loop heat pipe cannot be started under a small load, and the steady-state operation temperature in a certain heat load range is obviously higher.
Claims (7)
1. A double-guide-tube double-liquid-reservoir loop heat pipe is characterized by comprising a liquid reservoir 1(1), a liquid guide tube 1(2), a cylindrical evaporator (3), a capillary core (4), a liquid reservoir 2(5), a liquid guide tube 2(6), a liquid pipeline (7), a condenser (8), a cold plate (9) and a steam pipeline (10); the liquid accumulators 1(1) and 2(5) are respectively positioned at two sides of the evaporator (3) and then form a loop with the condenser (8) through a steam pipeline (10) and a liquid pipeline (7); the liquid leading tube 1(2) and the liquid leading tube 2(6) respectively pass through the liquid storage device 1(1) and the liquid storage device 2(5) and enter the inner hole of the capillary core (4), and the liquid leading tube 1(2) and the liquid leading tube 2(6) are respectively coaxial with the liquid storage device 1(1) and the liquid storage device 2 (5).
2. The dual-riser-type dual-reservoir loop heat pipe as claimed in claim 1, wherein: the liquid reservoirs 1, 2 and 5 are both cylindrical, the outer diameter is not less than the diameter of the evaporator (3), and the liquid reservoirs and the evaporator (3) are coaxial.
3. The dual-riser-type dual-reservoir loop heat pipe as claimed in claim 1, wherein: a porous material capillary core (4) is nested in a shell of the evaporator (3), and the capillary core (4) is made of micron-level high-thermal-conductivity-coefficient metal powder.
4. The dual-riser-type dual-reservoir loop heat pipe as claimed in claim 1, wherein: the metal powder is copper powder, nickel powder or stainless steel powder.
5. The dual-riser-type dual-reservoir loop heat pipe as claimed in claim 1, wherein: the liquid reservoirs 1(1), 2(5) and the evaporator (3) are connected by electron beams or other welding methods.
6. The dual-riser-type dual-reservoir loop heat pipe as claimed in claim 1, wherein: the lengths of the vapor line (10) and the liquid line (7) are determined according to the transmission distance.
7. The dual-riser-type dual-reservoir loop heat pipe as claimed in claim 1, wherein: the condenser (8) is fixed on the cold plate (9) through brazing, and the heat dissipation mode of the cold plate (9) is natural convection or forced convection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910401153.XA CN110030860B (en) | 2019-05-15 | 2019-05-15 | Double-lead-tube type double-liquid-reservoir loop heat pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910401153.XA CN110030860B (en) | 2019-05-15 | 2019-05-15 | Double-lead-tube type double-liquid-reservoir loop heat pipe |
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| CN110030860A CN110030860A (en) | 2019-07-19 |
| CN110030860B true CN110030860B (en) | 2020-11-24 |
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| CN201910401153.XA Expired - Fee Related CN110030860B (en) | 2019-05-15 | 2019-05-15 | Double-lead-tube type double-liquid-reservoir loop heat pipe |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111386012B (en) * | 2020-02-28 | 2022-03-25 | 北京空间飞行器总体设计部 | Radiator with variable heat dissipation capacity suitable for near space |
| CN112964101A (en) * | 2021-02-26 | 2021-06-15 | 北京空间机电研究所 | Anti acceleration loop heat pipe |
| CN113613476A (en) * | 2021-09-15 | 2021-11-05 | 沈阳飞机设计研究所扬州协同创新研究院有限公司 | Loop heat pipe for cooling airborne electronic equipment |
| CN113758333B (en) * | 2021-09-24 | 2022-04-26 | 北京空间飞行器总体设计部 | Method and device for determining temperature control power of loop heat pipe and storage medium |
| CN114646234B (en) * | 2022-03-23 | 2023-07-21 | 北京航空航天大学 | Double-reservoir loop heat pipe with sequential cooling |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4365664A (en) * | 1980-10-20 | 1982-12-28 | Hughes Aircraft Company | Osmotically pumped heat pipe with passive mixing |
| BE1009410A3 (en) * | 1995-06-14 | 1997-03-04 | B C A Sa | Device heat transport. |
| JP2004190976A (en) * | 2002-12-12 | 2004-07-08 | Sony Corp | Heat transport device and electronic device |
| CN101013011A (en) * | 2007-02-05 | 2007-08-08 | 中山大学 | Multiple-pass self-regulating loop heat pipe device |
| CN101943531A (en) * | 2010-09-17 | 2011-01-12 | 中国科学院上海技术物理研究所 | Double-evaporator loop heat pipe sharing one compensator |
| CN103344143B (en) * | 2013-06-08 | 2015-05-20 | 北京航空航天大学 | Evaporator and liquid reservoir used for loop heat pipe and application thereof |
| CN105277028A (en) * | 2015-11-16 | 2016-01-27 | 中国电子科技集团公司第十研究所 | Thermal control loop heat pipe of integrated structure |
| EP3376148B1 (en) * | 2017-03-14 | 2019-09-11 | Allatherm SIA | Evaporator-reservoir modular unit |
| CN109798795B (en) * | 2018-11-28 | 2020-09-25 | 北京空间飞行器总体设计部 | Flat loop heat pipe with double liquid reservoirs |
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2019
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