CN111102865A - Metal-nonmetal composite capillary wick applied to loop heat pipe system and preparation method thereof - Google Patents
Metal-nonmetal composite capillary wick applied to loop heat pipe system and preparation method thereof Download PDFInfo
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- CN111102865A CN111102865A CN202010015853.8A CN202010015853A CN111102865A CN 111102865 A CN111102865 A CN 111102865A CN 202010015853 A CN202010015853 A CN 202010015853A CN 111102865 A CN111102865 A CN 111102865A
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- 239000002245 particle Substances 0.000 claims abstract description 129
- 239000002184 metal Substances 0.000 claims abstract description 68
- 229910052751 metal Inorganic materials 0.000 claims abstract description 68
- 239000011148 porous material Substances 0.000 claims abstract description 43
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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
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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
- F28D15/046—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 characterised by the material or the construction of the capillary structure
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- General Engineering & Computer Science (AREA)
- Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
Abstract
The invention discloses a metal-nonmetal composite capillary wick applied to a loop heat pipe system and a preparation method thereof, belonging to the field of loop heat pipes. The capillary core is a double-pore-diameter structure formed by compounding non-metal powder particles and metal powder particles, and comprises the non-metal powder particles, the metal powder particles, small-pore-diameter pores and large-pore-diameter pores; the non-metal powder particles form non-metal powder micelles, the metal powder particles are filled among the non-metal powder micelles, small-aperture pores are formed among the non-metal powder particles, and large-aperture pores are formed among the metal powder particles and the non-metal powder micelles. The invention provides a combination of metal-nonmetal particles, aiming at solving the problems of insufficient suction force or overlarge flow resistance of the traditional single-aperture capillary wick, high heat conductivity of a double-aperture metal capillary wick and easy formation of an integral vapor film in an evaporation area to deteriorate heat transfer in the prior art, and being beneficial to solving the problems of serious heat leakage, deteriorated heat transfer caused by migration of a phase interface to a liquid side and the like of the capillary wick in the operation.
Description
Technical Field
The invention relates to the technical field of loop heat pipes, in particular to a metal-nonmetal composite capillary wick applied to a loop heat pipe system and a preparation method thereof.
Background
The Loop Heat Pipe (LHP) is developed along with the space thermal control technology, is an excellent heat transfer device, has the advantages of high heat flow density, no moving parts, strong temperature uniformity and the like, can transmit long distance and high heat, and has excellent heat transfer performance. The LHP working principle is shown as the attached figure 1: the liquid working medium absorbs heat and evaporates into steam in the capillary core, the steam flows to the condenser 1 through the steam pipeline 4 under the drive of phase change, the steam entering the condenser 1 is condensed to release heat and is condensed into liquid, the condensed liquid working medium enters the compensation cavity in the evaporator 3 through the liquid pipeline 2 under the action of capillary drive to supply liquid working medium for a phase change interface in the capillary core, thereby completing working medium circulation and achieving the purpose of heat dissipation. When the LHP works, the liquid working medium is evaporated in the capillary core inside the LHP to form a gas-liquid phase change interface, so that capillary suction force is provided, and required power is provided for the whole circulating system. From the above, when the LHP is operated, the system can work normally without external force, and the driving force required by the system circulation is provided by capillary suction force.
The capillary wick is the core component of LHP operation. The operational performance of the LHP depends primarily on the heat and mass transfer properties of the capillary wick. The change of the position of the internal phase interface of the evaporator during working, the size of the evaporation area and the formation of the integral vapor film are all important factors influencing the performance of the evaporator. The capillary core needs to provide enough capillary suction force in the working process to overcome the flow resistance generated in the working medium flowing process, so that the capillary core is filled with the liquid working medium in time, enough liquid working medium is provided for the evaporation interface, and the gas-liquid evaporation interface is prevented from migrating to the liquid side, thereby enabling the whole LHP system to normally operate.
The traditional single-aperture capillary wick is single in aperture and large in internal structure limitation as shown in figure 2. If the pore size is too large, although a large evaporation interface can be provided and vapor detachment is facilitated, sufficient capillary suction force cannot be provided for normal operation of the LHP, and meniscus back-up phenomenon can occur in the system during operation; if the pore size is too small, although the capillary suction force is increased, the flow resistance of the liquid working medium in the capillary core is too large, the working medium cannot fill the capillary core in time, and the liquid working medium required by evaporation is provided for the evaporation interface. It can be seen that there is a contradiction in the choice between these two pore sizes. The existing double-aperture capillary wick is shown in figure 3, and although the problems of suction force and flow resistance are solved, under high heat load, the whole effective heat conductivity coefficient of the capillary wick is large, heat leakage is serious, and an evaporation interface is easy to form a whole vapor film to deteriorate heat transfer. Therefore, the research on the high-performance capillary wick has not been stopped all the time.
Through search, the design of the LHP wick has been disclosed in patents, such as chinese patent application No. 2018208685621, application date: 6 months 6 days 2018, the invention and creation name is: a foam metal-fiber composite capillary core applied to a loop heat pipe forms a double-pore-diameter structure in the same pore space, so that the capillary suction force of the capillary core is enhanced, the flow resistance of a liquid working medium is reduced, the flow of the liquid working medium in the capillary core is strengthened, the back leakage heat is reduced to a certain extent, and the LHP performance is improved. Although the structure of the capillary core is partially changed by the scheme, the performance of the LHP is optimized, but the performance of the capillary core has a great improvement space.
Disclosure of Invention
1. Technical problem to be solved by the invention
Aiming at the problems of insufficient suction force or overlarge flow resistance of the traditional single-aperture capillary wick and the problems of serious heat leakage and easy formation of an integral vapor film in an evaporation area to deteriorate and transfer heat of the traditional double-aperture capillary wick in the prior art, the metal-nonmetal composite capillary wick applied to the loop heat pipe system and the preparation method thereof are provided, and the problems of serious heat leakage, deteriorated heat transfer of a phase interface to a liquid side and the like of the capillary wick in the operation are solved.
2. Technical scheme
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
the invention relates to a metal-nonmetal composite capillary core applied to a loop heat pipe system, which is a double-pore-diameter structure formed by compounding nonmetal powder particles and metal powder particles and comprises the nonmetal powder particles, the metal powder particles, small-pore-diameter pores and large-pore-diameter pores; the non-metal powder particles form non-metal powder micelles, the metal powder particles are filled among the non-metal powder micelles, small-aperture pores are formed among the non-metal powder particles, and large-aperture pores are formed among the metal powder particles and the non-metal powder micelles.
Further, the particle diameter of the metal powder particles is 10 to 100. mu.m.
Further, the particle size of the non-metallic powder particles is 1 to 10 μm.
Further, the diameter of the non-metallic powder micelles is larger than the diameter of the metallic powder particles.
Further, the ratio of the total volume of the non-metallic powder particles to the metal powder particles is between 0.2 and 1.
The invention relates to a preparation method of a metal-nonmetal composite capillary wick applied to a loop heat pipe system, which comprises the following steps:
s1, preparing non-metal powder particles and metal powder particles from non-metal and metal materials;
s2, mixing the non-metal powder particles with a solvent to prepare non-metal powder micelle slurry in a flowing state; pouring the non-metal powder micelle slurry into a forming die to prepare a non-metal micelle framework;
s3, mixing the metal powder particles with a solvent to prepare a metal powder slurry in a flowing state;
s4, pouring the metal powder slurry into a forming die filled with the nonmetal powder micelles for mixing, so that the nonmetal powder micelles are filled with the metal powder;
and S5, after filling, taking out the solid capillary core blank from the mold, cleaning to remove additives in the capillary core, and heating and drying to dryness to obtain the product.
Further, the particle diameter of the metal powder particles is 10 to 100. mu.m.
Further, the particle size of the non-metallic powder particles is 1 to 10 μm.
Further, the diameter of the non-metallic powder micelles is larger than the diameter of the metallic powder particles.
Further, the ratio of the total volume of the non-metallic powder particles to the metal powder particles is between 0.2 and 1.
3. Advantageous effects
Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:
(1) the metal-nonmetal composite capillary core applied to the loop heat pipe system is formed by mixing nonmetal powder particles with small particle sizes and metal powder particles with large particle sizes, the capillary core with locally nonuniform heat transfer is prepared, a dispersed two-phase evaporation area is formed, and an integral vapor film is not easy to form, so that the critical heat flow of the capillary core is improved.
(2) According to the metal-nonmetal composite capillary core applied to the loop heat pipe system, in the evaporation process, the nonmetal powder particles stretch the evaporation meniscus of the composite capillary core, so that an evaporation interface is not easy to form an integral vapor film, the integral evaporation heat transfer coefficient is increased, the critical heat flow of evaporation heat transfer is improved, the integral effective heat conductivity coefficient is reduced, the back leakage heat is reduced, and the operation performance of LHP is improved.
(3) According to the metal-nonmetal composite capillary core applied to the loop heat pipe system, local large-aperture pores are formed by metal powder particles, so that expansion of an evaporation interface in the capillary core is facilitated, the area of the evaporation phase-change interface is increased, the surface evaporation rate is improved, and small flow resistance is generated by the flow of a liquid working medium in large apertures, so that the capillary core is filled with the liquid working medium in time. The small-aperture pores formed by the nonmetallic powder particles provide enough capillary suction force for the operation of LHP, provide enough liquid working medium for a gas-liquid evaporation interface, and simultaneously have low thermal conductivity to be unfavorable for evaporation, so that the phase change interface can be maintained on the inner wall surface of the evaporator, liquid supply to the evaporation interface is ensured, the back of an evaporation meniscus of the composite capillary core is prevented, and adverse factors to evaporation are reduced.
(4) The preparation method of the metal-nonmetal composite capillary wick applied to the loop heat pipe system adopts a pouring mode for preparation, is safe and environment-friendly, is simple to prepare, saves resources and reduces cost investment.
Drawings
Figure 1 is a schematic diagram of LHP operation;
FIG. 2 is a schematic view of a local working process of a single pore diameter capillary core under a high thermal load;
FIG. 3 is a schematic view of a partial operation process of a dual-aperture capillary core under a high thermal load;
fig. 4 is a schematic view of the partial operation of the metal-nonmetal composite capillary wick applied to the loop heat pipe system according to the present invention.
The reference numerals in the schematic drawings illustrate:
1. a condenser; 2. a liquid conduit; 3. an evaporator; 4. a steam line;
101. heating the wall surface; 102. single aperture evaporation of the meniscus; 103. single pore size metal particles; 104. single pore capillary core gas phase; 105. single pore capillary core liquid phase; 106. the pore diameter of the single-pore capillary core;
111. a dual-aperture capillary wick meniscus; 112. a dual-pore metal particle; 113. double-aperture capillary core liquid phase; 114. double-aperture capillary core gas phase; 115. the double-aperture capillary core has large aperture; 116. the pore diameter of the double-pore-diameter capillary core is small;
121. non-metallic powder particles; 122. evaporating the meniscus by the composite capillary core; 123. metal powder particles; 124. a small pore size pore; 125. compounding capillary core gas phase; 126. a large pore size pore; 127. and (4) compounding a capillary core liquid phase.
Detailed Description
For a further understanding of the invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The present invention will be further described with reference to the following examples.
Example 1
Fig. 2 shows a local working state diagram of a conventional single-aperture capillary wick under high thermal load in the industry, the capillary wick is prepared by using single-aperture metal particles 103, a single-aperture capillary wick aperture 106 is formed between adjacent single-aperture metal particles 103, a single-aperture evaporation meniscus 102 is formed between a single-aperture capillary wick gas phase 104 and a single-aperture capillary wick liquid phase 105 under a heating wall surface 101, and if the aperture is too large, the single-aperture evaporation meniscus 102 can recede during system operation; if the pore diameter is too small, although the capillary suction force is increased, the flow resistance of the liquid working medium in the capillary core is too large, the working medium cannot fill the capillary core in time, the liquid working medium required by evaporation is provided for an evaporation interface, and the normal use performance is affected.
Fig. 3 shows a local working state diagram of a dual-aperture capillary core under high thermal load in the industry, where the capillary core is a dual-aperture capillary core formed by dual-aperture metal particles 112, and the metal particles form a large and small dual-aperture structure, including a dual-aperture capillary core large aperture 115 and a dual-aperture capillary core small aperture 116; specifically, a dual-aperture capillary core small aperture 116 is formed between two adjacent dual-aperture metal particles 112, and a dual-aperture capillary core large aperture 115 is formed between the cluster-shaped frameworks surrounded by a plurality of dual-aperture metal particles 112. Compared with a single-aperture capillary wick, the capillary wick solves the problems of suction force and flow resistance, but under high heat load, as shown in fig. 3, a double-aperture capillary wick meniscus 111 between a double-aperture capillary wick gas phase 114 and a double-aperture capillary wick liquid phase 113 is easy to form an integral vapor film to deteriorate heat transfer, and normal use performance is affected.
As shown in fig. 4, the metal-nonmetal composite capillary wick applied to the loop heat pipe system of this embodiment has a dual-aperture structure formed by compounding nonmetal powder particles 121 and metal powder particles 123, and includes nonmetal powder particles 121, metal powder particles 123, small-aperture pores 124 and large-aperture pores 126; the non-metal powder particles 121 form non-metal powder micelles, the metal powder particles 123 are filled between the non-metal powder micelles, small-aperture pores 124 are formed between the non-metal powder particles 121, large-aperture pores 126 are formed between the metal powder particles 123, and between the metal powder particles 123 and the non-metal powder micelles. In use, as shown in fig. 4, the composite wick evaporative meniscus 122 between the composite wick vapor phase 125 and the composite wick liquid phase 127 under high thermal load takes on a gourd shape.
In this embodiment, the particle size of the metal powder particles 123 is 10 to 100 μm, the particle size of the non-metal powder particles 121 is 1 to 10 μm, the diameter of the non-metal powder micelles is larger than that of the metal powder particles 123, and the ratio of the total volume of the non-metal powder particles 121 to the total volume of the metal powder particles 123 is 0.2 to 1. The capillary core of the unit of the embodiment is prepared by adopting a pouring mode, and the specific preparation process is as follows:
s1, preparing nonmetal powder particles 121 and metal powder particles 123 from nonmetal and metal materials;
in the embodiment, the metal material is selected from metals with high thermal conductivity, high hardness and high temperature resistance, such as Ti, Cu, Al and the like; the non-metal material is selected from non-metal materials with small heat conductivity coefficient, high temperature resistance and strong plasticity, such as cement, ceramic, polytetrafluoroethylene and other non-metals, the particle size of the prepared metal powder particles 123 is 10-100 mu m, and the particle size of the non-metal powder particles 121 is 1-10 mu m.
S2, mixing the non-metal powder particles 121 with a solvent to prepare a non-metal powder micelle slurry in a flowing state; pouring the non-metal powder micelle slurry into a forming die to prepare a non-metal micelle framework;
specifically, the particle size of the non-metal powder particles 121 is smaller, and the particle size of the metal powder particles 123 is larger, the small-particle non-metal powder particles 121 are firstly made into large-particle non-metal powder micelles, an adaptive solvent such as water is selected according to the properties of a non-metal material, the small-particle non-metal powder particles 121 are mixed with the appropriate solvent, and appropriate additives such as adhesive starch or ammonium bicarbonate are added, so that the formation of a slurry is facilitated, the non-metal powder micelle slurry is prepared, the flowing state is only required, the diameter of the non-metal powder micelle is 800 μm and is larger than that of the metal powder particles 123, and the subsequent filling of the metal powder particle slurry is facilitated; pouring the prepared non-metal powder micelle slurry into a forming die with a set size to prepare a non-metal micelle framework;
s3, mixing the metal powder particles 123 with a solvent to prepare a metal powder slurry in a flowing state;
similarly, according to the properties of the metal powder particles 123, an adaptive solvent such as water is selected, the metal powder particles 123 are mixed with the appropriate solvent, and an additive such as NaCl or ammonium bicarbonate is added to prepare a flowing metal powder particle slurry, wherein the slurry is thinner and is convenient to fill;
s4, pouring the metal powder slurry into a forming die filled with the nonmetal powder micelles for mixing, so that the nonmetal powder micelles are filled with the metal powder;
in this embodiment, the ratio of the total volume of the non-metal powder particles 121 to the total volume of the metal powder particles 123 is 0.2 to 1, the capillary wick evaporation heat transfer performance determines the LHP performance, if the volume occupied by the non-metal is larger than that occupied by the metal, the local evaporation of the capillary wick will be reduced, the evaporation rate of the evaporator will be reduced, and the LHP performance will be reduced, so the total volume of the metal powder particles 123 is larger than the volume of the non-metal powder particles 121; if the total volume of the metal is too large, the total effective thermal conductivity of the composite capillary core is increased, heat leakage is serious, and heat transfer is deteriorated; in the embodiment, the ratio of the total volume of the non-metal powder particles 121 to the total volume of the metal powder particles 123 is controlled to be 0.2-1, so that the quality of the capillary core can be effectively guaranteed.
And S5, finishing filling, taking out the solid capillary core blank from the die, cleaning to remove additives in the capillary core, cleaning by adopting ultrasonic waves, and heating and drying by distillation to obtain the product.
The capillary core of the embodiment is formed by mixing the nonmetal powder particles 121 with small particle size and the metal powder particles 123 with large particle size, so that the capillary core with locally uneven heat transfer is prepared, an evaporation interface forms a dispersed two-phase evaporation area, and an integral vapor film is not easy to form, so that the critical heat flow of the capillary core is improved. Due to the high thermal conductivity of the metal powder particles 123 and the local large-aperture pores 126 formed among the metal powder particles 123, the expansion of an evaporation interface inside the metal powder particles is facilitated, the area of an evaporation phase-change interface is increased, the surface evaporation rate is improved, and the liquid working medium in the large aperture flows to generate smaller flow resistance, so that the capillary core is filled with the liquid working medium in time. The small-aperture pores 124 formed by the non-metal powder particles 121 provide enough capillary suction force for the operation of the LHP, provide enough liquid working medium for a gas-liquid evaporation interface, and simultaneously have low thermal conductivity to be unfavorable for evaporation, so that the phase change interface can be maintained on the inner wall surface of the evaporator, liquid supply to the evaporation interface is ensured, the composite capillary core evaporation meniscus 122 is prevented from backing up, and adverse factors on evaporation are reduced. In addition, in the evaporation process, the nonmetal powder particles 121 stretch the composite capillary wick evaporation meniscus 122, so that an evaporation interface is not easy to form an integral vapor film, the evaporation heat transfer coefficient is increased, the critical heat flow of evaporation heat transfer is improved, the integral effective heat conductivity coefficient is reduced, the back heat leakage is reduced, and the operation performance of LHP is improved.
Compared with the traditional single-pore capillary wick and the existing double-pore-diameter capillary wick, the metal-nonmetal composite capillary wick applied to the loop heat pipe system has the following advantages in LHP working:
A. the phase change evaporation interface is enlarged, the heat and mass transfer effect is better, and the maximum critical heat load is improved:
the composite capillary core of the embodiment has the advantages that the evaporation interface area is increased, the surface evaporation rate is increased, and the evaporation capacity is increased. The contact surface of pores in the capillary core is rough, the capillary core has a certain stretching effect on a liquid working medium, the length of a gas phase, a liquid phase and a solid phase three-phase contact line is prolonged, the evaporation interface environment is optimized, the local thermal conductivity is high, the local temperature of the gas-liquid evaporation interface can be rapidly increased, an integral gas film is not easily formed on the evaporation interface, the evaporation heat transfer and mass transfer effects are enhanced, and the maximum critical heat load is improved.
B. The back leakage heat is greatly reduced, and the overall temperature of LHP operation is reduced:
the compensation chamber temperature determines the operating temperature of the LHP. The composite capillary core of the embodiment has the advantages that due to the fact that the nonmetal with low thermal conductivity exists and occupies a certain proportion, compared with a traditional capillary core, the overall effective thermal conductivity coefficient in the capillary core is greatly reduced, the thermal load of the system is mainly used for evaporation of a phase interface, the thermal load of heat entering the compensation cavity through heat leakage of the capillary core is greatly reduced, back heat leakage is effectively reduced, the temperature of the compensation cavity is low, and therefore the overall operation temperature of the LHP is reduced.
C. The liquid supply effect of the capillary core is good:
compared with the traditional single-pore capillary core and the existing double-pore-diameter capillary core, in the composite capillary core of the embodiment, the metal powder particles 123 surround the nonmetal powder micelles made of the nonmetal powder particles 121 with small particle sizes, the small pores formed among the nonmetal powder particles 121 provide enough suction force for LHP work, and the large pores formed among the metal powder particles 123 and the nonmetal powder micelles effectively reduce the flow resistance of the liquid working medium in the capillary core, so that the liquid supply is enhanced. Meanwhile, the composite capillary core of the embodiment has small effective pore size, increases capillary suction force, provides enough liquid for evaporation of a gas-liquid interface during operation, and prevents the gas-liquid evaporation interface from migrating to the liquid side.
D. Temperature fluctuation is reduced, and the starting performance of the loop heat pipe is accelerated:
in the composite capillary core of the embodiment, the metal powder particles 123 with high thermal conductivity are adopted, and when a heat load is applied to the upper wall surface of the capillary core, because the thermal conductivity coefficient of the metal is high, the local temperature of the upper wall surface of the capillary core can be rapidly increased, local effective evaporation can be generated on the upper wall surface of the capillary core in a short time, and the starting performance of the LHP is accelerated. Because the whole effective heat conductivity coefficient in the capillary core is reduced, the heat leakage of the evaporator is reduced, the temperature of the compensation cavity is low, the fluctuation is small, and gas continuously generated at an evaporation interface is discharged through the channel in time, so that the temperature fluctuation of the evaporator is reduced.
E. The preparation is simple:
the composite capillary core is prepared in a pouring mode, is safe and environment-friendly, is simple to prepare, saves resources and reduces cost investment.
The present invention and its embodiments have been described above schematically, without limitation, and what is shown in the drawings is only one of the embodiments of the present invention, and the actual structure is not limited thereto. Therefore, if the person skilled in the art receives the teaching, without departing from the spirit of the invention, the person skilled in the art shall not inventively design the similar structural modes and embodiments to the technical solution, but shall fall within the scope of the invention.
Claims (10)
1. A metal-nonmetal composite capillary core applied to a loop heat pipe system is characterized in that: the capillary core is a double-aperture structure formed by compounding non-metal powder particles (121) and metal powder particles (123), and comprises the non-metal powder particles (121), the metal powder particles (123), small-aperture pores (124) and large-aperture pores (126); the non-metal powder particles (121) form non-metal powder micelles, the metal powder particles (123) are filled between the non-metal powder micelles, small-aperture pores (124) are formed between the non-metal powder particles (121), and large-aperture pores (126) are formed between the metal powder particles (123) and the non-metal powder micelles.
2. The metal-nonmetal composite capillary wick applied to the loop heat pipe system according to claim 1, wherein: the particle diameter of the metal powder particles (123) is 10 to 100 μm.
3. The metal-nonmetal composite capillary wick applied to the loop heat pipe system according to claim 1, wherein: the particle diameter of the non-metal powder particles (121) is 1-10 μm.
4. The metal-nonmetal composite capillary wick applied to the loop heat pipe system according to claim 1, wherein: the diameter of the non-metallic powder micelles is larger than the diameter of the metal powder particles (123).
5. The metal-nonmetal composite capillary wick applied to the loop heat pipe system according to any one of claims 1-4, wherein: the ratio of the total volume of the non-metallic powder particles (121) to the total volume of the metallic powder particles (123) is between 0.2 and 1.
6. A preparation method of a metal-nonmetal composite capillary wick applied to a loop heat pipe system is characterized by comprising the following steps: the method comprises the following steps:
s1, preparing non-metal powder particles (121) and metal powder particles (123) from non-metal and metal materials;
s2, mixing the non-metal powder particles (121) with a solvent to prepare non-metal powder micelle slurry in a flowing state; pouring the non-metal powder micelle slurry into a forming die to prepare a non-metal micelle framework;
s3, mixing the metal powder particles (123) with a solvent to prepare a metal powder slurry in a flowing state;
s4, pouring the metal powder slurry into a forming die filled with the nonmetal powder micelles for mixing, so that the nonmetal powder micelles are filled with the metal powder;
and S5, after filling, taking out the solid capillary core blank from the mold, cleaning to remove additives in the capillary core, and heating and drying to dryness to obtain the product.
7. The method for preparing the metal-nonmetal composite capillary wick applied to the loop heat pipe system according to claim 6, wherein: the particle diameter of the metal powder particles (123) is 10 to 100 μm.
8. The method for preparing the metal-nonmetal composite capillary wick applied to the loop heat pipe system according to claim 6, wherein: the particle diameter of the non-metal powder particles (121) is 1-10 μm.
9. The method for preparing the metal-nonmetal composite capillary wick applied to the loop heat pipe system according to claim 6, wherein: the diameter of the non-metallic powder micelles is larger than the diameter of the metal powder particles (123).
10. The method for preparing the metal-nonmetal composite capillary wick applied to the loop heat pipe system according to any one of claims 6-9, wherein: the ratio of the total volume of the non-metallic powder particles (121) to the total volume of the metallic powder particles (123) is between 0.2 and 1.
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| CN112414189A (en) * | 2020-11-02 | 2021-02-26 | 华中科技大学 | Flat evaporator suitable for cast capillary core |
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