A loop heat pipe evaporator using aluminum powder sintering for aerospace field

Abstract

The application discloses a loop heat pipe evaporator adopting aluminum powder sintering in the field of spaceflight, which comprises an evaporator tube shell, a capillary core, a liquid trunk, a gas channel and a liquid reservoir; the evaporator tube shell is made of 6 series aluminum alloy, the capillary core is made of aluminum powder sintering, the capillary core is directly sintered in the evaporator tube shell, and the capillary core is a porous medium; the gas channel and the liquid trunk are made through a mold without machining, the gas channel is located at the joint of the evaporator tube shell and the capillary core, and the liquid trunk is located at the center of the capillary core. The application has simple structure, simple technological process, adopts aluminum as the evaporator material, greatly reduces the weight of the heat pipe, is compatible with ammonia, can adopt ammonia as the working medium, and strengthens the heat transfer capacity of the heat pipe.

Description

Technical Field

[0001] This invention relates to the field of radiator technology, and particularly to a loop heat pipe evaporator using aluminum powder sintering for use in the aerospace industry. Background Technology

[0002] Space missions have stringent requirements regarding payload weight; the greater the weight, the higher the launch cost. As auxiliary equipment, heat dissipation devices face even stricter weight requirements. Loop heat pipes offer high heat transfer capacity, flexible connections, vibration isolation, long-distance heat transfer, and the ability to operate under microgravity or even antigravity conditions, making them widely used in the aerospace field both domestically and internationally.

[0003] The core issues that need to be addressed for the application of loop heat pipes in the aerospace field:

[0004] (1) Reduce the overall weight;

[0005] (2) Simplify the process flow and reduce costs.

[0006] Traditional loop heat pipes are mostly made of stainless steel, nickel, or copper. These three materials have high density and high sintering temperatures, and the raw material costs of copper and nickel remain high. Secondly, traditional loop heat pipes use an interference fit to insert the capillary wick into the evaporator shell, which can easily damage the capillary wick during the process. The existing main technical solutions for processing loop heat pipe evaporators are as follows:

[0007] First, the evaporator shell and the capillary wick body are machined separately. After the capillary wick body is sintered, it needs to undergo machining, cleaning, drying, and measurement processes. If the dimensional accuracy of the capillary wick body matches that of the evaporator shell, it is then inserted into the evaporator shell using either hot or cold assembly. This design process is complex, requires precision machining of the capillary wick body, and is costly and time-consuming. Therefore, there is an urgent need to design a solution with a simple structure and low manufacturing difficulty to address the problems of complex processes and heavy weight associated with traditional loop heat pipes. Summary of the Invention

[0008] To solve the above-mentioned technical problems, this invention discloses a loop heat pipe evaporator for aerospace applications using aluminum powder sintering, comprising an evaporator shell 1-1, a capillary 1-2, a liquid main channel 1-3, a gas channel 1-4, and a liquid reservoir 1-5. The capillary 1-2 is directly sintered together with the evaporator shell 1-1, without the need for assembly.

[0009] The gas channel 1-4 and the liquid channel 1-3 are both formed by molds during the sintering process, without the need for machining; the liquid channel 1-3 is located at the center of the capillary 1-2 and does not penetrate the capillary 1-2, and the gas channel 1-4 is located between the tube shell and the capillary 1-2 and does not penetrate the capillary 1-2.

[0010] The capillary cores 1-2 are made of aluminum and are manufactured by loose sintering of aluminum powder.

[0011] The evaporator shell 1-1 is made of 6-series aluminum alloy;

[0012] This invention overcomes the shortcomings of the prior art and provides a loop heat pipe evaporator using aluminum powder sintering for the aerospace field. It can reduce the weight of the loop heat pipe and has more compatible working fluids. Moreover, it has a simple structure, low manufacturing difficulty, and significantly improves the applicability of the loop heat pipe. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only one embodiment of the present invention.

[0014] Figure 1 A cross-sectional view of a loop heat pipe evaporator using aluminum powder sintering for use in the aerospace field;

[0015] Figure 2 This is a schematic diagram of mold number one;

[0016] Figure 3 This is a schematic diagram of mold number two;

[0017] In the above figures, the figure numbers indicate the following:

[0018] 1-1. Evaporator shell and tubes;

[0019] 1-2 capillary wicks;

[0020] 1-3. Liquid main channel;

[0021] 1-4. Gas channels;

[0022] 1-5. Liquid reservoir;

[0023] 2-1, Module A1;

[0024] 2-2, Module A2;

[0025] 3-1, Module B1;

[0026] 3-2, Module B2; Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1

[0029] In one specific embodiment, such as Figure 1 As shown, a loop heat pipe evaporator using aluminum powder sintering for aerospace applications includes an evaporator shell 1-1, a capillary wick 1-2, a liquid main channel 1-3, a gas channel 1-4, and a liquid reservoir 1-5. The capillary wick 1-2 is sintered inside the evaporator shell 1-1.

[0030] The gas channels 1-4 are formed on the outer surface of the capillary core 1-2;

[0031] The liquid channel 1-3 is located at the center of the capillary wick 1-2, the depth of the liquid channel 1-3 is less than the length of the capillary wick 1-2, and the liquid channel 1-3 is located on one side of the reservoir 1-5.

[0032] The liquid reservoir 1-5, liquid main 1-3 and gas channel 1-4 are manufactured using molds during the sintering process of capillary core 1-2.

[0033] The mold includes mold number one and mold number two, such as Figure 2 and Figure 3 As shown,

[0034] The capillary cores 1-2 are porous media, made by sintering aluminum powder.

[0035] This embodiment adopts a technical solution of sintering aluminum powder together with the tube shell. First, the No. 1 mold, the liquid storage tank 1-5 mold and the evaporator tube shell 1-1 are assembled. Finally, the aluminum powder and sintering aid are mixed evenly and loaded into the tube shell. The furnace sintering gas channel 1-4 and liquid main channel 1-3 are prepared by the No. 1 mold and the No. 2 mold, respectively. Compared with the existing technology, the assembly of the capillary core 1-2 and the machining of the gas channel 1-4 and liquid main channel 1-3 are eliminated. The structure is simple, the process is less difficult, and the weight is small.

[0036] In this embodiment, the capillary wick 1-2 is a sintered porous medium composed of a solid skeleton and the pores between the solid skeleton. The liquid working fluid in the liquid reservoir 1-5 and the liquid main channel 1-3 wets the capillary wick 1-2 under the action of capillary force. An external heat source enters the evaporator shell 1-1 to heat the liquid on the surface of the gas channel 1-4, causing it to evaporate. The gas formed by evaporation flows out of the evaporator through the gas channel (1-4).

Claims

1. A loop heat pipe evaporator using aluminum powder sintering for aerospace applications, comprising an evaporator shell (1-1), a capillary wick (1-2), a liquid main channel (1-3), a gas channel (1-4), and a liquid reservoir (1-5); characterized in that: The evaporator shell (1-1) is made of 6-series aluminum alloy; The capillary wick (1-2) is directly sintered in the evaporator shell (1-1). The evaporator shell (1-1) includes the capillary wick (1-2) and extends outwards, with the extended portion serving as a liquid reservoir (1-5). The capillary wick (1-2) is a porous medium and is prepared by loose sintering of aluminum powder. The liquid channel (1-3) is located at the center of the capillary wick (1-2), and the gas channel (1-4) is located on the outer surface of the capillary wick (1-2). Neither of them penetrates the entire capillary wick (1-2). The gas channel (1-4) opens in the opposite direction to the liquid channel (1-3). The depth of the liquid channel (1-3) is less than the length of the capillary wick (1-2), and the liquid channel (1-3) is opened on one side of the reservoir (1-5); The liquid reservoir (1-5), gas channel (1-4), and liquid main channel (1-3) are formed by using molds during the sintering process of the capillary core (1-2); the molds include mold No. 1 and mold No. 2; During processing, the No. 1 mold, the liquid storage mold and the evaporator shell (1-1) are first assembled. Then, aluminum powder and sintering aid are mixed evenly and put into the evaporator shell (1-1) for sintering in the furnace. The No. 1 mold forms the gas channel (1-4) and the No. 2 mold forms the liquid channel (1-3). During the operation of the equipment, the liquid working medium in the liquid reservoir (1-5) and the liquid main channel (1-3) wets the capillary core (1-2) under the action of capillary force. An external heat source enters the evaporator shell (1-1) and heats the liquid on the surface of the gas channel (1-4) to make it evaporate. The gas formed by evaporation flows out of the evaporator through the gas channel (1-4).

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