Two-phase fluid loop system for spacecraft heat rejection

Abstract

The present application relates to the field of spacecraft thermal control technology, and provides a two-phase fluid loop system for spacecraft heat dissipation, comprising an evaporation unit, a pump-driven two-phase fluid loop and a heat pump loop, the evaporation unit is provided with a liquid accumulator for storing heat transfer working medium, a micro-channel cold plate, the micro-channel cold plate comprises a micro-channel cold plate inlet, a micro-channel cold plate liquid phase outlet and a micro-channel cold plate vapor phase outlet; the pump-driven two-phase fluid loop is provided with a mechanical pump and a first radiator, the outlet of the first radiator is connected with the liquid accumulator liquid phase fluid inlet of the liquid accumulator; the heat pump loop is provided with a compressor and a second radiator, and the second radiator is connected with the liquid accumulator through a throttle valve. The present application can effectively reduce the weight of the system and the launch cost, and the micro-channel cold plate has the function of vapor-liquid separation in a closed system, which reduces the internal flow instability, improves the heat exchange capacity and the critical heat flux density, and solves the problems of mechanical pump cavitation and compressor liquid knock.

Description

Technical Field

[0001] This invention relates to the field of spacecraft thermal control technology, specifically to a two-phase fluid loop system for spacecraft heat dissipation, and more particularly to a two-phase fluid loop system for high-power, high-heat-fluidity heat dissipation from multiple heat sources in spacecraft. Background Technology

[0002] With the development of manned spaceflight, high-power communication satellites, space nuclear power, and space power stations, the power level of spacecraft is showing a significant increasing trend. For example, the total power of my country's space station has reached nearly 30kW, while communication satellites have exceeded 10kW, with heat dissipation about 10 times that of ordinary satellites. Future nuclear-powered spacecraft will reach the MW level, and space power stations will reach the GW level, with heat dissipation nearly a million times that of existing ordinary satellites. System power is one of the main factors affecting thermal design, and high-power heat collection, transmission, and dissipation technologies are becoming an important future development direction.

[0003] As payloads and devices evolve towards miniaturization, integration, and modularity, high heat flux density is another important trend in the development of future spacecraft. For example, laser diodes, high-power sensor chips, and GHz-level LSI / VLSI electronic chips used in space communication systems can achieve heat flux densities of hundreds of W / cm². 2 The performance and reliability of these devices are directly related to their operating temperature. They not only require low operating temperatures but also excellent temperature uniformity. Traditional spacecraft thermal control technologies are no longer applicable. The heat dissipation and thermal management of high heat flux density in space has become one of the bottlenecks restricting the future development of spacecraft.

[0004] Mechanically pumped two-phase fluid loops with integrated high aspect ratio microchannel cold plates are one of the important technical approaches to solving the problem of concentrated heat dissipation from multiple high-power, high-heat-fluidity heat sources in spacecraft. However, high-power radiators based on mechanically pumped two-phase fluid loops are too heavy, significantly increasing launch costs. Furthermore, bottlenecks such as the instability of two-phase flow inside the microchannel cold plate and the early critical heat flux density significantly restrict the large-scale application of mechanically pumped two-phase fluid loop technology in space. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the purpose of this invention is to provide a two-phase fluid loop system for heat dissipation in spacecraft.

[0006] A two-phase fluid loop system for spacecraft heat dissipation, provided by the present invention, comprises:

[0007] An evaporation unit is equipped with a liquid reservoir for storing the heat transfer medium and a microchannel cold plate connected to the outlet of the liquid reservoir. The microchannel cold plate includes a microchannel cold plate inlet, a microchannel cold plate liquid phase outlet, and a microchannel cold plate vapor phase outlet.

[0008] The pump-driven two-phase fluid circuit is equipped with a mechanical pump whose inlet is connected to the liquid phase outlet of the microchannel cold plate and a first radiator whose inlet is connected to the outlet of the mechanical pump. The outlet of the first radiator is connected to the liquid phase fluid inlet of the liquid reservoir.

[0009] The heat pump circuit is equipped with a compressor whose inlet is connected to the vapor phase outlet of the microchannel cold plate and a second radiator whose inlet is connected to the compressor outlet. The outlet of the second radiator is connected to the vapor-liquid two-phase fluid inlet of the liquid receiver through a throttle valve.

[0010] Preferably, the reservoir is equipped with a heater, which enables the adjustment of the saturation pressure of the heat transfer medium in the reservoir.

[0011] Preferably, the microchannel cold plate further includes a first microchannel group, a first vapor-liquid separation chamber, a second microchannel group, a second vapor-liquid separation chamber, a third microchannel group, and a third vapor-liquid separation chamber connected in sequence. The inlet of the microchannel cold plate is located on the first microchannel group. The third vapor-liquid separation chamber is connected to the mechanical pump through the liquid phase outlet of the microchannel cold plate. The first vapor-liquid separation chamber, the second vapor-liquid separation chamber, and the third vapor-liquid separation chamber are all connected to the compressor through the vapor phase outlet of the microchannel cold plate.

[0012] Preferably, the first vapor-liquid separation chamber includes a first vapor-liquid collection chamber, a first nanoporous membrane, a first microporous plate, a first liquid phase separation microchannel group, a first vapor phase separation chamber, a first vapor phase separation chamber outlet, and a first vapor phase transport channel. The first vapor-liquid collection chamber is adjacent to and interconnected with the first microchannel group.

[0013] When the heat transfer medium in the first microchannel group absorbs heat and enters the first vapor-liquid collection chamber, the vapor working medium after absorbing heat and boiling sequentially passes through the first nanoporous membrane and the first microporous plate into the first vapor phase separation chamber, and then through the outlet of the first vapor phase separation chamber and the first vapor phase transport channel into the vapor phase outlet of the microchannel cold plate. The liquid working medium in the first vapor-liquid collection chamber enters the second microchannel group through the first liquid phase separation microchannel group. The first vapor phase separation chamber and the second microchannel group are not connected.

[0014] Preferably, the second vapor-liquid separation chamber and the third vapor-liquid separation chamber have the same structure as the first vapor-liquid separation chamber.

[0015] Preferably, the first microchannel group, the second microchannel group, and the third microchannel group each include multiple parallel microchannels, and the cross-sectional area of ​​the microchannels gradually increases along the fluid flow direction.

[0016] Preferably, the equivalent diameter of multiple parallel microchannels is no greater than 1 mm.

[0017] Preferably, the heater is a polyimide film heater;

[0018] The microchannel cold plate is made of aluminum alloy or copper.

[0019] Preferably, the heater is attached to the outer surface of the reservoir using GD414C silicone rubber.

[0020] Preferably, the heat transfer medium is liquid ammonia or R134a.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] This invention employs a phase change heat transfer technology based on a mechanically pumped two-phase fluid loop coupled with a heat pump loop and a co-evaporator using a microchannel cold plate with a large aspect ratio. This technology can effectively reduce the weight of high-power, high-heat-fluidity heat dissipation systems for spacecraft under multi-heat-source conditions, thereby reducing launch costs. Furthermore, the microchannel cold plate has a vapor-liquid separation function within a closed system, which reduces internal flow instability, improves heat exchange capacity and critical heat flux density, and solves the problems of mechanical pump cavitation and compressor liquid slugging. Attached Figure Description

[0023] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0024] Figure 1 This is a schematic diagram of the process structure of the present invention;

[0025] Figure 2 This is a schematic diagram of the structure of the high aspect ratio microchannel cold plate in this invention;

[0026] Figure 3 This is a schematic diagram of the structure of the first vapor-liquid separation chamber of the microchannel cold plate with a large aspect ratio in this invention.

[0027] The diagram shows:

[0028] Mechanical pump 1

[0029] First radiator 2

[0030] Liquid reservoir 3

[0031] Vapor-liquid two-phase fluid inlet 31

[0032] Liquid phase fluid inlet 32 ​​of the reservoir

[0033] Heater 4

[0034] Microchannel cold plate 5

[0035] Microchannel cold plate inlet 51

[0036] First microchannel group 52

[0037] First vapor-liquid separation chamber 53

[0038] First vapor-liquid collection chamber 531

[0039] First nanoporous membrane 532

[0040] First micron porous plate 533

[0041] First Liquid Phase Separation Microchannel Group 534

[0042] First vapor phase separation chamber 535

[0043] 536 Outlet of the first vapor phase separation chamber

[0044] First Automotive Phase Conveyor Channel 537

[0045] Second microchannel group 54

[0046] Second vapor-liquid separation chamber 55

[0047] Second vapor phase separation chamber outlet 556

[0048] Third microchannel group 56

[0049] Third vapor-liquid separation chamber 57

[0050] The outlet of the third vapor phase separation chamber is 576.

[0051] Microchannel cold plate liquid phase outlet 58

[0052] Microchannel cold plate vapor phase outlet 59

[0053] Compressor 6

[0054] Second radiator 7 Detailed Implementation

[0055] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0056] Example 1:

[0057] This invention provides a two-phase fluid loop system for spacecraft heat dissipation, such as... Figure 1As shown, the system includes an evaporation unit, a pump-driven two-phase fluid circuit, and a heat pump circuit. The evaporation unit is equipped with a liquid receiver 3 for storing the heat transfer medium and a microchannel cold plate 5 connected to the outlet of the liquid receiver 3. The heat transfer medium is liquid ammonia or R134a. The microchannel cold plate 5 includes a microchannel cold plate inlet 51, a microchannel cold plate liquid phase outlet 58, and a microchannel cold plate vapor phase outlet 59. The pump-driven two-phase fluid circuit is equipped with a mechanical pump 1 whose inlet is connected to the microchannel cold plate liquid phase outlet 58 and a first radiator 2 whose inlet is connected to the outlet of the mechanical pump 1. The liquid receiver 3 has a vapor-liquid two-phase fluid inlet 31 and a liquid receiver liquid phase fluid inlet 32. The outlet of the first radiator 2 is connected to the liquid receiver liquid phase fluid inlet 32. The heat pump circuit is equipped with a compressor 6 whose inlet is connected to the microchannel cold plate vapor phase outlet 59 and a second radiator 7 whose inlet is connected to the outlet of the compressor 6. The outlet of the second radiator 7 is connected to the vapor-liquid two-phase fluid inlet 31 through a throttle valve 8.

[0058] A heater 4 is installed on the liquid reservoir 3, which can adjust the saturation pressure of the heat transfer medium in the liquid reservoir 3, thereby adjusting the operating temperature of the entire microchannel cold plate 5 and improving the heat exchange effect. The heater 4 is preferably located outside the liquid reservoir 3.

[0059] like Figure 2 As shown, the microchannel cold plate 5 includes a first microchannel group 52, a first vapor-liquid separation chamber 53, a second microchannel group 54, a second vapor-liquid separation chamber 55, a third microchannel group 56, and a third vapor-liquid separation chamber 57 connected in sequence. The microchannel cold plate inlet 51 is located on the first microchannel group 52. The third vapor-liquid separation chamber 57 is connected to the mechanical pump 1 through the microchannel cold plate liquid phase outlet 58. The first vapor-liquid separation chamber 53, the second vapor-liquid separation chamber 55, and the third vapor-liquid separation chamber 57 are all connected to the compressor 6 through the microchannel cold plate vapor phase outlet 59.

[0060] like Figure 3 As shown, the first vapor-liquid separation chamber 53 includes a first vapor-liquid collecting chamber 531, a first nanoporous membrane 532, a first microporous plate 533, a first liquid phase separation microchannel group 534, a first vapor phase separation chamber 535, a first vapor phase separation chamber outlet 536, and a first vapor phase transport channel 537. The first vapor-liquid collecting chamber 531 is adjacent to the end of the first microchannel group 52 and is interconnected with it. The first nanoporous membrane 532 and the first microporous plate 533 are connected between the first vapor-liquid collecting chamber 531 and the first vapor phase separation chamber 535. The first nanoporous membrane 532 is adjacent to the first vapor-liquid collecting chamber 531, and the first microporous plate 533 is adjacent to the first vapor phase separation chamber 535. The first vapor phase separation chamber outlet 536 and the microchannel cold plate vapor phase outlet 59 are connected through the first vapor phase transport channel 537.

[0061] Furthermore, after the heat transfer medium in the first microchannel group 52 absorbs heat and enters the first vapor-liquid collection chamber 531, the vapor phase working medium after absorbing heat and boiling sequentially passes through the first nanoporous membrane 532, the first microporous plate 533, the first vapor phase separation chamber 535, the first vapor phase separation chamber outlet 536, and the first vapor phase transport channel 537 into the vapor phase outlet 59 of the microchannel cold plate. The liquid phase working medium in the first vapor-liquid collection chamber 531 enters the second microchannel group 54 through the first liquid phase separation microchannel group 534, realizing the separation of the gas phase and liquid phase after the heat transfer medium absorbs heat. The first vapor phase separation chamber 535 is not connected to the second microchannel group 54.

[0062] The second vapor-liquid separation chamber 55 and the third vapor-liquid separation chamber 57 have the same structure as the first vapor-liquid separation chamber 53, and their working principles are also the same as those of the first vapor-liquid separation chamber 53.

[0063] Specifically, the supercooled liquid flowing out of the first radiator 2 can lower the temperature of the reservoir 3, thereby reducing its saturation pressure. The structures of the first radiator 2 and the second radiator 7 both adopt existing technology and will not be described in detail here.

[0064] Example 2:

[0065] This embodiment is a preferred example of Embodiment 1.

[0066] In this embodiment, the microchannel cold plate 5 is made of aluminum alloy or copper. The first microchannel group 52, the second microchannel group 54, and the third microchannel group 56 each include multiple parallel microchannels. The cross-sectional area of ​​the microchannels gradually increases along the fluid flow direction, reducing the instability of the fluid flow. The equivalent diameter of the multiple parallel microchannels is no greater than 1 mm, for example, the equivalent diameter of the parallel microchannels is 0.5 mm. The cross-section of the parallel microchannels is rectangular, and the four sides gradually increase along the flow direction. In this embodiment, the inlet cross-section of the parallel microchannels is preferably a 0.5 mm × 0.5 mm square, and the outlet cross-section is a 1 mm × 1 mm square.

[0067] In this embodiment, heater 4 is a polyimide film heater, and heater 4 is attached to the outer surface of reservoir 3 with GD414C silicone rubber.

[0068] In this embodiment, the first nanoporous membrane 532 is a graphene porous nanomembrane or an alumina porous nanomembrane, and the first micron porous plate 533 is made of aluminum alloy or copper.

[0069] In this embodiment, the first liquid phase separation microchannel group 534 includes several parallel microchannels. The parallel microchannels are circular, and the equivalent diameter of the parallel microchannels is no greater than 1 mm and the equivalent diameter of the parallel microchannels is 0.5 mm.

[0070] In this embodiment, the second vapor-liquid separation chamber 55 and the third vapor-liquid separation chamber 57 have the same structure as the first vapor-liquid separation chamber 53. For example, the second vapor-liquid separation chamber 55 has a second vapor phase separation chamber outlet 556, and the third vapor phase separation chamber 57 has a third vapor phase separation chamber outlet 576. Both the second vapor phase separation chamber outlet 556 and the third vapor phase separation chamber outlet 576 have the same structure and function as the first vapor phase separation chamber outlet 536. Specifically, the second vapor phase separation chamber outlet 556 is connected to the microchannel cold plate vapor phase outlet 59 through a second vapor phase transport channel. The third vapor phase separation chamber outlet 576 is connected to the microchannel cold plate vapor phase outlet 59 through a third vapor phase transport channel. Other structures in the second vapor-liquid separation chamber 55 and the third vapor-liquid separation chamber 57 are also the same as those in the first vapor-liquid separation chamber 53, and will not be described again here.

[0071] The working principle of this invention is as follows:

[0072] like Figure 1 As shown, multiple high-power, high-heat-fluid-density heat sources are arranged on the surface of the microchannel cold plate 5. After the fluid inside the microchannel cold plate 5 absorbs heat, it undergoes flow and boiling. Then, the gaseous working fluid passes through the nanoporous membrane and the microporous plate and enters the compressor 6, becoming high-temperature and high-pressure steam. It condenses into high-temperature and high-pressure liquid in the second radiator 7, and becomes a low-temperature and low-pressure fluid with a small amount of gas through the throttling valve 8, entering the liquid reservoir 3. The liquid working fluid inside the microchannel cold plate 5 flows into the mechanical pump 1 through the liquid phase separation microchannel group, and then flows into the liquid reservoir 3 after being subcooled by the first radiator 2.

[0073] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0074] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A two-phase fluid loop system for heat removal from a spacecraft, characterized by, include: The evaporation unit is equipped with a liquid reservoir (3) for storing heat transfer medium and a microchannel cold plate (5) connected to the outlet of the liquid reservoir (3). The microchannel cold plate (5) includes a microchannel cold plate inlet (51), a microchannel cold plate liquid phase outlet (58), and a microchannel cold plate vapor phase outlet (59). The pump-driven two-phase fluid circuit is equipped with a mechanical pump (1) whose inlet is connected to the liquid phase outlet (58) of the microchannel cold plate and a first radiator (2) whose inlet is connected to the outlet of the mechanical pump (1). The outlet of the first radiator (2) is connected to the liquid phase fluid inlet (32) of the reservoir (3). The heat pump circuit is equipped with a compressor (6) whose inlet is connected to the vapor phase outlet (59) of the microchannel cold plate and a second radiator (7) whose inlet is connected to the outlet of the compressor (6). The outlet of the second radiator (7) is connected to the vapor-liquid two-phase fluid inlet (31) of the liquid reservoir (3) through a throttle valve (8). The microchannel cold plate (5) further includes a first microchannel group (52), a first vapor-liquid separation chamber (53), a second microchannel group (54), a second vapor-liquid separation chamber (55), a third microchannel group (56), and a third vapor-liquid separation chamber (57) connected in sequence. The inlet (51) of the microchannel cold plate is located on the first microchannel group (52). The third vapor-liquid separation chamber (57) is connected to the mechanical pump (1) through the liquid phase outlet (58) of the microchannel cold plate. The first vapor-liquid separation chamber (53), the second vapor-liquid separation chamber (55), and the third vapor-liquid separation chamber (57) are all connected to the compressor (6) through the vapor phase outlet (59) of the microchannel cold plate. The first vapor-liquid separation chamber (53) includes a first vapor-liquid collection chamber (531), a first nanoporous membrane (532), a first microporous plate (533), a first liquid phase separation microchannel group (534), a first vapor phase separation chamber (535), a first vapor phase separation chamber outlet (536), and a first vapor phase transport channel (537). The first vapor-liquid collection chamber (531) is adjacent to and interconnected with the first microchannel group (52). When the heat transfer medium in the first microchannel group (52) absorbs heat and enters the first vapor-liquid collection chamber (531), and the vapor working medium after absorbing heat and boiling sequentially passes through the first nanoporous membrane (532), the first microporous plate (533) and enters the first vapor phase separation chamber (535), and then enters the vapor phase outlet (59) of the microchannel cold plate through the outlet (536) of the first vapor phase separation chamber and the first vapor phase transport channel (537). The liquid working medium in the first vapor-liquid collection chamber (531) enters the second microchannel group (54) through the first liquid phase separation microchannel group (534). The first vapor phase separation chamber (535) and the second microchannel group (54) are not connected.

2. The two-phase fluid loop system for heat removal from a spacecraft of claim 1, wherein, The reservoir (3) is equipped with a heater (4) which enables the adjustment of the saturation pressure of the heat transfer medium in the reservoir (3).

3. The two-phase fluid loop system for heat removal from a spacecraft of claim 1 wherein, The second vapor-liquid separation chamber (55) and the third vapor-liquid separation chamber (57) have the same structure as the first vapor-liquid separation chamber (53).

4. The two-phase fluid loop system for spacecraft heat dissipation according to claim 1, characterized in that, The first microchannel group (52), the second microchannel group (54), and the third microchannel group (56) each include multiple parallel microchannels, and the cross-sectional area of ​​the microchannels gradually increases along the fluid flow direction.

5. The two-phase fluid loop system for spacecraft heat dissipation according to claim 4, characterized in that, The equivalent diameter of multiple parallel microchannels is no greater than 1 mm.

6. The two-phase fluid loop system for spacecraft heat dissipation according to claim 2, characterized in that, The heater (4) is a polyimide film heater; The microchannel cold plate (5) is made of aluminum alloy or copper.

7. The two-phase fluid loop system for spacecraft heat dissipation according to claim 2, characterized in that, The heater (4) is attached to the outer surface of the reservoir (3) using GD414C silicone rubber.

8. The two-phase fluid loop system for spacecraft heat dissipation according to claim 1, characterized in that, The heat transfer medium is liquid ammonia or R134a.

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