CN117602109A - Spacecraft assembly and spacecraft - Google Patents

Abstract

The invention relates to the field of aerospace application, and discloses a spacecraft assembly and a spacecraft. A spacecraft assembly comprising: a heat collector and a functional module mounted on the heat collector; the functional module comprises: the vacuum isothermal cavity substrate and the heating device are provided with a phase change heat exchange medium inside; the vacuum isothermal cavity substrate is provided with a first surface for mounting a heating device; a thermally conductive filler is filled between the first surface and the heat generating device. According to the spacecraft assembly, the vacuum isothermal cavity substrate is used for replacing a traditional metal mounting frame to mount the heating device, the phase-change heat exchange medium is arranged in the vacuum isothermal cavity substrate, phase change occurs through the phase-change heat exchange medium, such as heat absorption and gasification of a liquid heat exchange medium, heat transfer is carried out, the heat transfer coefficient is large, the heat transfer quantity is large, the vacuum isothermal cavity substrate collects heat of the functional module and conducts the heat to the heat collector for heat dissipation, the use requirement of higher power can be met, and the heat conduction assembly is not required to be additionally added.

Description

Spacecraft assembly and spacecraft

Technical Field

The invention relates to the technical field of aerospace application, in particular to a spacecraft assembly and a spacecraft.

Background

The main working task of the satellite and other spacecraft thermal control systems is to ensure that the satellite-mounted component mounting surface and the modules inside the components can maintain the required temperature range under the conditions of transmitting, storing and working by using a thermal control means. Due to the special working conditions of spacecrafts such as satellites, the external thermal environment is extremely complex, the thermal environment is influenced by solar irradiation, earth reflection and earth infrared radiation periodically, the radiation background temperature is only 4K because the thermal environment is in the cold and black background of space, and in addition, due to the limitation of vacuum conditions, the final heat dissipation channel for the internal components of the spacecrafts can dissipate heat to the space environment only through radiation.

With the continuous development of spacecraft technologies such as satellites, the continuous development of functional performance is accompanied by the continuous increase of power consumption, heat consumption and power density, which provides new challenges for the heat dissipation technology of spacecraft components, and in some cases, the heat control technology used by the traditional spacecraft cannot meet the use requirements, or valuable on-board resources such as weight, power consumption and the like are consumed to meet the use requirements.

Disclosure of Invention

The invention discloses a spacecraft assembly and a spacecraft, which are used for meeting the heat dissipation requirement of higher power.

In order to achieve the above purpose, the present invention provides the following technical solutions:

in a first aspect, the present invention provides a spacecraft assembly comprising: a heat collector and a functional module mounted on the heat collector;

the functional module includes: the vacuum isothermal cavity substrate and the heating device are arranged in the vacuum isothermal cavity substrate, and a phase change heat exchange medium is arranged in the vacuum isothermal cavity substrate; the vacuum isothermal cavity substrate is provided with a first surface for mounting the heating device; and a heat conducting filler is filled between the first surface and the heating device.

Above-mentioned spacecraft subassembly adopts vacuum isothermal cavity base plate to replace traditional metal installation frame installation heating device, and vacuum isothermal cavity base plate is inside to have the phase transition heat transfer medium, takes place the phase transition through the phase transition heat transfer medium and carries out heat transfer, and heat transfer quantity is big, and vacuum isothermal cavity base plate collects the heat of function module and carries out the heat dissipation with heat conduction to the heat collector, can satisfy the operation requirement of more power, does not need additionally to increase heat conduction component.

In some embodiments, a heat dissipating bump facing the heat generating device is disposed on the first surface, and the heat conductive filler is filled between the heat dissipating bump and the heat generating device; and the gap between the heating device and the heat dissipation protrusion is smaller than the thickness of the heat conduction filler.

In some embodiments, the orthographic projection of the thermally conductive filler on the first surface covers the orthographic projection of the heat generating device on the first surface;

and/or, the orthographic projection of the heat dissipation protrusion on the first surface covers the orthographic projection of the heat generating device on the first surface.

In some embodiments, the thermally conductive filler comprises one or more of thermally conductive silicone grease, a thermally conductive pad, and an indium foil.

In some embodiments, the vacuum isothermal cavity substrate surface is formed with an oxide layer by a blackening process.

In some embodiments, the functional modules are a plurality, and a plurality of the functional modules are mounted in parallel and/or in series to the heat collector.

In some embodiments, the heat collector comprises a honeycomb heat sink.

In some embodiments, the heat collector further comprises a vacuum isothermal cavity heat dissipation plate fixed to a surface of the honeycomb heat dissipation plate or pre-buried inside the honeycomb heat dissipation plate; and the surface of the vacuum isothermal cavity heat dissipation plate exposed outside the honeycomb heat dissipation plate is a heat dissipation surface.

In some embodiments, the vacuum isothermal chamber substrate and/or the vacuum isothermal chamber heat dissipation plate comprises: the vacuum isothermal cavity is formed by the first cover plate, the second cover plate and the porous medium in a matching mode, and the porous medium is filled in the vacuum isothermal cavity.

In a second aspect, the present invention also provides a spacecraft comprising a spacecraft assembly according to any of the first aspects.

Drawings

FIG. 1 is a schematic structural diagram of a spacecraft assembly according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of another spacecraft assembly according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of another spacecraft assembly according to an embodiment of the present invention;

FIG. 4 is a schematic structural view of another spacecraft assembly according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a vacuum isothermal cavity substrate in a spacecraft assembly according to an embodiment of the invention;

fig. 6 is a schematic structural diagram of a heat dissipation plate of a vacuum isothermal cavity in a spacecraft assembly according to an embodiment of the invention.

Icon: 100-heat collector; 200-function modules; 110-a honeycomb heat dissipation plate; 120-vacuum isothermal cavity cooling plate; 210-vacuum isothermal chamber substrate; 220-a heat generating device; 230-mounting plate; 231-connection; 240-a thermally conductive filler; 210 a-heat dissipating bumps; 211-a phase change heat exchange medium; 212-a first cover plate; 213-a second cover plate; 121-a phase change heat exchange medium; 122-a first cover plate; 123-second cover plate.

Detailed Description

First, the application scenario of the present application is introduced: for high-power on-board part assemblies or modules, the traditional mode generally adopts an additional heat conduction device (such as copper bars, heat conduction locks and the like), the method needs to increase additional weight, due to the continuous improvement of integration of spacecraft assemblies, installation space for arranging related heat conduction devices is not provided in many cases, and heat can be transferred only in limited ways due to the fact that the heat conduction characteristics of materials are utilized for heat transfer, and in addition, the method can only be used for a point-to-point heat dissipation path and cannot effectively diffuse the heat.

Based on the application scene, the embodiment of the application provides a spacecraft assembly and a spacecraft, which are used for meeting the use requirement of higher power.

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. Wherein, in the description of the embodiments of the present application, "/" means or is meant unless otherwise indicated, for example, a/B may represent a or B; the text "and/or" is merely an association relation describing the associated object, and indicates that three relations may exist, for example, a and/or B may indicate: the three cases where a exists alone, a and B exist together, and B exists alone, and in addition, in the description of the embodiments of the present application, "plural" means two or more than two.

The terms "first," "second," and the like, are used below for descriptive purposes only and are not to be construed as implying or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature, and in the description of embodiments of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.

In a first aspect, as shown in fig. 1 to 5, an embodiment of the present invention provides a spacecraft assembly, including: the heat collector 100 and the functional module 200 mounted on the heat collector 100; the functional module 200 includes: a vacuum isothermal cavity substrate 210 and a heating device 220, wherein a phase change heat exchange medium 211 is arranged inside the vacuum isothermal cavity substrate 210; the vacuum isothermal cavity substrate 210 has a first surface for mounting the heat generating device 220; a thermally conductive filler 240 is filled between the first surface and the heat generating device 220.

The spacecraft assembly adopts the vacuum isothermal cavity substrate 210 to replace the traditional metal mounting frame to mount the heating device 220, the phase change heat exchange medium 211 is arranged in the vacuum isothermal cavity substrate 210, phase change such as heat absorption and gasification of a liquid heat exchange medium occurs through the phase change heat exchange medium 211, heat transfer is performed, the heat transfer coefficient is large, the heat transfer quantity is large, the vacuum isothermal cavity substrate 210 collects heat of the functional module 200 and conducts the heat to the heat collector 100 for heat dissipation, the use requirement of higher power can be met, and no additional heat conduction assembly is needed.

It can be understood that according to the heat exchange principle and the thermal environment of the spacecraft assembly in the orbit, when the high-power module in the spacecraft assembly needs to dissipate heat, because the space environment is a vacuum environment, no convective heat exchange exists, and a reasonable heat dissipation path is that heat is conducted to the radiation radiator by using the heat conduction component to radiate the heat to the space cold-black background. According to the heat transfer path analysis and the thermal resistance analysis, the smaller the number of transfer times on the heat transfer path, the smaller the temperature difference introduced due to the contact thermal resistance, and in addition, the larger the heat conductivity coefficient of the heat transfer device on the heat transfer path, the smaller the heat transfer temperature difference introduced due to the heat transfer thermal resistance. The spacecraft assembly provided in this embodiment utilizes the phase change heat transfer (large thermal conductivity) within the vacuum isothermal cavity and its workability, and proposes to utilize the vacuum isothermal cavity substrate 210 as the main component for heat transfer for the larger power devices in the spacecraft assembly.

In some embodiments, the vacuum isothermal chamber substrate 210 comprises: the first cover plate 212, the second cover plate 213 and the porous medium, wherein the first cover plate 212 and the second cover plate 213 are matched to form a vacuum isothermal cavity, and the porous medium is filled in the vacuum isothermal cavity.

In one possible implementation, as shown in fig. 5, the first cover plate 212 and the second cover plate 213 cooperate to form a vacuum isothermal chamber, a porous medium is filled inside the vacuum isothermal chamber, a phase change heat exchange medium 211 is filled inside the vacuum isothermal chamber, and phase change conduction heat occurs inside the vacuum isothermal chamber. Specifically, the heat exchange principle of the vacuum isothermal chamber substrate 210 is: the liquid at the bottom of the vacuum isothermal chamber, i.e. the phase change heat exchange medium 211, evaporates and diffuses into the vacuum isothermal chamber after absorbing the heat from the heat generating device 220, conducts the heat to the porous medium, and then condenses into liquid back to the bottom. The evaporation and condensation process circulates in the vacuum isothermal cavity rapidly, and quite high heat dissipation efficiency is achieved. Illustratively, the phase change heat exchange medium 211 may be water, acetone, alcohol, liquid ammonia, or the like.

In some embodiments, the heat dissipating bump 210a facing the heat generating device 220 is disposed on the first surface, and the heat conductive filler 240 is filled between the heat dissipating bump 210a and the heat generating device 220; and the gap between the heat generating device 220 and the heat dissipating bump 210a is smaller than the thickness of the heat conductive filler 240.

In a possible implementation manner, as shown in fig. 1 and 2, the heat generating device 220 is mounted on the vacuum isothermal cavity substrate 210 through the mounting plate 230, and the vacuum isothermal cavity substrate 210 is provided with a heat dissipating protrusion 210a on a side where the heat generating device 220 is connected, that is, a first surface, and the position of the heat dissipating protrusion 210a corresponds to that of the heat generating device 220. Illustratively, the vacuum isothermal cavity substrate 210 absorbs heat through the heat dissipation protrusions 210a, the phase-change heat exchange medium 211 inside the vacuum isothermal cavity substrate 210 absorbs heat to generate phase change such as liquid to gas, absorbs heat, the gas is transferred to the heat dissipation surface, i.e. the second surface, of the vacuum isothermal cavity substrate 210 through the porous medium, the gas is condensed to liquid and releases heat, the condensed liquid flows back to the first surface of the vacuum isothermal cavity substrate 210 through the capillary channels of the porous medium, and the back-flowed phase-change heat exchange medium 211 is heated and then is gasified again to absorb heat, conduct heat and condense heat, so that the repeated effects are achieved.

It can be appreciated that in order to increase the heat conduction rate between the heat dissipating bump 210a and the heat generating device 220, the contact surface between the heat dissipating bump 210a and the heat generating device 220 is filled with the heat conductive filler 240.

It should be noted that, in order to ensure good heat conduction between the heat dissipating bump 210a and the heat generating device 220, the heat dissipating bump 210a and the heat generating device 220 need to be in close contact with the heat conducting filler 240, and the heat conducting filler 240 is generally made of a flexible material, so that the gap between the heat generating device 220 and the heat dissipating bump 210a is smaller than the thickness of the heat conducting filler 240, and both the heat generating device 220 and the heat dissipating bump 210a can abut against the heat conducting filler 240. Illustratively, referring to fig. 1 and 2, the vacuum isothermal cavity substrate 210 and the mounting plate 230 of the heat generating device 220 are connected by a connection 231 such as a screw, and the first surface of the vacuum isothermal cavity substrate 210 is provided with a screw post; when the heat-generating device 220 is installed, the heat-conducting filler 240 can be placed or laid on the heat-dissipating protrusion 210a, and the heat-conducting filler 240 is threaded through the mounting plate 230 to be matched with the threaded column by the screw, and the distance between the heat-generating device 220 and the heat-dissipating protrusion 210a is gradually reduced along with the screwing of the screw until the heat-generating device 220 extrudes the heat-conducting filler 240, so that interference fit is realized.

In some embodiments, the orthographic projection of thermally conductive filler 240 onto the first surface covers the orthographic projection of heat-generating device 220 onto the first surface; and/or, the front projection of the heat dissipating bump 210a on the first surface covers the front projection of the heat generating device 220 on the first surface.

It should be noted that, the front projection of the heat conductive filler 240 on the first surface covers the front projection of the heat generating device 220 on the first surface, which is understood that the outer contour of the front projection of the heat conductive filler 240 on the first surface coincides with the outer contour of the front projection of the heat generating device 220 on the first surface, as shown in fig. 1; it is also understood that the orthographic projection of the thermally conductive filler 240 on the first surface is greater than the orthographic projection of the heat-generating device 220 on the first surface, as shown in fig. 2. The orthographic projection of the heat conductive filler 240 on the first surface is defined as a first projection, the orthographic projection of the heat generating device 220 on the first surface is defined as a second projection, and the outer contour of the first projection surrounds the outside of the second projection. Both the above structures can make the heat conductive filler 240 completely cover the heat generating device 220 such as a chip, avoid the generation of local hot spots of the heat generating device 220, and further reduce the contact thermal resistance.

It should be further noted that, the front projection of the heat dissipating bump 210a on the first surface covers the front projection of the heat generating device 220 on the first surface, which is understood that the outer contour of the front projection of the heat dissipating bump 210a on the first surface coincides with the outer contour of the front projection of the heat generating device 220 on the first surface, as shown in fig. 1; it is also understood that the front projection of the heat dissipating bump 210a on the first surface is larger than the front projection of the heat generating device 220 on the first surface, as shown in fig. 2. The orthographic projection of the heat dissipating bump 210a on the first surface is defined as a third projection, the orthographic projection of the heat generating device 220 on the first surface is defined as a second projection, and an outer contour of the third projection surrounds the second projection. Both the above structures can make the heat dissipation bump 210a completely cover the heat generating device 220, such as a chip, to avoid local hot spots of the heat generating device 220, and further reduce contact thermal resistance.

In some embodiments, the thermally conductive filler 240 includes one or more of thermally conductive silicone grease, a thermally conductive pad, and an indium foil.

It should be noted that, the main function of the heat conductive filler 240 is to support and conduct heat between the heat generating device 220 and the heat dissipating bump 210a, so any material that can achieve the above functions can be used to make the heat conductive filler 240, not limited to the heat conductive gel and the elastic heat conductive pad.

In some embodiments, the surface of the vacuum isothermal cavity substrate 210 is formed with an oxide layer by a blackening process.

It will be appreciated that to increase the radiative heat transfer between the devices, the outer surface of the vacuum isothermal cavity substrate 210 is painted with a black paint or is blackened. Illustratively, the surface of the vacuum isothermal cavity substrate 210 is oxidized to form an oxide layer, so as to improve emissivity. Emissivity is generally referred to herein as emissivity. Where emissivity is the ratio of the radiant flux radiated per unit area of the object surface to the radiant flux radiated by a black body at the same temperature. Emissivity of an actual object is defined as: the ratio of the radiant emittance of the object to the radiant emittance of an absolute black body at the same wavelength at the same temperature. The proximity of the actual object's thermal radiation to the blackbody thermal radiation is characterized.

In some embodiments, the functional modules 200 are plural, and the plural functional modules 200 are mounted in parallel and/or in series to the heat collector 100.

In one possible implementation, the number of functional modules 200 is plural, and as shown in fig. 1-4, the number of functional modules 200 is 3. The plurality of functional modules 200 are installed in parallel and/or in series to the heat collector 100, that is, the heat generating devices 220 in the plurality of functional modules 200 all conduct heat to the heat collector 100 through the vacuum isothermal cavity substrate 210, thereby achieving concentrated heat dissipation of the heat collector 100.

By utilizing the high heat conduction characteristic of the vacuum isothermal chamber while reducing the heat conduction components, each functional module 200 is mounted on the bottom heat collector 100 in parallel or in series, so that the heat consumption of the heat generating device 220 can be quickly and effectively conducted to the vicinity of the bottom heat collector 100 of the unit.

In some embodiments, the heat collector 100 includes a honeycomb heat sink 110.

In a possible implementation manner, in order to increase the exchange area, the inner layer structure of the heat dissipation plate of the heat collector 100 adopts a honeycomb shape, and the outer surface is covered with a metal such as an aluminum alloy skin for protection. The heat generated by the heat generating device 220 may be directly dissipated from the outer surface of the honeycomb heat dissipation plate 110 to the space environment.

In some embodiments, the heat collector 100 further includes a vacuum isothermal cavity heat dissipation plate 120, wherein the vacuum isothermal cavity heat dissipation plate 120 is fixed on the surface of the honeycomb heat dissipation plate 110 or embedded in the interior of the honeycomb heat dissipation plate 110; the surface of the vacuum isothermal cavity heat dissipation plate 120 exposed to the outside of the honeycomb heat dissipation plate 110 is a heat dissipation surface.

It should be noted that, when the spacecraft assembly has a larger power requirement, and the heat dissipation area of the honeycomb heat dissipation plate 110 does not meet the heat dissipation requirement of the spacecraft assembly, the heat collector 100 adds the vacuum isothermal cavity heat dissipation plate 120 on the basis of the honeycomb heat dissipation plate 110. The vacuum isothermal cavity heat dissipation plate 120 is internally provided with the phase change heat exchange medium 211, and phase change such as heat absorption and gasification of a liquid heat exchange medium occurs through the phase change heat exchange medium 211, so that heat transfer is performed, the heat transfer coefficient is large, the heat transfer quantity is large, and the vacuum isothermal cavity heat dissipation plate 120 performs auxiliary heat dissipation, so that the use requirement of higher power can be met.

It will be appreciated that the exterior of the honeycomb cooling plate 110 is usually made of a heat conductive metal such as aluminum, and the vacuum isothermal cavity cooling plate 120 may be directly fixed to the surface of the honeycomb cooling plate 110 by screws or other locking members, as shown in fig. 3, or a portion of the vacuum isothermal cavity cooling plate 120 may be embedded in the interior of the honeycomb cooling plate 110 in advance when the honeycomb cooling plate 110 is manufactured, so that the vacuum isothermal cavity cooling plate 120 and the honeycomb cooling plate 110 are in an integral structure, as shown in fig. 4.

It should be noted that, the exposed surface of the vacuum isothermal cavity heat dissipation plate 120 may be used as a heat dissipation surface, and the vacuum isothermal cavity heat dissipation plate 120 has a main function of increasing a radiation area, so the shape and the size of the vacuum isothermal cavity heat dissipation plate 120 are not particularly limited, and as shown in fig. 3 and 4, the shape of the vacuum isothermal cavity heat dissipation plate 120 is L-shaped, and the heat dissipation capacity is discharged to the space environment by using the area of the vacuum isothermal cavity heat dissipation plate.

In some embodiments, the vacuum isothermal cavity heat dissipation plate 120 includes: the first cover plate 122, the second cover plate 123 and the porous medium, wherein the first cover plate 122 and the second cover plate 123 are matched to form a vacuum isothermal cavity, and the porous medium is filled in the vacuum isothermal cavity.

In one possible implementation, as shown in fig. 6, the first cover plate 122 and the second cover plate 123 cooperate to form a vacuum isothermal cavity, the porous medium is filled in the vacuum isothermal cavity, the phase-change heat exchange medium 121 is filled in the vacuum isothermal cavity, and phase-change conduction heat occurs in the vacuum isothermal cavity. Specifically, the heat exchange principle of the vacuum isothermal cavity heat dissipation plate 120 is as follows: after absorbing the heat of the heat generating device 220, the liquid at the bottom of the vacuum isothermal chamber, i.e. the phase change heat exchange medium 121, evaporates and diffuses into the vacuum isothermal chamber, conducts the heat to the porous medium, and then condenses into liquid back to the bottom. The evaporation and condensation process circulates in the vacuum isothermal cavity rapidly, and quite high heat dissipation efficiency is achieved. By way of example, the phase change heat exchange medium 121 may be water, acetone, alcohol, liquid ammonia, or the like.

In the spacecraft assembly provided by the embodiment of the invention, on the heat transfer path, the heat transfer times are effectively reduced, and the heat conductivity coefficient of the heat conducting material is increased by utilizing the vacuum isothermal cavity substrate 210 to replace the traditional metal mounting frame, so that the temperature level of high-power devices for the spacecraft in the co-grouping process can be effectively reduced.

In a second aspect, embodiments of the present invention also provide a spacecraft, comprising a spacecraft assembly as in any of the embodiments of the first aspect.

It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims (10)

1. A spacecraft assembly, comprising: a heat collector and a functional module mounted on the heat collector;

the functional module includes: the vacuum isothermal cavity substrate and the heating device are arranged in the vacuum isothermal cavity substrate, and a phase change heat exchange medium is arranged in the vacuum isothermal cavity substrate; the vacuum isothermal cavity substrate is provided with a first surface for mounting the heating device; the vacuum isothermal chamber substrate comprises: the device comprises a first cover plate, a second cover plate and a porous medium, wherein the first cover plate and the second cover plate are matched to form a vacuum isothermal cavity, and the porous medium is filled in the vacuum isothermal cavity; and a heat conducting filler is filled between the first surface and the heating device.

2. The spacecraft assembly of claim 1, wherein the first surface is provided with heat dissipating protrusions facing the heat generating device, the thermally conductive filler being filled between the heat dissipating protrusions and the heat generating device; and the gap between the heating device and the heat dissipation protrusion is smaller than the thickness of the heat conduction filler.

3. The spacecraft assembly of claim 2, wherein an orthographic projection of the thermally conductive filler on the first surface covers an orthographic projection of the heat generating device on the first surface;

and/or, the orthographic projection of the heat dissipation protrusion on the first surface covers the orthographic projection of the heat generating device on the first surface.

4. A spacecraft assembly according to any of claims 1-3, wherein the thermally conductive filler comprises one or more of thermally conductive silicone grease, thermally conductive pads, indium foil.

5. A spacecraft assembly according to any of claims 1-3, wherein the vacuum isothermal cavity substrate surface is formed with an oxide layer by blackening treatment.

6. A spacecraft assembly as claimed in any of claims 1 to 3, wherein the functional modules are plural and plural of the functional modules are mounted in parallel and/or in series to the collector.

7. A spacecraft assembly according to any of claims 1-3, wherein the heat collector comprises a honeycomb heat sink.

8. The spacecraft assembly of claim 7, wherein said heat collector further comprises a vacuum isothermal cavity heat sink having a phase change heat transfer medium therein; the vacuum isothermal cavity cooling plate is fixed on the surface of the honeycomb cooling plate or is pre-buried in the honeycomb cooling plate; and the surface of the vacuum isothermal cavity heat dissipation plate exposed outside the honeycomb heat dissipation plate is a heat dissipation surface.

9. The spacecraft assembly of claim 8, wherein said vacuum isothermal cavity heat dissipation plate comprises: the vacuum isothermal cavity is formed by the first cover plate, the second cover plate and the porous medium in a matching mode, and the porous medium is filled in the vacuum isothermal cavity.

10. A spacecraft comprising a spacecraft assembly as claimed in any of claims 1-9.