A constant temperature chamber for space optical system, control method and application

Abstract

The present invention belongs to the field of aerospace thermal control technology, and discloses a constant temperature chamber, control method and application for a space optical system. The constant temperature chamber body is provided with a shell inner surface, and the constant temperature chamber body is provided with a shell outer surface; an electric heater and a temperature measuring element are attached to the shell outer surface, and a heat pipe is installed in the non-heating area, and the outer surface of the shell is covered with a multi-layer heat insulation component; a shell microstructure and a cavity are provided between the shell inner surface and the shell outer surface; the constant temperature chamber body is heat-conductingly connected to a radiant cold plate through a high-efficiency heat-conducting component. The present invention can achieve a constant temperature thermal environment for the operation of the optical system; the operating temperature point of the constant temperature chamber can be adjusted according to demand, and the heat transfer capacity is strong and the temperature control accuracy is high; the constant temperature chamber is a lightweight structure, which solves the weight requirement of space instruments. The constant temperature chamber of the present invention has the advantages of strong constant temperature capacity, high temperature control accuracy, high reliability, no vibration, and no effect on the imaging quality of the space optical system.

Description

Technical Field

[0001] The present invention belongs to the field of aerospace thermal control technology, and in particular relates to a constant temperature chamber for a space optical system, a control method and an application thereof. Background Art

[0002] Currently, when operating in outer space, optical remote sensing instruments are subject to both external heat sources in space and internal heat sources during instrument operation, causing the temperature of the optical system within the sensor to fluctuate with time-varying characteristics. Temperature gradients and fluctuations can cause deformation of optical components and mechanical structures, leading to boresight drift and wavefront distortion. To achieve higher image quality and accuracy, high-precision optical instruments require minimal temperature fluctuations and high stability in the operating thermal environment of the optical system.

[0003] To achieve a constant temperature operating environment for space optical remote sensors, existing technology typically involves thermally isolating optical components requiring high-precision temperature control from the overall system structure. This isolates the thermal radiation and conduction pathways from the system's internal heat source to the optical components, allowing independent temperature control of the optical system. However, a disadvantage is that the off-orbit heat flow entering the system through the optical window cannot be isolated. To ensure dimensional stability of the optical path, structural supports are often designed using materials with low thermal expansion coefficients. However, such materials typically have low thermal conductivity and high thermal resistance. As heat flows into and out of the structural components, significant temperature gradients occur within them, necessitating significant onboard resources to maintain a constant temperature.

[0004] The above analysis reveals the following problems and drawbacks of existing technologies: Optical structural supports are often constructed of materials with low thermal expansion coefficients and low thermal conductivity, resulting in high thermal resistance. Most supports are lightweight, making temperature control difficult due to the impact of the support's external shape on the design of the temperature control circuit and heat dissipation path. Furthermore, the thermal resistance and heat transfer coefficient between the structural supports and optical components are high, requiring significant resources to maintain a constant temperature solely through heat conduction. The constant temperature chamber, unaffected by external heat flow entering the instrument, provides a uniform internal environment for the optical system, resolving the challenge of precise temperature control for the structural supports and ensuring the optical system's stable operating temperature. Summary of the Invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a constant temperature chamber for a space optical system, a control method and an application.

[0006] The present invention is achieved by providing a constant temperature chamber for a space optical system, wherein the constant temperature chamber for the space optical system is provided with:

[0007] Constant temperature cabin;

[0008] The constant temperature cabin is provided with a shell inner surface, and the constant temperature cabin is provided with a shell outer surface;

[0009] The outer surface of the shell is pasted with electric heaters and temperature measuring elements, and heat pipes are installed in the non-heating area. The outer surface of the shell is covered with multi-layer thermal insulation components;

[0010] A shell microstructure and a cavity are provided between the inner surface of the shell and the outer surface of the shell;

[0011] The constant temperature cabin is thermally connected to the radiant cold plate through a high-efficiency heat conducting component.

[0012] Furthermore, the inner surface of the shell is sprayed with an optical matte coating, leaving a mechanical installation interface, and the optical matte coating adopts a thermal control coating matte black paint with an emissivity greater than 0.9.

[0013] Furthermore, the multi-layer insulation component is a 15-unit insulation component, and each unit insulation component is composed of a layer of double-sided aluminum-plated film and a layer of polyester mesh.

[0014] Furthermore, the shell microstructure is a crystal cell lattice structure, and the cavity is filled with heat transfer medium.

[0015] Furthermore, the constant temperature cabin shell and the microstructure are integrally formed.

[0016] Furthermore, the heat dissipation surface of the radiant cold plate is provided with a thermal control coating, and the non-heat dissipation surface is covered with a multi-layer heat insulation component.

[0017] Furthermore, the thermal control coating is a paste of OSR secondary surface mirror or spraying of thermal control white paint.

[0018] Furthermore, the high-efficiency heat-conducting component adopts a channel heat pipe or a loop heat pipe;

[0019] The hot end of the high-efficiency heat-conducting component is heat-conductingly installed on the surface of the constant-temperature cabin, and the cold end of the high-efficiency heat-conducting component is heat-conductingly installed on the non-heat-dissipating surface of the radiation cold plate;

[0020] The hot end of the heat pipe is thermally connected to the constant temperature chamber, and the cold end of the heat pipe is thermally connected to the radiation cold plate.

[0021] Another object of the present invention is to provide a control method for the constant temperature chamber for a space optical system, the control method comprising: utilizing the latent heat properties of the phase change material filled in the constant temperature chamber shell to reduce the sensitivity of the chamber temperature to external heat flow fluctuations; when the instantaneous external heat flow entering the chamber is too large and the high-efficiency thermal conductive component cannot quickly transfer the energy to the radiation cold plate, the phase change material filled in the constant temperature chamber shell absorbs this part of the energy by utilizing the phase change latent heat properties, thereby reducing the sensitivity of the chamber temperature to external heat flow fluctuations and providing a buffer time for the working response of the high-efficiency thermal conductive component; when the temperature of the constant temperature chamber is lower than the maintenance temperature, the temperature control circuit on the outer surface of the shell is started, PID precision temperature control is performed, and temperature compensation is performed on the constant temperature chamber to maintain the chamber at the required constant temperature state.

[0022] Another object of the present invention is to provide a space optical remote sensing instrument, which is placed in the constant temperature chamber for the space optical system.

[0023] Combining all the above technical solutions, the advantages and positive effects of the present invention are as follows: the present invention can achieve a constant temperature thermal environment for the optical system; the operating temperature point of the constant temperature chamber can be adjusted according to demand, with strong heat transfer capability and high temperature control accuracy; the constant temperature chamber is lightweight, which meets the weight requirements of space instruments; and there is no vibration source, which does not affect the imaging performance of the optical system and has high reliability. The constant temperature chamber of the present invention has the advantages of strong constant temperature capability, high temperature control accuracy, high reliability, and no vibration, which has no impact on the imaging quality of the space optical system.

[0024] In the present invention, an optical matte coating is sprayed on the inner surface of the shell, leaving a mechanical installation interface for installing a space optical system; the optical matte coating adopts a thermal control coating matte black paint with an emissivity greater than 0.9, which increases the surface emissivity, enhances the thermal radiation capacity and stray light suppression ability.

[0025] The multi-layer insulation assembly in this invention comprises 15 units, each consisting of a double-sided aluminum film and a polyester mesh to provide thermal insulation. The shell microstructure in this invention is a crystalline multicellular lattice structure, and the cavity is filled with a heat transfer medium. The heat transfer medium is a low-density, high-heat-capacity medium that is compatible with the shell material and can be a phase-change material.

[0026] In this invention, the constant-temperature chamber shell and microstructure are integrally formed to form a cavity. The heat-dissipating surface of the radiant cold plate is coated with a thermal control coating, while the non-heat-dissipating surface is covered with a multi-layer thermal insulation component. The thermal control coating is applied by gluing an OSR secondary surface mirror thermal control coating or spraying thermal control white paint. The high-efficiency thermal conductive components in this invention utilize channel heat pipes or loop heat pipes.

[0027] In this invention, the hot end of the high-efficiency thermal conductive component is thermally mounted on the surface of the constant temperature chamber, while the cold end of the high-efficiency thermal conductive component is thermally mounted on the non-heating surface of the radiant cold plate, transferring excess heat from the constant temperature chamber to the radiant cold plate. In this invention, the hot end of the heat pipe is thermally connected to the constant temperature chamber, while the cold end of the heat pipe is thermally connected to the radiant cold plate, achieving heat transfer. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] Figure 1It is a schematic diagram of the structure of a constant temperature chamber for a space optical system provided by an embodiment of the present invention.

[0030] Figure 2 Schematic diagram of heat conduction on the outer surface of a constant temperature cabin provided by an embodiment of the present invention.

[0031] Figure 3 Schematic diagram of heat conduction on the outer surface of a constant temperature cabin provided by an embodiment of the present invention.

[0032] Figure 4 This is a schematic diagram of a constant loading test curve of an external heat flux of 10 times the solar constant provided in an embodiment of the present invention.

[0033] Figure 5 This is a schematic diagram of a 10 / 15 times solar constant external heat flux cycle loading test curve provided by an embodiment of the present invention.

[0034] Figure: 1. Constant temperature chamber; 2. Multi-layer insulation assembly; 3. Radiant cold plate; 4. High-efficiency thermal conductivity assembly; 5. Electric heater; 6. Temperature measuring element; 7. Heat transfer medium; 8. Inner surface of the shell; 9. Outer surface of the shell; 10. Shell microstructure; 11. Cavity. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] In view of the problems existing in the prior art, the present invention provides a constant temperature chamber for a space optical system, a control method and an application thereof. The present invention is described in detail below with reference to the accompanying drawings. Specific embodiment one:

[0038] like Figure 1-Figure 3 As shown, the constant temperature chamber body in the constant temperature chamber for the space optical system in the present invention is a shell made of an integrally processed thermal conductive material, which is composed of a shell surface and a microstructure. The cavity formed by the two can be filled for heat transfer. After filling, the shell is sealed, and the seal is a welding seal.

[0039] The constant temperature cabin is provided with an inner shell surface 8, which is sprayed with an optical matte coating and has a mechanical installation interface for installing a space optical system; the optical matte coating adopts a thermal control coating matte black paint with an emissivity greater than 0.9, such as Z306, to increase the surface emissivity, enhance the thermal radiation capacity and stray light suppression capability.

[0040] The constant temperature chamber has an outer shell surface 9, to which an electric heater 5 and a temperature measuring element 6 are attached, and heat pipes are installed in the non-heating area. This outer shell surface 9 is covered with a multi-layer thermal insulation assembly 2, which isolates the outer surface of the constant temperature chamber from radiant heat exchange with the surrounding environment. The multi-layer thermal insulation assembly 2 comprises 15 insulation units, each consisting of a double-sided aluminum film and a polyester mesh.

[0041] Among them, a shell microstructure 10 and a cavity 11 are arranged between the inner surface 8 of the shell and the outer surface 9 of the shell; the shell microstructure 10 is a crystal-like octet lattice structure; the shell microstructure 10 and the cavity 11 are both made of the same thermal conductive material aluminum silicon and magnesium additive manufacturing, and the cavity 11 is filled with a heat transfer medium 7, which is a low-density and high-heat-capacity medium. The medium is compatible with the shell material and can be a phase change material; the heat transfer medium 7 is octadecane.

[0042] The temperature control circuit composed of the electric heater 5 and the temperature measuring element 6 adopts a PID high-precision temperature control method with a temperature control accuracy of ±0.1K.

[0043] The constant temperature chamber is thermally connected to the radiant cold plate 3 via a high-efficiency thermal conductive component 4. The heat dissipating surface of the radiant cold plate 3 is coated with a thermal control coating, while the non-heat dissipating surface is covered with a multi-layer thermal insulation component 2. The thermal control coating is either an OSR secondary surface mirror thermal control coating or sprayed with white paint. The high-efficiency thermal conductive component 4 uses an Ω-shaped 10*50 grooved heat pipe or a loop heat pipe. The hot end of the heat pipe is thermally connected to the constant temperature chamber, and the cold end is thermally connected to the radiant cold plate 3. The hot end of the high-efficiency thermal conductive component 4 is thermally connected to the constant temperature chamber surface, while the cold end is thermally connected to the non-heat dissipating surface of the radiant cold plate. Specific embodiment two:

[0045] The difference between this embodiment and the first embodiment is that the constant temperature chamber is a shell made of a thermally conductive material as a whole. The shell and the microstructure are made of different thermally conductive metal materials. The shell surface material is aluminum alloy LY12, and the microstructure material is copper alloy. The microstructure and the shell are integrated by low-temperature brazing. The cavity formed by the two is filled with the phase change material tetradecane. After filling, the liquid filling port is welded and sealed.

[0046] The working principle of the present invention is as follows: the latent heat properties of the phase change material filled in the constant temperature cabin shell are utilized to reduce the sensitivity of the cabin temperature to external heat flow fluctuations; when the instantaneous external heat flow entering the cabin is too large and the high-efficiency thermal conductive component cannot quickly transfer energy to the radiation cold plate, the phase change material filled in the constant temperature cabin shell utilizes the phase change latent heat properties to absorb this part of energy, thereby reducing the sensitivity of the cabin temperature to external heat flow fluctuations and providing a buffer time for the working response of the high-efficiency thermal conductive component; when the temperature of the constant temperature cabin is lower than the maintenance temperature, the temperature control circuit on the outer surface of the shell is started, and PID precise temperature control is performed to perform temperature compensation on the constant temperature cabin, so that the cabin is maintained at the required constant temperature state.

[0047] The specific embodiment 1 was simulated and tested, and the simulation results and experimental data are shown in the table below.

[0048] Filling fluid Thermal load Imposition of Ambient temperature Maximum cabin temperature Minimum cabin temperature Temperature gradient 18-Alkane 10 / 15 times the solar constant Periodic loading 20.1℃ 29.0℃ 28.9℃ 0.1℃ none 10 / 15 times the solar constant Periodic loading 20.1℃ 44℃ 34.9℃ 9.1℃

[0049] In the description of the present invention, unless otherwise specified, "plurality" means two or more; terms such as "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," and "tail" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0050] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with this technical field within the technical scope disclosed by the present invention and within the spirit and principles of the present invention should be covered by the scope of protection of the present invention.

Claims

1. A method for controlling a constant temperature chamber for a space optical system, characterized in that: The constant temperature chamber for the space optical system is provided with: Constant temperature cabin; The constant temperature cabin is provided with a shell inner surface, and the constant temperature cabin is provided with a shell outer surface; The outer surface of the shell is pasted with electric heaters and temperature measuring elements, and heat pipes are installed in the non-heating area. The outer surface of the shell is covered with multi-layer thermal insulation components; A shell microstructure and a cavity are provided between the inner surface of the shell and the outer surface of the shell; The shell microstructure is a crystal cell lattice structure, the cavity is filled with a heat transfer medium, and the heat transfer medium is a phase change material; The constant temperature cabin is thermally connected to the radiant cold plate through a high-efficiency heat conducting component; The inner surface of the shell is sprayed with an optical matte coating, which uses a thermal control coating matte black paint with an emissivity greater than 0.9 to increase the surface emissivity, enhance the thermal radiation capacity and stray light suppression capability; The control method includes: placing the space optical remote sensing instrument in the constant temperature cabin for the space optical system; The latent heat properties of the phase change material filled in the constant temperature cabin shell are utilized to reduce the sensitivity of the cabin temperature to external heat flow fluctuations; when the instantaneous external heat flow entering the cabin is too large and the energy entering the cabin is higher than the heat storage capacity of the phase change material, the excess heat in the constant temperature cabin is transferred to the radiant cold plate through the high-efficiency heat conduction component; when the temperature entering the constant temperature cabin is lower than the maintenance temperature, the electric heater on the outer surface of the cabin is started to compensate the temperature of the constant temperature cabin, so that the cabin is maintained at the required constant temperature state.

2. The method for controlling a constant temperature chamber for a space optical system according to claim 1, wherein: A mechanical installation interface is reserved on the inner surface of the shell.

3. The method for controlling a constant temperature chamber for a space optical system according to claim 1, wherein: The multi-layer thermal insulation component is a 15-unit thermal insulation component, and each unit thermal insulation component is composed of a layer of double-sided aluminum-plated film and a layer of polyester mesh.

4. The method for controlling a constant temperature chamber for a space optical system according to claim 1, wherein: The constant temperature cabin shell and the microstructure are integrally formed.

5. The method for controlling a constant temperature chamber for a space optical system according to claim 1, wherein: The heat dissipation surface of the radiant cold plate is provided with a thermal control coating, and the non-heat dissipation surface is covered with a multi-layer heat insulation component.

6. The method for controlling a constant temperature chamber for a space optical system according to claim 5, wherein: The thermal control coating is a thermal control coating applied by pasting an OSR secondary surface mirror or spraying white paint.

7. The method for controlling a constant temperature chamber for a space optical system according to claim 5, wherein: The high-efficiency heat conduction component adopts Ω-type 10*50 groove heat pipe or loop heat pipe; The hot end of the high-efficiency heat-conducting component is heat-conductingly installed on the surface of the constant-temperature cabin, and the cold end of the high-efficiency heat-conducting component is heat-conductingly installed on the non-heat-dissipating surface of the radiation cold plate; The hot end of the heat pipe is thermally connected to the constant temperature chamber, and the cold end of the heat pipe is thermally connected to the radiation cold plate.

Images