A primary gravitational wave detection telescope thermal control system design method
Through a closed-loop design process and multiphysics simulation, the systematic problem of thermal control design for the original gravitational wave telescope was solved, achieving precise matching and stable operation of multi-level temperature zones, thus ensuring the efficient operation of the detector.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INST OF HIGH ENERGY PHYSICS CHINESE ACAD OF SCI
- Filing Date
- 2026-04-16
- Publication Date
- 2026-07-10
AI Technical Summary
The existing thermal control design of primordial gravitational wave telescopes lacks a systematic iterative optimization process, making it difficult to comprehensively assess the temperature distribution and thermal deformation under the coupling effect of multiple physical fields, which affects the stable operation and accuracy requirements of the detector in extremely low temperature environments.
A closed-loop design process is adopted, including structural design, heat leakage calculation, thermo-mechanical coupling simulation and index iteration. The thermo-mechanical coupling model is established using Comsol multiphysics simulation software to perform multiphysics simulation and iterative optimization, ensuring accurate matching and stable operation of each component in multiple temperature ranges.
The precise matching and optimized design of the thermal control system of the primordial gravitational wave telescope were achieved, ensuring the stable operation of the detector in extremely low temperature environments and meeting the optical path accuracy requirements, thereby improving the reliability and efficiency of the design.
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Figure CN122365615A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of primordial gravitational wave detection technology, specifically relating to a design method for a thermal control system of a primordial gravitational wave detection telescope. Background Technology
[0002] Primordial gravitational waves originate from spacetime quantum fluctuations in the early stages of the Big Bang. They not only verify Einstein's spacetime theory but also provide the most powerful experimental test of theories about the origin of the universe, representing a breakthrough in the study of the fundamental physical processes of the universe's origin and evolution. Breakthroughs are urgently needed in the independent research and development of core technologies to develop a primordial gravitational wave telescope system with independent intellectual property rights, thereby promoting the development of this field.
[0003] The core detector components of the Primordial Gravitational Wave Telescope need to operate continuously within a 100mK temperature range. A reasonable and effective thermal control system is crucial to ensuring that all components of the entire telescope system operate within their normal operating temperature range and maintain stable operation, directly affecting the achievement of the detection target. Due to the complex structure of the telescope system, involving multi-level temperature ranges (300K, 50K, 4K, 1K, and 100mK) of progressive insulation and cooling, the system has various sources of heat leakage, including thermal radiation, support conduction, residual gas conduction, cable heat leakage, and component self-heating. The thermal properties and optical parameters of the materials of each component change significantly with temperature, and the thermal control effect is coupled with the structural mechanical properties, making the design extremely challenging.
[0004] Existing thermal control designs often rely on empirical formulas and single-physics field analysis, making it difficult to comprehensively assess temperature distribution and thermal deformation under the coupling effects of multiple physics fields, and lacking a systematic iterative optimization process. For telescope thermal design, there is an urgent need to conduct systematic design and numerical simulation, and to iteratively adjust according to design changes, leaving margins, thereby determining further optimizations of the thermal design to ensure stable operation of the telescope in extremely low-temperature environments and to meet detection accuracy requirements. Summary of the Invention
[0005] To address the aforementioned technical problems, this invention provides a design method for the thermal control system of a primordial gravitational wave telescope. By establishing a closed-loop design process of "structural design - heat leakage calculation - thermo-structure coupling simulation - index iteration," the precise matching and optimized design of the multi-level temperature zone thermal control system of the primordial gravitational wave telescope is achieved.
[0006] To achieve the above objectives, the present invention adopts the following technical solution:
[0007] A design method for a thermal control system of a primordial gravitational wave detection telescope, comprising:
[0008] Step S1: Based on the target requirements of the original gravitational wave telescope, the receiver body adopts a three-layer nested structure, including a 300K shell, a 50K shielding tube and a 4K shielding tube, with each layer connected by a G-10 heat insulation component.
[0009] Step S2: Analyze the cooling requirements of the receiver body, calculate the system heat leakage including thermal radiation, support heat conduction, residual gas heat leakage, cable heat leakage and component self-heating, and determine the cooling power of the selected cooling mechanism.
[0010] Step S3: Use multiphysics simulation software to establish a thermo-mechanical coupling model of the receiver structure. Use solid heat transfer, surface-to-surface radiation and solid mechanics modules to perform thermo-mechanical coupling simulation to obtain the temperature field distribution and thermal deformation of each component.
[0011] Step S4: Compare the simulation results with the target requirements. If the results meet the target temperature range and structural safety factor requirements, proceed to step S5. If a deviation occurs, return to steps S2-S3 for iterative optimization.
[0012] Step S5: Determine the thermal control implementation plan based on the design and analysis results.
[0013] Furthermore, in step S1, the 300K outer shell material of the three-layer nested structure is aluminum alloy 6061, and the 50K shielding tube and 4K shielding tube material is aluminum alloy 1100.
[0014] Furthermore, in step S2, the calculation of thermal radiation includes non-aperture thermal radiation and aperture thermal radiation. Non-aperture thermal radiation is calculated based on the surface area of the shielding cylinder, surface emissivity, and the number of layers of multilayer thermal insulation material. Aperture thermal radiation is calculated based on the lens area, transmittance, and temperature difference.
[0015] Furthermore, in step S2, the heat conduction of the support is calculated based on the thermal conductivity of the support material, the heat transfer cross-sectional area, and the temperature gradient along the conduction direction, while the residual gas heat leakage is calculated based on the gas pressure, the effective heat exchange area, and the temperature difference between adjacent shielding cylinders.
[0016] Furthermore, in step S2, the selected refrigerator includes two stages: the front stage uses a pulse tube refrigerator to handle the 50K and 4K temperature range, and the rear stage uses a dilution refrigerator to handle the 1K and 100mK temperature range. The cooling capacity of the dilution refrigerator is transferred to the focal plane detector assembly through the cold finger and copper braid.
[0017] Furthermore, in step S3, the thermal boundary conditions of the thermo-structure coupling simulation include solar transmitted radiation and absorbed heat loss of each level of filter and lens, cable self-heating and thermometer self-heating, and contact thermal resistance is set between the lens and aluminum alloy contact surface and between aluminum alloys.
[0018] Furthermore, in step S3, the mechanical boundary conditions of the thermo-mechanical coupling simulation include the fixed constraint at the bottom of the receiver, the tilted gravity load borne by the entire telescope, and the pressure difference generated by the atmospheric pressure and the internal vacuum state on the surface of the outer thermostat.
[0019] Furthermore, in step S4, the structural safety factor requirement is that the stress value of each component of the receiver does not exceed one-third of the material yield stress, and the strain value caused by thermal deformation meets the optical path accuracy requirements of optical path eccentricity less than 0.2 mm and tilt angle less than 0.2 degrees.
[0020] In a second aspect, the present invention provides an electronic device, comprising: one or more processors; and a memory for storing one or more programs; wherein, when the one or more programs are executed by the one or more processors, the one or more processors implement the aforementioned design method for a thermal control system of a primordial gravitational wave detection telescope.
[0021] Thirdly, the present invention provides a computer-readable storage medium having executable instructions stored thereon, which, when executed by a processor, enable the processor to implement the aforementioned design method for a thermal control system of a primordial gravitational wave detection telescope.
[0022] The beneficial effects of this invention are as follows:
[0023] Systematic thermal control design process: This invention proposes a complete thermal control system design method, which forms a closed-loop design process from initial structural determination, cooling demand analysis, multi-physics simulation to iterative optimization, effectively improving the reliability and efficiency of thermal control design.
[0024] Multiphysics coupling simulation analysis: This invention utilizes Comsol multiphysics simulation software to establish a thermo-solid coupling model, comprehensively considering the effects of multiple physical fields such as solid heat transfer, surface-to-surface radiation, and solid mechanics. It can accurately predict the temperature field distribution and thermal deformation of each component, overcoming the limitations of traditional empirical formulas and single-physics field analysis.
[0025] Precise heat leakage analysis and cooling matching: This invention systematically analyzes various sources of heat leakage in telescope receivers, including thermal radiation, support conduction, residual gas heat leakage, and cable heat leakage, and establishes a complete heat leakage calculation system to achieve precise matching of cooler selection and cooling power.
[0026] Rigorous iterative optimization of indicators: This invention compares simulation results with design indicators and performs targeted iterative optimization on aspects that do not meet the requirements, ensuring that the final design meets the requirements of the target temperature range, structural safety factor and optical path accuracy, thus providing a reliable guarantee for the stable operation of the primordial gravitational wave telescope in an extremely low temperature environment. Attached Figure Description
[0027] Figure 1 This is a schematic diagram of a design method for a thermal control system of a primordial gravitational wave telescope according to the present invention.
[0028] Figure 2 This is a structural diagram of a primordial gravitational wave telescope according to the present invention. Detailed Implementation
[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0030] This invention discloses a design method for a thermal control system of a primordial gravitational wave telescope, such as... Figure 1 As shown, the system includes a multi-zone thermostat (300K, 50K, 4K), a deep cryogenic cooling system, a flexible heat-conducting component, and a receiver main body. The 4K thermostat also includes... Figure 1 The components for the 1K and 100mK temperature zones are shown, and neither the 1K nor 100mK zones are hermetically sealed structures. The cryogenic cooling system consists of a dilution refrigerator (DR), including an internal system and an external system. The internal system includes a pre-cooling unit and a dilution cooling unit. The external system includes a gas circulation and control system, a compressor and chiller, and a temperature control and measurement system. The receiver main body includes a microwave optical path subsystem, a focal plane subsystem, and a room temperature electronics system. The steps of the thermal control system design method described in this invention are as follows:
[0031] Step S1. Based on the original requirements of the gravitational wave telescope, the structure, size, quantity, materials, and connection methods of each component of the telescope receiver were initially determined. The receiver body was determined to adopt a three-layer nested structure, including a 300K outer shell, a 50K shielding tube, and a 4K shielding tube, with each layer connected by G-10 thermal insulation components.
[0032] Here, we take the following indicator constraint as an example: Figure 2 As shown, the receiver of the Primordial Gravitational Wave Telescope is provided with cooling by a dilution cooler (DR) as the cold source. It adopts a multi-infrared filtering scheme in the axial direction and a three-layer shielding structure in the radial direction for progressive heat insulation. Ultimately, it achieves the goal of the optical components operating in the 4K temperature range and the focal plane detector operating in the 100mK temperature range.
[0033] Based on the target detection requirements of the original gravitational wave telescope, the receiver's main structure was designed to minimize heat leakage. The receiver features a three-layer nested structure. The outermost 300K shell is vacuum-sealed and made of 6061 aluminum alloy. The inner 50K and 4K shielding tubes are made of 1100 aluminum alloy, progressively blocking radial radiation heat leakage. To further reduce conductive heat leakage, specially designed G-10 thermal insulation components are used to connect the 300K, 50K, and 4K shielding tubes, meeting both mechanical strength and thermal insulation requirements.
[0034] The telescope employs a dual-lens refractive optical path system. The microwave optical path system uses two alumina ceramic lenses to refract incident light, held in place by an aluminum 1100 ring and connected to the interior of a 4K shielding cylinder. The TES detector is sensitive to thermal noise and requires operation within a 100mK temperature range. A multi-layer infrared filtering structure is designed from the focal plane to the window, including nylon filters, alumina ceramic filters, and multi-layer infrared filters (Zotefoam). While meeting transmittance requirements, layer-by-layer filtering is implemented to reduce heat radiated to the optical components. To reduce radial radiation heat leakage, multi-layer thermal insulation material (MLI) is used for insulation between the three shielding cylinders.
[0035] The focal plane TES detector assembly is mounted on a 4K shielding cylinder, and the ultra-fine carbon fiber rod assembly is connected layer by layer with thermal insulation to reduce heat leakage from the mK temperature range to the 4K temperature range.
[0036] The entire receiver's cooling source utilizes a stable, high-capacity DR (Digital Cooler). Due to the unique operating principle of the DR cooler, it is installed at a 30° angle to the receiver. During telescope observation, the DR axis must be maintained within ±15° of the vertical direction for the DR to function properly. The DR's 100mK disk is located close to the focal plane detector. The DR's 1K and 100mK disks are connected to cylindrical cooling fingers on the 1K and 100mK rings of the focal plane TES (Transient Electro-Optical Array) detector assembly. These cooling fingers are connected by copper braids to transfer cooling energy, thereby cooling the focal plane TES detector assembly.
[0037] Step S2. Perform thermal design on the primordial gravitational wave telescope, analyze the cooling requirements of the telescope receiver, calculate the system heat leakage including thermal radiation, support heat conduction, residual gas heat leakage, cable heat leakage and component self-heating, and determine the cooling power of the selected cooling mechanism.
[0038] Specifically, the telescope receiver operates under a high vacuum. The heat load (sources of system heat leakage) mainly includes thermal radiation, support heat conduction, residual gas (rare gas) heat leakage, cable heat leakage, and heat leakage from the low-noise amplifier and other components. Thermal radiation includes both aperture heat leakage and non-aperture heat leakage. Table 1 below shows the calculation formulas for several types of heat leakage.
[0039] Table 1
[0040]
[0041] Calculations show that the total heat load (heat leakage) for the telescope receiver at 50K and 4K is estimated to be 20.97W and 1.47W, respectively, with a heat leakage of 109.9nW at 1K and 27.3nW at 100mK. To meet these cooling requirements, a PT-420RM pulse tube refrigerator was ultimately selected as the pre-cooling stage for the DR (Diverterless Radio Refrigerator), responsible for cooling the 50K and 4K stages, with cooling power of 50W@50K and 1.8W@4K. The DR's distiller and mixing chamber stages are responsible for cooling the 1K and mK stages, with cooling power of 20mW@1K and 100μW@100mK, respectively.
[0042] Step S3. Use Comsol multiphysics simulation software to simplify the structure of the original gravitational wave telescope receiver, establish a thermo-solid model and boundary conditions, and use modules such as solid heat transfer, surface-to-surface radiation and solid mechanics to perform thermo-solid coupling simulation to obtain the temperature field distribution and thermal deformation of each component.
[0043] Specifically, the original gravitational wave telescope structural model was simplified and imported into Comsol multiphysics simulation software to establish a thermo-structure coupling simulation model. After adding solid heat transfer, solid mechanics, and surface-to-surface radiation modules, thermal and mechanical boundary conditions were applied to each component of the system. Thermal boundary conditions included solar transmission radiation and absorbed heat loss for each filter and lens stage; self-heating of cables and thermometers was added at their corresponding installation positions on the receiver; heat leakage due to heat conduction and thermal radiation from the upper and lower temperature surfaces was calculated by the software; and the calculation of thermal radiation from heat conduction involved setting material thermophysical parameters and surface optical parameters. Contact thermal resistance was set between the lens and aluminum alloy, and between aluminum alloys. Mechanical boundary conditions included setting a fixed constraint at the bottom of the receiver, the entire telescope being subjected to a 45° gravity, a 300K outer shell surface subjected to half an atmosphere of pressure, and an internal vacuum state. After setting these parameters, a mesh was created and its mesh independence was verified. Two types of meshes, free tetrahedrons and free hexahedrons, were used for mesh generation, and the calculation results under different mesh counts were compared. Finally, simulation calculations were performed to obtain the component temperature field distribution and the system stress-strain results.
[0044] Step S4. Compare the temperature field and stress-strain values obtained from the simulation with the design specifications. If they meet the target temperature range, proceed to step S5. If there is a deviation from the design specifications, continue with steps S2-S3 until the target specifications are met.
[0045] This design scheme, after numerous iterations, finally met the target design requirements. Simulation results showed that the temperature of the TES detector component was within the 100mK temperature range, the stress value of the receiver component was less than 1 / 3 of the yield stress required by the safety factor, and the strain value met the requirements of optical path eccentricity < 0.2mm and tilt angle < 0.2°.
[0046] Step S5. Determine the thermal control implementation plan based on the above design and analysis results.
[0047] The simulation results confirmed the feasibility of the thermal design scheme, and thermal control was implemented according to the design scheme in the later stage.
[0048] In a second aspect, the present invention provides an electronic device, comprising: one or more processors; and a memory for storing one or more programs; wherein, when the one or more programs are executed by the one or more processors, the one or more processors implement the aforementioned design method for a thermal control system of a primordial gravitational wave detection telescope.
[0049] Thirdly, the present invention provides a computer-readable storage medium having executable instructions stored thereon, which, when executed by a processor, enable the processor to implement the aforementioned design method for a thermal control system of a primordial gravitational wave detection telescope.
[0050] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A design method for a thermal control system of a primordial gravitational wave detection telescope, characterized in that, include: Step S1: Based on the target requirements of the original gravitational wave telescope, the receiver body adopts a three-layer nested structure, including a 300K shell, a 50K shielding tube and a 4K shielding tube, with each layer connected by a G-10 heat insulation component. Step S2: Analyze the cooling requirements of the receiver body, calculate the system heat leakage including thermal radiation, support heat conduction, residual gas heat leakage, cable heat leakage and component self-heating, and determine the cooling power of the selected cooling mechanism. Step S3: Use multiphysics simulation software to establish a thermo-mechanical coupling model of the receiver structure. Use solid heat transfer, surface-to-surface radiation and solid mechanics modules to perform thermo-mechanical coupling simulation to obtain the temperature field distribution and thermal deformation of each component. Step S4: Compare the simulation results with the target requirements. If the results meet the target temperature range and structural safety factor requirements, proceed to step S5. If a deviation occurs, return to steps S2-S3 for iterative optimization. Step S5: Determine the thermal control implementation plan based on the design and analysis results.
2. The design method for a thermal control system of a primordial gravitational wave detection telescope according to claim 1, characterized in that, In step S1, the 300K outer shell material of the three-layer nested structure is aluminum alloy 6061, and the 50K shielding tube and 4K shielding tube material is aluminum alloy 1100.
3. The design method for a thermal control system of a primordial gravitational wave detection telescope according to claim 1, characterized in that, In step S2, the calculation of thermal radiation includes non-aperture thermal radiation and aperture thermal radiation. Non-aperture thermal radiation is calculated based on the surface area of the shielding cylinder, surface emissivity, and the number of layers of multilayer thermal insulation material. Aperture thermal radiation is calculated based on the lens area, transmittance, and temperature difference.
4. The design method for a thermal control system of a primordial gravitational wave detection telescope according to claim 1, characterized in that, In step S2, the heat conduction of the support is calculated based on the thermal conductivity of the support material, the heat transfer cross-sectional area, and the temperature gradient along the conduction direction. The residual gas heat leakage is calculated based on the gas pressure, the effective heat exchange area, and the temperature difference between adjacent shielding cylinders.
5. The design method for a thermal control system of a primordial gravitational wave detection telescope according to claim 1, characterized in that, In step S2, the selected refrigerator includes two stages: the front stage uses a pulse tube refrigerator to cool the 50K and 4K temperature ranges, and the rear stage uses a dilution refrigerator to cool the 1K and 100mK temperature ranges. The cooling capacity of the dilution refrigerator is transferred to the focal plane detector assembly through the cold finger and copper braid.
6. The design method for a thermal control system of a primordial gravitational wave detection telescope according to claim 1, characterized in that, In step S3, the thermal boundary conditions of the thermo-solid coupling simulation include solar transmission radiation and absorbed heat loss of each level of filter and lens, cable self-heating and thermometer self-heating, and contact thermal resistance is set between the lens and aluminum alloy contact surface and between aluminum alloys.
7. The design method for a thermal control system of a primordial gravitational wave detection telescope according to claim 1, characterized in that, In step S3, the mechanical boundary conditions of the thermo-mechanical coupling simulation include the fixed constraint at the bottom of the receiver, the tilted gravity load borne by the entire telescope, and the pressure difference generated by the atmospheric pressure and the internal vacuum state on the surface of the outer thermostat.
8. The design method for a thermal control system of a primordial gravitational wave detection telescope according to claim 1, characterized in that, In step S4, the structural safety factor requirement is that the stress value of each component of the receiver does not exceed one-third of the material yield stress, and the strain value caused by thermal deformation meets the optical path accuracy requirements of optical path eccentricity less than 0.2 mm and tilt angle less than 0.2 degrees.
9. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs; When one or more programs are executed by the one or more processors, the one or more processors implement the thermal control system design method for a primordial gravitational wave detection telescope as described in any one of claims 1-8.
10. A computer-readable storage medium, characterized in that, It stores executable instructions that, when executed by a processor, enable the processor to implement the thermal control system design method for a primordial gravitational wave detection telescope as described in any one of claims 1-8.