Structural Design And Thermal Shielding Characteristics Optimization Analysis Of ITER Side Correction Field Coil Test Thermal Shield System

The International Thermonuclear Experimental Reactor(ITER)program was born as a result of extensive human research on magnetic confinement tokamak devices for the early and safe use of nuclear fusion as a clean energy source.As an important part of the ITER tokamak device,the side correction field coil needs to be tested at low temperatures.As one of the key components of the cryogenic test system,the role of the thermal shield is to reduce the heat load transferred from the dewar and vacuum chamber to the side correction field coils to ensure a low-temperature operating environment for the test process.In the design of the thermal shield structure,both to meet the thermal shield strength and stiffness requirements,and to ensure that the maximum temperature difference between the surface of the thermal shield to meet the design requirements below 20 K.The main research content of this paper is as follows:Firstly,the development history of ITER and the research of thermal shield at home and abroad are introduced,and the function and structural composition of the thermal shield for side calibration field coil testing are discussed based on the summary of relevant thermal shield research.The theoretical analysis of heat transfer,fluid dynamics and heat flow coupling processes in the cooling process of the thermal shield is also presented,and the main parameters affecting the cooling performance of the thermal shield are discussed to provide a theoretical basis for the subsequent structural design,multi-physics field analysis and heat shielding performance optimization.Secondly,the structural design of the cooling screen system was carried out.In the design of the thermal shield panel,6061 aluminum alloy material was selected,and the structural dimensions of the panel were designed and verified by simulation;the crosssectional form of the cooling tube,the material of the cooling tube,and the spacing of the cooling tube arrangement were designed and determined to improve the convective heat transfer capacity of the cooling tube;the structural dimensions and material selection were made for each component of the thermal shield support structure.After that,the paper analysis of heat transfer,fluid dynamics and heat flow coupling process of thermal shield cooling process is carried out,and the parameters affecting the cooling performance of thermal shield are discussed according to the theoretical analysis results,which provide the theoretical basis for the subsequent structural design,multiphysics field analysis and optimization of plating performance.Furthermore,the focus was on multi-physics field analysis of the two major components of the thermal shield system: the thermal shield panel and the thermal shield support.After comparison with the ultimate strength of the material,it was determined that the designed thermal shield structure is safe and stable,but the surface temperature difference is too large to meet the expected design requirements.Finally,in order to improve the heat shielding performance of the thermal shield and to ensure that the temperature difference of the thermal shield surface is lower than the design requirement of 20 K,the chromium-silver coating is prepared on the thermal shield surface by magnetron sputtering and electrochemical deposition,and its performance is compared in all aspects.The test results show that the surface performance of the thermal shield after magnetron sputtering is excellent,the thermal radiation emission rate is significantly reduced,the temperature distribution is most uniform,and the maximum temperature difference of23.8K is reduced to 3K,which solves the problem of excessive temperature difference on the surface of the thermal shield and optimizes the heat shielding performance of the thermal shield.Figure [62] table [13] reference [86]...