Structure Design and Optimization of Helium Cooling Tube for Nuclear Fusion Poloidal Coil

ObjectivesThe helium cooling tube is the core component of the fusion superconducting magnet system. It connects the superconducting magnet cooling channel and the cryogenic system, and is directly related to the operation stability of the superconducting magnet system. Since helium cooling pipes need to be welded on site, the structural design of helium pipes needs to be comprehensively considered from multiple aspects such as functional realization and on-site process operability, and reasonable solutions need to be proposed.MethodsThrough comprehensive analysis of the polar field structure of the fusion reactor, the structural optimization and pressure loss assessment of the cryogenic helium cooling tube were carried out. A comprehensive comparative analysis of the helium hole size and the optimal design of weld chamfer was carried out from the perspective of structural mechanics. The general requirements for the design criteria of the fusion reactor magnet helium cooling tube were proposed. Based on the structural mechanical analysis and pressure loss analysis of helium cooling tubes, and the comprehensive consideration of field operability, a helium cooling tube design scheme was proposed to meet the requirements of helium cooling tubes for fusion reactor magnets.ResultsAlthough short running helium cooling pipes will cause an increase in local pressure loss, which is equivalent to a conductor of 2.7 meters long, the pressure loss caused by them is basically negligible compared with the total length of the coil.ConclusionsThe adoption of the short track helium tube design scheme can not only meet the functional requirements, but also greatly improve the operability of the field process and meet the requirements of helium cooling tubes for superconducting magnets in fusion reactors.