MICE超导耦合磁体冷质量应力有限元分析

Stress analysis of superconducting coupling coil assembly for muon ionization cooling experiment

摘要:

为了确定MICE(μ介子离子化冷却实验装置)中超导耦合螺线管磁体的机械稳定性和线圈冷质量的结构安全性,采用有限元方法对磁体线圈的绕制、降温和励磁过程进行数值模拟,得出不同阶段时具有滑移面结构的超导耦合线圈冷质量横截面内的应力分布.模拟结果表明,由于较大的尺寸和较高的磁场,磁体线圈冷质量内部承受较高的应力状态;从稳定性角度分析,线圈内的横向剪切应力是影响线圈机械稳定性的关键因素;在剪切力集中的区域,尤其是绕组端部与骨架之间或绕组内径面与骨架表面之间的环氧树脂粘接区域,树脂胶在主应力和最大剪应力方向上会被拉裂,从而造成失超或锻炼效应;增加滑移面则可减小该区域的应变能,从而减小失超的可能性或锻炼次数.

Abstract:

To study the mechanical stability of the superconducting coupling solenoid magnets in the MICE(Muon Ionization Cooling Experiment) channel,stress analysis by a finite element model has been performed and presented for the whole process of coil winding,cooling down and charging.According to the simulation results,the stress within the coil assembly is relatively high due to high magnetic field and large size of the coupling magnet.The shear stress is the critical factor for the instability of the coil package.In the region of shear stress concentration,crack of epoxy resin in the direction of principal stress and the maximum shear stress will cause a quench or coil training