Detailed structural analysis of a graded TF coil winding pack for EU DEMO

摘要

The toroidal field (TF) coil system is one of the most mechanically stressed systems in a tokamak. Structural integrity of the system must be maintained on the global and on the local scale, where the stress state in each conductor jacket as well as in the insulation is to be within structural allowable limits. Solving this task head-on leads to very high computational demands. In this work a methodology for a finite element (FE) detailed analysis of a graded TF coil winding pack (WP) for EU DEMO is presented. A graded WP design option was analyzed in detail in critical locations of the coil, which were identified by an approximate, but very fast approach developed earlier. A comparison with the said approach was made to verify its applicability and limitations. The presented procedure proved to be accurate requiring only moderate computational efforts. The parametric approach allows fast implementation of design changes into the model. The procedure can be used to speed up the assessment of future design iterations of the DEMO TF coil system.