Thermal and mechanical behavior of the first wall in fusion reactor

In this study, 3D and 2D finite element models have been developed and used to analyze temperature and stress in the first wall of ITER. Results show that the contact resistance between the outer wall and cooling tube is a critical factor affecting heat transfer through the first wall. Minimum thickness greatly affected stress in the first wall. The importance of nuclear cross-section on material selection appeared to be relatively minor. Thermal creep greatly reduced the stress during the operation but increased the residual stress in the first wall. Free expansion generated much lower stress than found with higher constraint. Thus, constructing the ITER blanket system to allow free expansion of the first wall is beneficial.