Extension of finite element nonlinear structural analysis system 'FINAS'; Modeling of thinning process of structures in temperature analysis

Tsukimori, Kazuyuki; Furuhashi, Ichiro*

It is important to consider the thinning process in analyzing the behavior of structures including the change of their strength when thinning of structures is significant due to corrosion etc. The thinning process has already been considered in the integrity analyses of the liner affected corrosion thinning due to leaked sodium. However, in these cases the thinning process was considered only in stress analyses not in both temperature analyses and stress analyses, since the thickness of the liner was thin. In the cases of thick structures or the structures of which temperature gradient in the thickness is expected to be large due to thermal boundary conditions, the thinning process should be considered in the temperature analyses as well as stress analyses. In this study the function of modeling of thinning process in temperature analysis was developed. The concept of the method, the formulation, installation to 'FINAS', guideline of usage and the verification of the function are described. A simplified model of corrosion problem of a tube is pick up as an example. The effecct of thinning process in temperature analysis is discussed.