Thermal stress evaluation of tubesheet structures for double-wall-tube steam generators of FBRs, 1; Study of stress inducement mechanism

Kasahara, Naoto; Takasho, Hideki*; Ando, Masanori 

Tubesheet structures utilized in heat exchangers have complex perforated portions. For design analysis of these structures, axi-symmetric models with equivalent materials of perforated plate are conventionally adopted to simplify perforated portions. Double wall steam generators expected for commercial FBRs require new type of tubesheets, where conventional design methods are not applicable. Therefore, JAEA started research programs to develop a design by analysis method of these structures. This paper reports on the mechanism of thermal stress developments in new tubesheets with an associated paper.