386. プレートフィン型熱交換器の強度解析

抄録

A plate-fin type recuperator is needed in a high thermal efficiency power generation system in HTGR coupled with closed cycle helium gas turbine, whose pressure and temperature are 6MPa and 850°C, respectively. This paper describes the results of a series of FEM stress analyses carried out to develop a new simplified structural analysis procedure for this plate-fin type heat exchanger. The procedure consists of a combination of independent analyses under pressure load, steady thermal load and transient thermal load. Then, the stress can be evaluated by a summation of these stresses. Structural characteristics of fine plate-fin structure, in particular, two bending-stress inducing mechanisms are revealed. A proposed simplified analysis method using an equivalent stiffness is very useful to obtain the stress under the steady temperature distribution load. The stress analysis results under the transient thermal loads are also given. The combined stresses are calculated and evaluated to the primary and secondary allowable stress limits.