Investigation of Evaluation Method of Head Plate Behaviors from Ultimate Pressure Endurance to Failure with Leakage

(3) Analysis of Leak Rate from Through Wall Crack based on Crack Opening Behavior

Abstract

In FBR plants the head plate constitutes a part of the boundary of the containment vessel (CV), therefore, it is a very important issue if the function as the boundary is maintained or not in the case of severe accident (SA). And also it is important to evaluate the leak rate from the penetrated crack of the head plate after loss of boundary function, in order to estimate the effect of released fission product (FP) out of CV. In this paper as the third step of evaluation flow from the modeling of head plate thickness distribution to the estimation of leak rate, a simplified evaluation method referred to sample leak rate test results of cracked head plate specimens after pressure endurance test is discussed.