Uncertainty analysis for source term evaluation of high temperature gas-cooled reactor under accident conditions; Identification of influencing factors in loss-of-forced circulation accidents

Honda, Yuki; Sato, Hiroyuki  ; Nakagawa, Shigeaki  ; Ohashi, Hirofumi 

There is growing interest in uncertainty analysis for probabilistic risk assessment (PRA). Our target is the uncertainty analysis method development for depressurized loss-of-forced circulation (DLOFC) accident with failure of control rod systems (CRS). As one of key elements, this paper focuses on the quantification of uncertainty for the fuel temperature which is dominant for a source term analysis. As an initial step, this paper aims to suggest a procedure to identify influencing factors which is input parameter for uncertainty analysis, and shows the results of derivation of variable parameters by expansion of dynamic equation and extraction of uncertainties in variable factors.