Probabilistic Safety Assessment of ESBWR gravity driven cooling system

Aleksej KASZKO; Grzegorz NIEWIŃSKI; Michał STĘPIEŃ

Aleksej KASZKO Institute of Heat Engineering, Warsaw University of Technology, Poland
Grzegorz NIEWIŃSKI Institute of Heat Engineering, Warsaw University of Technology, Poland https://orcid.org/0000-0002-3185-5250
Michał STĘPIEŃ Institute of Heat Engineering, Warsaw University of Technology, Poland

Keywords: nuclear power plant, Probabilistic Safety Assessment, PSA, Fault Tree Analysis, FTA, GraGravity Driven Cooling System, GDCS

Abstract

According to Polish nuclear law, newly emerging nuclear facilities require probabilistic safety assessment (PSA). This article is intended to present the PSA method and to present the error tree method by which the probability of unavailability of the gravity reactor cooling system (GDCS) of the ESBWR power plant designed by GE Hitachi was determined. This work includes creatiion process of a damage tree and performing a quantitative analysis in SAPHIRE tool and estimating uncertainty using the Monte Carlo method. As a part of the work, it was shown that in the probability of failure of a single GDCS P_LINE-A line, the most important element are the basic events related in particular to the operation of service valves.