A Reliability Assessment for the Decay Heat Removal System in the Sfr Using Reliability Physics Model

Abstract

Probabilistic risk assessment is expected to play a major role in the design and licensing framework for future reactors. Since the safety of a sodium-cooled fast reactor largely depends on the reliability of the decay heat removal system adopting a passive safety feature, it is indispensable to assess the reliability of the system. The existing reliability assessment methodology that uses the probability of component failures and human errors would not work for the process as the passive safety system does not consist of active components. In this study, therefore, a methodology for evaluating the reliability of the passive safety system was presented by analyzing the uncertainty of the system parameters that can affect the system failure using the reliability physics model, and the reliability of the decay heat removal system was evaluated by applying this methodology to Prototype Gen-IV Sodium-cooled Fast Reactor, which is currently under development in Korea.