Reliability studies of decay heat removal system

Passive systems have been implemented in most of the advanced reactors in order to improve the availability of the plant. In this paper the methodology used for performing the passive system reliability analysis has been discussed. A case study on passive decay heat removal system of large sized PHWRs has also been discussed. Based on the thermal hydraulic analysis failure points have been generated and the failure surface has been developed. Finally by using the Monte Carlo simulation technique failure probability has been estimated.