Application of the Stress-Strength Interference Model to the Design of a Thermal- Hydraulic Passive System for Advanced Reactors

摘要

A reliability-based approach to the design of a natural circulation thermal-hydraulic passive system designed for advanced reactors is proposed. The concept of functional failure, i.e., the possibility that the load will exceed the capacity in a reliability physics framework, in terms of performance parameter is introduced here for the reliability evaluation of a natural circulation passive system, designed for decay heat removal of innovative light water reactors. Water flow rate circulating through the system is selected as passive system performance characteristic parameter and the related limit state or performance function is defined. The probability of failure of the system is assessed in terms of safety margin, corresponding to the limit state function. Results help designer determine the allowable limits or set the safety margin for the system operation parameters, to meet the safety and reliability requirements.