Abstract
The primary loop in nuclear power plants (NPPs) consists of piping and pressure vessel, which operate under a high level of pressure and temperature. During the long-term service, these sections need to have their integrity analyzed to check whether they might be prone to degradation, especially when exposed to radiation. In-service codes and standards such as the RSE-M and the ASME Section VIII enclose rules for the analysis of defects in piping systems. Although geometries for pipes are well-known and the fracture analyses methods are all today quite mature, it still takes an amount of time for structural engineers to rebuild models of different defects on piping section and the evaluation results varies with different modelling methods.
Hence, this paper provides a proof-of-concept tool for fast fracture evaluation, specific to the brittle fracture induced by thermal fatigue and radiation in the primary loop. In this application, the procedure of finite element method (FEM) analysis and fracture-related criteria is well integrated, based on the open-source FEM code code_aster and multi-tool platform SALOME. It automates several steps of primary loop section simulation, including mesh generation, calculation file configuration, post-processing and reporting results.
Furthermore, the verification and validation tests are built to ensure the robustness and reliability of the software and productivity.
