承压热冲击下压力容器断裂力学分析

摘要

Based on the requirements of latest codes and rules and the research achieve‐ments of US NRC ,the analysis methodology for reactor pressure vessel (RPV ) struc‐ture integrity under pressurized thermal shock (PTS) was presented .For a series of PTS transients ,the thermal‐hydraulic responses of a typical conventional PWR were calculated with the thermal‐hydraulic system analysis program RELAP5 ,and fracture mechanics analyses of the RPV model were calculated with the finite element analysis software ANSYS .Furthermore ,the risk assessment was performed under these PTS transients ,and the effect of RPV material embrittlement was studied . The analyses indicate that the surface flaw s and the flaw s close to the interior surface of the RPV are more vulnerable to produce crack initiation than those deeper in the RPV wall .Besides , axial flaw s are more vulnerable to produce crack initiation than circumferential flaw s under the same conditions ,and axial flaw s are much more likely than circumferential flaws to propagate through the RPV wall in medium and large diameter breaks .%依据美国核管会（NRC）最新法规要求和研究进展，阐述了压水堆核电厂反应堆压力容器（RPV）承压热冲击（PTS）最新评估方法。基于热工水力系统程序RELAP5和有限元分析软件ANSYS ，针对某传统二代压水堆核电厂模拟在PTS典型瞬态过程下热工响应行为及压力容器模型断裂力学分析，并评估不同瞬态的危险性及其随压力容器材料脆性的变化。分析表明：表面裂纹和靠近内壁面的埋藏裂纹比深埋裂纹更易发生开裂；同等条件下轴向裂纹较环向裂纹更易开裂，且大中破口事故下轴向裂纹远较环向裂纹更易贯穿壁厚。