RELAP5/MOD3.3程序对非能动核电厂小破口失水事故的适用性研究

Applicability Research of RELAP5/MOD3.3 for Small Break Loss of Coolant Accident of NPP With Passive Safety System

摘要: AP1000核电厂采用非能动堆芯冷却系统来缓解小破口失水事故(SBLOCA)，缓解事故的理念是流动冷却。RELAP5/MOD3.3程序适用于传统核电厂SBLOCA研究，对于非能动电厂SBLOCA研究的适用性需重新研究与评估。本工作基于非能动电厂小破口失水事故的分析，结合RELAP5/MOD3.3的结构与模型，对其进行评估和改进。为验证改进后的RELAP5/MOD3.3的适用性，以AP1000小破口失水事故的验证试验台架APEX-1000为模拟对象，分析模拟DBA-02、NRC-05事故工况。分析结果表明，改进后的RELAP5/MOD3.3的计算结果与试验数据符合较好。

Abstract: The passive core cooling system is used in AP1000 to mitigate the small break loss of coolant accident (SBLOCA). The RELAP5/MOD3.3 code is generally applicable to the traditional NPP SBLOCA research, but for the passive NPP SBLOCA, its applicability will need further study and evaluation. Based on the analysis of the important phenomenon of the SBLOCA of the passive NPP, the RELAP5/MOD3.3 code was assessed and modified. In order to verify the applicability of the modified RELAP5/MOD3.3 code, the DBA-02 and NRC-05 cases of APEX-1000 which was the test facility for verifying AP1000 small break loss of coolant accident, were simulated. It shows good agreement between the results of the modified RELAP5/MOD3.3 code and experiment data.