基于CERT试验台架的PCS系统关键影响因素分析

摘要

Background: Passive containment cooling system (PCS) is part of the passive reactor safety design for cooling down the containment in accidents. Purpose: This study aims to analyze the key factors affecting the cooling capacity of PCS based on the containment safety verification via integral test (CERT). Methods: The calculating model of CERT was established using containment safety analysis program. The calculating results and the experiment results were compared to verify the model. The inner containment pressure response of double-ended cold leg guillotine (DECLG) break accident was calculated and the sensitive analysis of some parameters such as the cooling water flow, the outer shell cooling water coverage and the annulus wind speed were performed. Results: The result showed that the calculated pressure and temperature were similar to the experimental test results with a little bit higher than the latter. The maximum pressure of DECLG is 0.2661 MPa. The inner containment pressure increased significantly when the cooling water flow and the outer shell cooling water coverage decreased. The pressure decreased slightly when the annulus wind speed increased. Conclusion: The calculating model is applicable for CERT calculations, and the results are conservative. Inner containment pressure is sensitive to the cooling water flow and the outer shell cooling water coverage.%非能动安全壳冷却系统(Passive Containment Cooling System,PCS)是第三代非能动反应堆的专设安全系统之一,用于在事故情况下导出安全壳内热量.基于非能动安全壳冷却系统综合性能试验台架(Containment safety vErification via integRal Test,CERT),本文研究影响PCS系统冷却效果的关键因素.采用安全壳分析程序针对CERT试验台架进行建模和计算,将计算结果与试验结果进行了对比验证.在此基础上模拟了冷管段双端断裂事故喷放下的试验壳内压力响应,并对壳外冷却水流量、壳外冷却水膜覆盖率、环腔风速等关键参数进行了敏感性分析.结果表明,冷却剂丧失事故(Loss Of Coolant Accident,LOCA)工况下,壳内压力经历两个峰值后逐渐降低,峰值压力0.2661 MPa.壳外冷却水流量、水膜覆盖率对冷却效果影响显著,二者的降低将造成壳内压力的升高;环腔风速的增大有一定的降压作用.