PCS表面液膜覆盖率对安全壳完整性影响分析  

The influence analysis of PCS surface liquid film coverage on the containment integrity

作　　者：石兴伟[1] 雷蕾[1] 兰兵[1] 胡健[1] 乔雪冬[1] 靖剑平[1] 

机构地区：[1]环境保护部核与辐射安全中心,北京100082

出　　处：《核技术》2017年第1期75-79,共5页Nuclear Techniques

基　　金：国家科技重大专项项目(No.2015ZX06002007)资助~~

摘　　要：钢制安全壳是防止严重事故工况下放射性物质向环境释放的最后一道屏障,因此有必要研究分析事故条件下安全壳外液膜覆盖率对安全壳完整性影响,以得到安全壳在事故工况下的失效裕度。应用非能动安全壳分析程序,建立了大功率非能动反应堆非能动安全壳冷却系统(Passive Containment Cooling System,PCS)的热工水力模型,并以冷段双端剪切事故为基准研究对象,分别研究了水分配器单一故障和出水管堵管叠加水分配器故障两种事故工况。分析结果表明,两种事故工况在液膜覆盖率大于35%时,均不会出现短期安全壳超压超温失效;事故后24 h,液膜覆盖率低于45%时,安全壳出现长期冷却失效。此次研究得出结论:在流量大于61.76 m3·h-1、安全壳液膜覆盖率大于45%时,事故发生后24 h安全壳不会失效。Background： The containment is the last shielding to protect radioactive fission products under severe accident conditions from being released to the atmosphere. Purpose： In order to figure out the failure margin under accident conditions, it is necessary to research and analyze the effects of the surface liquid film coverage on the containment integrity for a Passive Containment Cooling System （PCS）. Methods： The PCS thermal-hydraulic model has been built with passive containment analysis code in large power passive reactor. Based on the reference case of double ended guillotine （DEG） on a cold leg, both the water distribution tube failure and the spray pipe pluggage together with water distribution tube failure have been carried out, respectively. Results： The analysis results show that the containment will not fail due to overpressure and over temperature in short time in both failure cases when the water film coverage is larger than 35%, while it will fail in 24 h after accident when the results of the liquid film coverage is lower than 45%. Conclusion： It can be concluded that the containment will not fail in 24 h after accident with the liquid velocity greater than 61.76 m3-h-1 and the liquid film coverage area greater than 45%.

关 键 词：非能动安全壳分析程序 非能动安全壳 双端剪切 蒸汽主管道破裂 液膜覆盖率 

分 类 号：TL364.4[核科学技术—核技术及应用]