LOCA事故下碳化硅复合包壳失效概率计算  

Failure probability calculations of silicon carbide composite claddings under loss-of-coolant accidents

作　　者：曹力文 易柏全 郝祖龙 CAO Liwen;YI Boquan;HAO Zulong(School of Nuclear Science and Engineering,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学核科学与工程学院,北京102206

出　　处：《核技术》2023年第9期111-116,共6页Nuclear Techniques

基　　金：中央高校基本科研业务费专项资金(No.2020MS031);北京市自然科学基金(No.1192016)资助。

摘　　要：碳化硅(SiC)复合包壳是未来轻水堆耐事故燃料(Accident Tolerant Fuel,ATF)包壳候选方案之一。本文主要研究了在失水事故(Loss Of Coolant Accident,LOCA)下双层SiC结构包壳的失效概率问题。基于SiC复合材料包壳失效概率计算方法,采用准稳态方法模拟计算了瞬态工况下的SiC复合材料包壳失效概率。通过分析各种应力在事故工况下的占比,对Weibull分布的两个特征参数进行敏感性分析;研究了不同燃耗对于失效概率的影响,模拟了在不同层厚比下包壳的失效概率。结果表明:复合层所占比例的变化、Weibull参数改变、在不同燃耗下发生LOCA事故,对于SiC复合材料包壳的瞬态失效概率都有着较为明显的影响。本文的研究有助于耐事故燃料包壳的开发与设计,为SiC复合材料包壳失效概率的进一步研究提供参考。[Background]Silicon carbide(SiC)composite claddings are candidate solutions for accident resistant fuel claddings in light water reactors.[Purpose]This study aims to estimate the failure probability of a double-layer structured SiC cladding under a loss-of-coolant accident(LOCA).[Methods]Based on a failure probability calculation method for SiC composite cladding,a quasi-steady state method was used to simulate and calculate the SiC composite cladding failure probability under transient conditions.Sensitivity analysis of the two characteristic parameters of Weibull distribution was performed by analyzing the proportion of various stresses under accident conditions.The effects of different burn-up conditions on the failure probability were investigated,and the failure probability of the cladding under different layer thickness ratios was simulated.[Results&Conclusions]Simulation results indicate that the transient failure probability of SiC composite claddings is significantly affected by changes in the proportion of the composite layer and Weibull parameter,as well as the occurrence of LOCAs under different burn-up conditions.This study makes contribution to the development and design of accident resistant fuel claddings,providing reference for further investigations on the failure probability of SiC composite claddings.

关 键 词：压水堆 碳化硅 复合包壳 失水事故 失效概率 

分 类 号：TL352.1[核科学技术—核技术及应用]