大型先进压水堆熔融物堆内滞留初步研究

摘要

The analysis code related to molten corium in-vessel retention (IVR) was developed by taking steady state enveloping computational results in the world as references.The calculation results were verified by comparing with the results from ERI,DOE and INEEL.According to molten pool parameter analysis and uncertainty analysis,the probability of exceeding-CHF accident in large-scale advanced PWR is smaller than 7 ％ when the flow path design of ULPU-2000 configuration Ⅳ is used,but the probability that the maximum of melt thickness exceeds 15 cm is very large.If there is no other mitigation method,the pressure vessel thickness of more than 20 cm is suggested to be increased to.Heat flux distribution is the main factor that influences the molten pool behavior.It is suggested that measures should be taken to adjust the heat flux distribution of the molten corium pool for mitigating heat transfer crisis at the region near the interface between oxide zone and metal zone.%参考国外熔融物堆内滞留(IVR)稳态包络工况计算编写相关程序,并与ERI、DOE及INEEL的结果进行比较,对程序进行验证.通过对大型先进压水堆熔池参数和不确定性分析可知,如果使用ULPU-2000台架Ⅳ的流道设计,压水堆发生超CHF事故的可能性小于7％,但压力容器壁厚最大熔化量超过15 cm的可能性很大,如果没有其他缓解措施,建议将大型先进压水堆压力容器厚度增加至20 cm以上.热流分配是影响熔池行为的主要因素,建议采取措施调整熔融池热流分配,以缓解氧化物层和金属层交界面处的传热危机.