全厂断电时安全壳直接加热的概率研究

安全壳直接加热(DCH)是导致安全壳早期失效的潜在因素,本文应用基于风险导向的事故分析方法(ROAAM),对堆芯碎片中UO_2的质量和Zr的氧化份额的概率密度分布抽样,对安全壳直接加热模型TCE(Two-cell Equilibrium)编程,将抽样结果带人TCE模型中计算,得到安全壳压力峰值的累积概率分布和安全壳失效概率,研究压水堆全厂断电始发事故下轴封破口面积不同的情况对下封头失效后安全壳压力峰值的影响。其中TCE模型的输入数据由严重事故分析程序计算给出。

Study on containment direct heating probability in station blackout

Containment direct heating (DCH)is a potential factor which may cause early failure of containment. In this paper, containment peak pressure and containment failure probability in DCH process are assessed by Risk-Oriented Accident Analysis Methodology (ROAAM)using Two-Cell Equilibrium (TCE)model. The influence of the diameter length of seal-LOCA in Station Blackout (SBO )in reference plant is also analyzed. In ROAAM,probability distribution for Zirconium oxidation fraction and UO2 mass in core debris are sampled to calculate as part of the input data of TCE model. The other part of the input data of the TCE model is given by severe accident analysis program.