Abstract Safety by passive systems is a key design feature for new generation Nuclear Power Plants (NPPs). The Passive Containment Cooling System (PCCS) of the AP1000 NPP is a typical passive safety system, by which the heat produced in the containment is transferred to the environment through natural circulation and atmosphere is used as ultimate heat sink. Then, the climate conditions at the plant location influence the system performance. Monte Carlo (MC) simulation of random scenarios of embedding Thermal-Hydraulic (T-H) response of the passive system is commonly used for passive safety systems reliability assessment. However, T-H codes are usually computationally burdensome, in this paper, an effective way to overcome this issue and estimate passive safety system reliability is proposed and applied to the PCCS of the AP1000 NPP, showing that the T-H model runs can be reduced for efficient reliability assessment.

中文翻译：

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一种有效的被动安全系统可靠性评估方法

摘要 被动系统的安全性是新一代核电站 (NPP) 的关键设计特征。AP1000核电厂的被动安全壳冷却系统（PCCS）是典型的被动安全系统，安全壳内产生的热量通过自然循环传递到环境中，大气作为最终的散热片。然后，工厂位置的气候条件会影响系统性能。嵌入被动系统的热-水力 (TH) 响应的随机场景的蒙特卡罗 (MC) 模拟通常用于被动安全系统的可靠性评估。然而，TH 代码通常计算量很大，在本文中，提出了一种有效的方法来克服这个问题并估计被动安全系统的可靠性，并将其应用于 AP1000 核电厂的 PCCS，