Abstract This paper deals with the improvement and validation of numerical tools for the simulation of design basis accidents in nuclear power plants equipped with passive safety systems. Numerical models are implemented in the framework of the 1-D thermal–hydraulic system code ATHLET developed by GRS. Experimental reference data for the validation were obtained at the INKA test facility, a model of the KERENA reactor, reproducing the passive safety systems nearly at full scale. The validation effort focuses firstly on the accuracy of the models for the single passive components, and secondly on the ability of the numerical simulation to reproduce the interaction of all components of the KERENA design under realistic conditions as reproduced in the INKA test facility. Thermal-hydraulic models are presented and validated for two passive components of the KERENA reactor: the passive pressure pulse transmitter and the pressure-controlled flooding valve. Finally, the full model of the INKA facility, including these and other passive components, is discussed and numerical results for simulations reproducing three different design basis accidents are validated by comparison with the corresponding experimental data.

中文翻译：

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具有无源系统的轻水堆设计基准事故的安全案例第 2 部分 – 数值调查

摘要 本文涉及对装有非能动安全系统的核电厂设计基准事故模拟的数值工具的改进和验证。数值模型是在 GRS 开发的一维热工液压系统代码 ATHLET 的框架中实现的。验证的实验参考数据是在 INKA 测试设施中获得的，这是一个 KERENA 反应堆模型，几乎以全尺寸再现了被动安全系统。验证工作首先侧重于单个无源组件模型的准确性，其次侧重于数值模拟在真实条件下重现 KERENA 设计的所有组件相互作用的能力，如在 INKA 测试设施中重现的那样。介绍并验证了 KERENA 反应堆的两个无源组件的热工水力模型：无源压力脉冲变送器和压力控制溢流阀。最后，讨论了包括这些和其他无源部件在内的 INKA 设施的完整模型，并通过与相应的实验数据进行比较来验证再现三种不同设计基准事故的模拟数值结果。