The core shroud is one of the most important internal components of the reactor vessel internals because it meets the neutron fluence directly emitted by the nuclear fuel. In particular, dynamic effects for an earthquake should be evaluated with respect to the neutron irradiation flux. As a prerequisite to this study, simplified and detailed finite element models are developed for the core shroud using the ANSYS Design Parametric Language. Using the El Centro earthquake, seismic analyses are performed for the simplified and detailed core shroud models. Modal characteristics are obtained and their results are used for a time history analysis. Response spectrum analyses are also performed to access the degree of seismic excitation. The results of these analyses are compared to investigate the response characteristics between the simplified and detailed core shroud models from the time history and response spectrum analyses.

堆芯护罩是反应堆容器内部最重要的内部部件之一，因为它满足核燃料直接排放的中子注量。特别是，应该根据中子辐射通量来评估地震的动力效应。作为本研究的先决条件，使用 ANSYS 设计参数语言为核心护罩开发了简化和详细的有限元模型。使用 El Centro 地震，对简化和详细的岩心罩模型进行地震分析。获得模态特征并将其结果用于时间历史分析。还执行响应谱分析以获取地震激发的程度。