As dynamic loading caused by turbulent flow may affect the integrity of reactor vessel internals (RVIs), characterizing relevant features and establishing an appropriate assessment procedure are vital. This study addresses influence of turbulent flow as a problem obstructing the safe operation of RVIs. Numerical models are developed and optimized by comparing preliminary analysis data with theoretical and measured results. Systematic computational fluid dynamics analyses are conducted considering nuclear fuel assemblies. Fluctuating pressures are calculated and converted into power spectral densities (PSDs). Structural assessment is conducted by using modal analysis data, PSDs, and frequency domain-based fatigue methods. Vulnerable conditions and locations are derived from the resulting stress and fatigue damage values. Environmental effects due to neutron irradiation and primary water are also briefly discussed as areas of future research.

由于湍流引起的动态载荷可能会影响反应堆容器内部构件 (RVI) 的完整性，因此表征相关特征并建立适当的评估程序至关重要。本研究将湍流的影响作为阻碍 RVI 安全运行的一个问题来解决。通过将初步分析数据与理论和测量结果进行比较来开发和优化数值模型。对核燃料组件进行了系统的计算流体动力学分析。计算波动压力并将其转换为功率谱密度 (PSD)。结构评估是通过使用模态分析数据、PSD 和基于频域的疲劳方法进行的。脆弱的条件和位置源自由此产生的应力和疲劳损伤值。