Turbulent flow effect on integrity of pressurized RVIs

• Published in: Annals of nuclear energy Vol. 163; p. 108564
• Main Authors: Je, Sang Yun, Kim, Hyun-Gon, Chang, Yoon-Suk
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-12-2021
• Subjects: Computational fluid dynamics; Finite element analysis; Frequency domain-based fatigue evaluation; Random vibration analysis; Turbulence-induced vibration; Random vibration analysis; Finite element analysis; Computational fluid dynamics; Frequency domain-based fatigue evaluation; Turbulence-induced vibration
• ISSN: 0306-4549; 1873-2100
• DOI: 10.1016/j.anucene.2021.108564

•CFD analyses were conducted to obtain turbulence-induced vibration data.•Structural assessments were performed to determine vulnerable condition and location.•Environmental effect was discussed based on frequency domain-fatigue analysis results.
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.