Flow-Induced Vibrations in Nuclear Steam Generators: Simulation of the AMOVI Experiment with Different FSI Approaches

Abstract

The interaction between cooling fluid and solid structures (rods, tubes) in nuclear power plants may lead to flow-induced vibrations (FIV), causing material fatigue, fretting wear, and eventually loss of component integrity. This can trigger further safety issues as well as substantial standstill costs due to longer or unplanned outages. Within the European GO-VIKING (Gathering expertise On Vibration ImpaKt In Nuclear power Generation) project, experimental and numerical efforts are performed to improve the understanding of FIV in reactor cores and steam generators, as well as to develop and validate advanced numerical approaches for their prediction. In the French CEA’s AMOVI experiment, FIV in different tube configurations, exposed to a cross-flow, are investigated. GRS performed first analyses on AMOVI using three FSI methods: the full-order model ANSYS CFX – Mechanical, the reduced-order model ANSYS CFX-MOR, and the ANSYS CFX Rigid Body approach. In addition, results generated with OpenFOAM using a model similar to the Rigid Body approach are described. The tube vibration parameters (displacements in time and frequency domains), calculated with all these methods, are discussed and then compared with experimental data. Further, conclusions are made and steps to improve the presented results are identified.