Seismic Analysis of a Nuclear Reactor With Fluid Structure Interaction

In the framework of the studies on the seismic behaviour of the PWR reactor cores, models have been built to describe the dynamic behaviour of one fuel assembly, one assembly row or of the whole core. Behaviour models currently restrain the study to the central row of the core. These “One Row Models” (2D vertical models) use beam models for the assemblies and do not consider interactions between the assemblies by the fluid. Recent models consider the whole core (2D horizontal models), with the objective to describe the interactions between the different rows by the fluid. This paper presents a new step to build a complete 3D whole core model, with calculations of vertical fluid flow that can take place in a 2D “one row model”. These vertical flows leads to interactions between the assemblies, even if only one row is considered.