MECHANICAL EVALUATIONS TO DEFINE POSSIBLE FUEL ELEMENT DESIGNS FOR THE CONVERSION OF FRM II

The Forschungs-Neutronenquelle Heinz Meier-Leibnitz (FRM II) is actively participating in the worldwide efforts on developing high-density uranium fuels in order to reduce the enrichment of fuels used in high flux research reactors. This work is part of a parameter study to define possible compatible FRM II core designs for conversion. The objective is to set up a coupled system accounting for neutronics, thermal hydraulics and mechanics and provide further numerical simulations, which are necessary to study the repercussions of every parameter on the overall fuel performance that could be changed in the course of the conversion. As a first step into a thermal hydraulics-mechanics coupling, also known as a Fluid Structure Interaction (FSI) analysis, basic and yet essential evaluations of the fuel plate's mechanical properties are made by using a rather simple coupling between Ansys CFX and Ansys Mechanical. This first analysis opens the way to more complicated and fully coupled FSI assessments.