Thermomechanical analysis of a lead-cooled fast reactor with a fast-running model

Abstract

The aim of this work is the development and testing of a simplified and fast-running model for thermomechanical analysis of a Lead-cooled Fast Reactor (LFR). For this work a fast-running mechanical model has been coupled with a heat transfer model previously developed, as part of AZTLAN-platform project. In a nuclear reactor, an optimal heat transfer in the fuel is needed to avoid unwanted phenomena related to sudden increases in temperature. One of the main mechanisms of deterioration of heat transfer in the fuel is the thermal expansion of the fuel and cladding since it leads to the narrowing or even blockage of the space between them causing thermal and mechanical loads that can produce fuel failure. Here, the results of the numerical calculation for stress, deformation, and radial displacement in the fuel of an LFR are presented as a function of the temperature. The simplified model was validated with a Finite Element Method peridynamics model getting consistent results.

Keywords

• Thermomechanical analysis
• Radial thermal expansion
• Heat transfer in nuclear fuel