Safety assessment for burnup effect on the heat transfer performance of nuclear fuel plate

For many research reactors, dispersion fuel plates are widely used. In dispersed fuel, the fuel particles are located in a bed of base materials that can be metal or ceramic, which improves their heat transfer properties. Study and evaluation of nuclear fuel performance are essential components for reactor safety analysis and fuel element assessment. Many parameters as temperature distribution and heat transfer in fuel plates and fuel assemblies are important in reactor safety. Due to the harsh environment inside the reactor core and the effects of radiation on the fuel elements, like the swelling of the fuel plates due to the presence of fission products that cause dimensional changes of the fuel plates must be considered in the temperature distribution and heat transfer calculations. In this article, by using the corrected model of fuel radiation induced swelling for high burnups and applying it to the heat transfer calculations by multi-physics coupling including radiation, heat, and mechanics have been performed in a multi-scale approach at mesoscopic and macroscopic scales for the fuel plate. The temperature distribution of the fuel element is obtained for the values of initial burnups to high burnups and is compared with similar works that high burnup corrections are not included on the fuel swelling model. This comparison shows that the radiation induced swelling effect in the high burnup can cause an increase of about 6˚C in temperature of the fuel plate center.