Thermomechanics of the nuclear fuel rod and multi scale and multi physics coupling on the AZTLAN platform

In this work, the elastic modulus with sintered effects of a nuclear fuel pellet from a BWR reactor is analyzed. The microstructure of the nuclear fuel pellet is a sintered material with heterogeneous characteristics, consisting of the solid phase (fuel particle) and the gas phase (space between the solid phase). The volumetric averaging method (VAM) was applied to calculate the scaled elastic modulus, which is a function of the volume fraction of the solid phase. The systematic application of VAM to the governing equations of transport phenomena at the microstructure scale leads to a valid equation at the pellet scale. The analysis presented in this work considers a symmetric and asymmetric microstructure, where the scaled modulus of elasticity was calculated. According to the tests carried out, was found that the scaled modulus is practically constant with the gas pressure, however, it presents important changes with the volume fraction of the solid phase. (author)