Solution to a coupled problem of thermomechanical contact of fuel cell elements

A problem of mathematical modeling of a section of a fuel element (fuel element), including a number of fuel pellets and a shell fragment, in an axisymmetric formulation is considered. It is assumed that the shell is a thermoelastic-plastic body, and the tablet is a thermoelastic body, taking into account the cracking of the material. To numerically simulate the thermal and mechanical contact of tablets with each other and with the shell, various variants of the domain decomposition method were used. The results of calculations are presented, which describe the achievement of the nominal power of a section containing 10 pellets, the influence of cracking of pellets on the thermomechanical state of the fuel rod is assessed.