Computational model of the evolution of the stress-strain state of a spherical fuel element

The problem of a spherically symmetric stress state in a spherical fuel element with a cavity at the center for collecting gaseous fission products is examined. A system of equations, which are exact within the framework of the physical model, is derived for this case, a numerical method for solving this system is proposed, and the evolution of the strain in the cladding is studied for characteristic cases. The results of numerical estimates of the temporal development of strain in the cladding are presented. 2 figures. 10 references.