SIMULATION OF ISOTHERMAL FISSION GAS RELEASE

Abstract A fission gas release model is presented, which considers the atomic diffusion with trapping of Xe and Kr atoms generated during irradiation of the UO 2 fuel, precipitation of gas in intra and intergranular bubbles, its resolution due to impact of energetic fission fragments, interconnection of grain boundary bubbles and sweeping of gas by the grain boundary movement. The diffusion equation is solved by the finite difference method and the results compare well with isothermal experimental determinations.