Modeling of radionuclides release during cask leakage tests of failed fuel rods

The developed code RTOP–LT models mass transport of water and dissolved radionuclides inside failed fuel rods during cask leakage tests. Main physical models relevant for leakage testing and their numerical implementations in the code RTOP–LT are presented in the paper. The code has been successfully verified against small-scale experiments at the CASK facility. As an example the code RTOP–LT is applied to development and validation of leakage test technique with pressure cycling.