[2F10-16] Thermal Hydraulics at Accidents

[2F12] Evaluation of Fission Product Release during the NPP Severe Accident

(19)Improvement of Molybdenum Release Model in the SAMPSON Code

Ayumi Itoh¹, *Hidetoshi Karasawa¹, Marco Pellegrini¹, Masanori Naitoh¹ (1. Institute of Applied Energy)

Keywords:SAMPSON, Cesium, Molybdenum, FP release

Molybdenum release model was re-evaluated because cesium molybdate transport characteristics have large impact on cesium distribution. Evaporation rate-limiting approach from the fuel surface was introduced instead of the diffusion rate-limiting approach in the previous version of the SAMPSON code. Consequently, the new model is possible to take into account of the atmospheric condition changes during the accident progression.