首页|Fission Product Release Behavior in LBE-Cooled Fast Reactor Fuel Element: Code Development, Validation, and Application
Fission Product Release Behavior in LBE-Cooled Fast Reactor Fuel Element: Code Development, Validation, and Application
Kou, Dr. Minghai Guo, Dr. Ning Chen, Dr. RH Jiang, Dr. Pinting Wu, Dr. Yingwei Tian, Prof. Wenxi
Fission Product Release Behavior in LBE-Cooled Fast Reactor Fuel Element: Code Development, Validation, and Application
Fission Product Release Behavior in LBE-Cooled Fast Reactor Fuel Element: Code Development, Validation, and Application
摘要
Fission product release from fuel pellets to the rod free volume is important for evaluating in-gap source terms and fuel rod performance under intact cladding conditions. However, its behavior in lead-bismuth cooled fast reactors remains insufficiently understood. In this study, a mechanistic fission product migration and release model was developed and implemented into the fuel performance code FROBA. The model accounts for intragranular diffusion, grain boundary bubble growth and recoil release. The intragranular diffusion equation was solved using the Polypole algorithm. The model was validated against fission-gas irradiation data from the CONTACT and SUPERFACT experimental programs, and then applied to a representative MYRRHA fuel rod to investigate fission product release behavior. The results show general agreement with the available fission-gas experimental and reference data; the treatment of volatile fission products remains to be validated. The release-to-birth ratio of different nuclides is strongly influenced by both diffusion and radioactive decay, and decreases with increasing decay constant under otherwise identical conditions. The developed model provides a physically based tool for preliminary prediction of fission-gas release and gap inventories in lead-bismuth-cooled fast-reactor fuel rods prior to cladding failure.