Model of fission-product diffusion in the cores of fuel microassemblies

Questions of gas liberation from fuel materials occupy an important place among the most important problems of high temperature nuclear power. This paper addresses the need for careful study of the mechanisms of fission-product transfer both in nuclear fuel and in its protective coatings. Some results are presented of investigating the process of nuclide transfer from a number of fission products in the spherical cores of fuel microelements in the case of multiple capture by traps. A loop experiment on special equipment was performed. The diffusion of nuclides is considered in the case of an exponential energy distribution of the traps with characteristic energy. Within the framework of the defect-trap model with energydistributed traps, the experimental dependences may be well described and some important structural parameters of the core material are obtained from a comparison of the theoretical results and experimental curves