An investigation of the FGR series 40 to 52 experiments using the TRAFIC and NEFIG codes

The experiments FGR 40 to 52, performed at the Hanford Engineering Development Laboratory, are the best characterized set of out-of-pile data on the release of fission gases from solid fuel at high temperatures (> 20000C). The tests have been simulated using the TRAFIC code and the results compared with the experimental data. The agreement with overall gas release measurements is encouraging. Particular attention has been paid to the behaviour of intragranular bubbles, and the bubble sizes and concentrations have been compared with the observations. (author)