Estimation of the Xenon Diffusion Coefficient in Uranium Dioxide Microfuel Kernels

On the basis of experiments on measuring the yield of gaseous fission products, the diffusion coefficient of xenon in uranium dioxide kernels at a temperature of 1100°C has been estimated. The results obtained have been compared with the results of other experimental studies on diffusion processes in uranium dioxide. The time of xenon release from the UO2 kernel at a temperature of 1100°C is estimated. It has been noted that, in order to obtain data on the diffusion activation energy and frequency coefficient, which make it possible to calculate the temperature dependence of the diffusion coefficient within the Arrhenius model, it is necessary to carry out experiments at least at two temperatures. On the basis of the results of the estimate, it has been concluded that it is necessary to take into account the diffusion transfer when calculating the amount of xenon released from the fuel kernel into the buffer layer of the microfuel element.