The effect of fission spikes on fission gas re-solution

Abstract
The atomic collision model of fission gas re-solution has been refined by calculating the temperature dependence of the re-solution parameter η. In this way it is shown that the atomic collision model is valid only at T ≳ 400°C whereas in oxide fuels at T ≲ 1000°C a new and more effective re-solution mechanism operates. As a new mechanism in oxide fuels the interaction of fission gas bubbles of diameters up to 500 Å with the hydrostatic pressure component of the thermoelastic stress field of fission spikes is proposed and its efficiency in the temperature range 200°C ≲ T ≲ 2200°C is discussed qualitatively. In contrast to oxides this mechanism is absent in carbide and nitride fuels and hence practically negligible fission gas re-solution should exist in these fuels at higher temperatures.