Calculation of vapor composition produced by incongruent laser vaporization of uranium dioxide in vacuum
M. Brykin and M. Sheindlin
Numerical modeling of incongruent phase transitions in super stoichiometric uranium dioxide including vacuum vaporization is performed to depict a full picture of the processes both on the evaporation surface and in the material bulk – the information, which is almost impossible to get experimentally. The applied mathematical model is based on a continuous approximation for the description of mass and energy transfer in the condensed phase and under assumption of local thermodynamic equilibrium every where including phase boundaries. The model allows formation of two-phase areas with coexisting solid and liquid phases. The brief description of the applied mathematical model for incongruent evaporation is presented as well as the results of computer modeling. The results of the modeling are compared with available experimental data on temporal behavior of vapor composition during laser-inducede vaporation of super stoichiometric uranium dioxide. The possible reasons for some discrepancies are discussed.
Keywords: phase transitions