Models of thermophysical properties of uranium dioxide

Physical models of specific heat at constant volume and thermal conductivity of uranium dioxide are developed based on phonon spectrum data. It is explained an abnormal growth of thermal conductivity coefficient of oxide nuclear fuel in high temperature region. It is shown that the contribution from charge carrier's degrees of freedom into observed thermal conductivity coefficient of uranium dioxide can be neglected up to melting point. Developed models of thermophysical properties do not contain fitting parameters. (paper)