Interpretation of experiments on shock compression and isentropic expansion of uranium by quantum molecular dynamics simulations

Abstract

In this work, results of quantum molecular dynamics calculations of thermodynamical properties of uranium are presented. The experiments on shock compression and subsequent isentropic expansion of porous samples of uranium are well described. Our first-principle calculations of the shock Hugoniot and release isentropes of uranium demonstrate good agreement with experimental measurements. In addition, unique information of temperature along experimental curves was obtained including supposed entries of isentropes into the two-phase liquid-gas region according to the hypothetical kinks on the experimental isentropes.