Equation of State Formulation for Unreacted Solid High Explosive PETN

In this paper, a generalized procedure of providing p-v-e equation of state (EOS) is developed based on the hydrostatic compression data with Birch-Murnaghan form of the isotherm. Obtained formula can be used to calculate Gruneisen EOS with arbitrary specific heat as a function of entropy, C-v(S), and arbitrary Gruneisen volume function, gamma(v). It is found that different Gruneisen function gives only slight effects on EOS and p-v shock Hugoniot. On the contrary, T-v shock Hugoniot strongly depends on C-v(S) function. Constant C-v(S) gives overestimated high shock temperature T-H, while linear C-v(S) gives much lower value, and intermediate function may give appropriate T-H values.