A Complete EOS for Non-Reacted Explosives

A complete EOS for non-reactive (NR) explosives is proposed and results are given for PBX9501. The EOS uses the principal isentrope, written in finite strain form, as reference curve for a Mie-Gruneisen EOS. The principal isentrope is defined by fitting available Hugoniot data, after extrapolating it to theoretical maximum density. Temperature can be calculated at any (v,e) state, for any given variation of specific heat at vo. The improvements of this model over other proposed EOS are: 1 The inclusion of initial porosity as a variable, using the Snowplough model; 2 A higher order finite strain representation to fit the Hugoniot more accurately; 3 A second value of Gruneisen Gamma gives the correct Hugoniot asymptote; 4 More accurate temperatures can be evaluated. An improved NR EOS is needed because of the sensitivity to the EOS of SDT reaction rate models, particularly if NR temperature is a parameter.