Prediction of detonation and JWL eos parameters of energetic materials using EXPLO5 computer code

Abstract

The thermochemical computer code EXPLO5 has been used for simple calculations of detonation properties and energy of an important class of organic explosives, namely nitro-aromatic energetic compounds such as cast TNT and mixtures, as well as new synthesized organic nitro-aromatic explosives. This procedure is based on the chemical-equilibrium steady-state model of detonation and it uses the Becker-Kistiakowsky-Wilson (BKW) equation of state for gaseous detonation products, the ideal gas and virial equations of state of gaseous combustion products, and the Murnaghan equation of state for the condensed products. The detonation products composition in the code is calculated by applying the Gibbs energy minimization method and is designed so that the users can choose between the explosive types of constants in the BKW-EOS. The code calculates the parameters of state of the products along the shock adiabate, starting from a density of a given unreacted explosive (sub po) and then increasing it in an arbitrary chosen step up to the density of about 1.5 (sub po). It determines the Chapman-Jouget (C-J) point as a point on the shock adiabate at which Velocity of Detonation (VOD) has a minimum value. The program also calculates the coefficient in the Jones-Wilkins-Lee (JWL) equation of state along the expansion isentrope by a built in JWL fitting program, and energy available for performing mechanical work. In this paper, EXPLO5 is used to estimate the detonation parameters and JWL coefficients for TNT, NTO/TNT and Composition B explosive charges, comparison of these values to the literature values as well as those determined experimentally. The use of EXPLO5 is vital in the efforts employed by the Landward Sciences group with respect to-the determination of the same parameters experimentally.