Further considerations of the adiabatic exponent in steady detonation

With the exception of the detonation velocity D, few reliable measurements exist of other CJ variables. Previously we have shown (1) that the adiabatic exponent κ1=−(∂lnP1/∂lnν1)s can be obtained from accurate measurements of D, initial density ρ0, and the usually less reliable measurements of the CJ pressure P1. It was found that κ1 is solely a function of ρ0 over a wide range of ρ0. Subsequent use of κ1 in the conservation equations led to reliable determination of P1, ν1, the difference in internal energy E1−E0, and the Gruneisen coefficient Γ1=−(∂lnT1/∂lnν1)s. The present paper improves the procedures for obtaining κ1. Additionally, partial derivatives of CJ variables, along the loci of CJ states, e.g. (∂P1/∂ν1)L, (∂E1/∂ν1)E0, (∂S1/∂ν1)E0, (∂ν1/∂ν0)L, etc., were formulated. These partial derivatives may be of interest per se, and they tend to validate the observed non-dependence of κ1 on the chemical composition of explosives.