Detonation of commercial explosives parameters of the shock waves produced at the explosives/rock boundary by the detonation of ammonite 6ZhV charges

Abstract

If the pressure at the Jouguet point has been determined and the shock adiabatic curve of the detonation products of a given explosive charge is known, one may calculate the pressure and mass velocities at the interface with rock, the shock adiabatic curves of which are known. Determination of the detonation parameters of a charge of given density gives only one point on the shock adiabatic curve of the explosion products Uouguet point). To consTxuct the shock adiabatic curve of the detonation products, we must know the equation of their state.However, as shown by Kuznetsov et al. [1], for these purposes the power-law relation between pressure and density, of the form p = Ap n (assuming that A and n ate constant, or taking account of the n vs 0 curve), is sufficiently accurate. To obtain the dependence of the polytropic exponent on the density of the products in powerful explosives, we may use the dependence of the detonation parameters on the initial density, assuming that the composition of the products does not vary greatly [2].It was initially felt that such a procedure could be used in the case in question. However, the results of investigations in [3] revealed that the pressure and density of the explosion products do not increase markedly with increasing initial density of the explosives, whereas the polytropic exponent does show a marked increase. For comparison, Fig. 1 shows the n vs 0 curve constructed from experimental data on hexogen, based on the D vs P0 and u vs p 0 curves. This figure also gives the points for ideal detonation conditions of ammonite 6ZhV of different densities. The composition of the detonation products of ammonite 6ZhV may differ markedly from that of the detonation products of hexogen, as may be seen from the polytropic exponents at the same pressures. However, this difference is not very great for ammonite 6ZhV with density 00 = 1.0 g/cmS; for 00 = 1.45 and 1.7 g/cm ~ the analogous points are located at a considerable distance from the n vs p curve of hexogen. This difference between the polytropic exponents for ammonite 6ZhV of different initial densities is apparently due to the change in the composition of the products with the density. The change in the polytropic exponent affects the shape of the shock adiabatic curves. This may be seen from Fig. 2, which gives the shock adiabatic curves of the explosion pto~cts of ammonite 6ZhV charges with • 0 = 1.0 g/era s and d = 80 ram, with the following parameters at the Jouguet point: p, = 75 9 10 ~ kg/em z and u, = 1.62 km/see (curves I and 2, starting from point A toward u > 1.62 km/sec). Curve 1 was constructed on the assumption that n = const = 1.8, in accordance with data for charges with O0 = 1.0 g/cm3~ curve 2 was constructed with an allowance for the n vs p curve from experimental data of D(p0) and u, (p 0). Mirror reflections of the corresponding adiabatic curves (see Fig. 2, curves 1' and 2' ) were constructed on the u < 1.62 krn/sec side. It will be seen from the position of the curves that an increase in the polytropic e...