Studies on Empirical Approaches for Estimation of Detonation Velocity of High Explosives

Despite many computer based codes like CHEETAH, TIGER, RUBY, BKW, etc. the velocity of detonation (VOD) for explosive molecules and explosive mixtures (formulations) is estimated by several empirical formulations. This article discusses various approaches for the estimation of the velocity of detonation by empirical mathematical equations. The formulation proposed by Kamlet in 1968 is the oldest one and it is confirmed to be more reliable by many subsequent researchers. The method proposed by Rothstein (1978), Xiong (1985), Stein (1990), Keshavarz (2006) are discussed and compared for conventional explosive molecules like RDX, HMX, TNT, PETN, and HNS. The values of the velocity of detonation for these molecules are found to be very close to each other. Further comparison of empirical mathematical formulations was carried out for four other explosive molecules of relatively recent origin (CL-20, FOX-7, TATB and NTO). These molecules were selected as they were unknown at the time of the proposed formulations except that by Keshavarz (2006). For CL-20, the velocity of detonation by different methods is 9345.1 m/s (Kamlet), 9378.8 m/s (Rothstein), 9116.0 m/s (Xiong), 9383.7 m/s (Stein) and 9887.9 m/s (Keshavarz) respectively. The method proposed by Keshavarz gives a higher value of the velocity of detonation than the others. For FOX-7, the values are 8636.6 m/s (Kamlet), 8733.3 m/s (Rothstein), 8766.1 m/s (Xiong), 8645.0 m/s (Stein) and 8245.3 m/s (Keshavarz) respectively. In this case the Keshavarz approach gives a lower value of the velocity of detonation. For these molecules, the results by the Xiong method is very close to that obtained by the Kamlet method. Deviation, as well as dispersion of the calculated values by other methods, is on the high side.