Effective use of overdriven detonation in high explosives

Abstract

Explosives can easily generate the high energy and the ultra-high pressure. The performance of explosive depends on its own chemical property, the detonation wave usually propagates with the stable value of pressure behind it, the pressure is so called "Chapman-Jouguet (C-J) pressure" . If the higher pressure over C-J pressure can be expected to occur, it is very effective for a development of new materials. We take notice of Overdriven Detonation (following ODD.) phenomenon that expects to bring out higher detonation pressures than C-J pressure of explosive. This phenomenon can be occurred when the flyer plate of high velocity impacts the explosive, or the explosive compressed by the advance detonates, or converging detonation of the explosive.

Euler–Lagrange simulation of high pressure shock waves

“…The shock wave arrival times of the two elements considered in the acceptor explosive are respectively: t 1 = 6.2678 µs, t 2 = 7.8247 µs, and the detonation velocity is: V d = 0.96 cm/µs. Table 2 results are close to experimental results obtained by Otsuka et al [6] and show that the detonation speed in overdriven detonation can exceed the Chapman-Jouguet speed. …”

“…in which the detonation velocity is higher than the Chapman-Jouguet velocity. Otsuka et al [6] have realized an experimental study of O.D.D. phenomenon.…”

“…While the shock wave travels in the donor at a speed limited by the Chapman-Jouguet (C-J) conditions, the high velocity impact of the plate against the acceptor creates a shock wave with speed much higher than the C-J detonation. Experimental results of this approach are carried out by Otsuka et al [6].…”

Detonation Wave Propagation in Double‐layer Cylindrical High Explosive Charges

“…Numerical studies of overdriven detonations by Mach reflections of detonation waves were also carried out. Otsuka et al [8], Itoh [9], and Hamada et al [10] used a manganin gauge and optical fibers to measure the detonation velocity and pressure at overdriven detonation of double cylindrical HE charges. A pressure four times higher than the normal detonation pressure (the Chapman-Jouguet (CJ) pressure) was obtained in their studies.…”