Ignition of Organic Explosive Materials by a Copper Oxide Film Absorbing a Laser Pulse

Abstract

This work present experimental results of PETN ignition and of numerical simulations of PETN, RDX, HMX, and TATB ignition by a copper oxide (CuO) film heated using a millisecond fiber laser YLS‐150. It was established that the dynamic ignition threshold of organic explosive materials (EM) in a three‐layer system (glass – CuO – EM) by a laser pulse has a minimum at the CuO film thickness of 12 μm . The density of the critical ignition energy of EM is increasing in the sequence of PETN, RDX, HMX, and TATB with PETN having the smallest and TATB having the highest density of the critical ignition energy.

Effect of Decomposition of CuO Film on Ignition of Organic Explosives by a Laser Pulse

“…For example, for PETN at T s ¼ 590:0 K calculation by (21) gives z r � 2:6 mm, which is much less than the area of pre-explosion heating of EM (Figure 1) and is close to the results of numerical calculation (Figure 4). Figure 5 shows the results of experiments [20] on PETN ignition by an ytterbium fiber laser in a three-layer system…”

“…Numerical calculations of the PETN dynamic ignition delay time for a three-layer system are consistent with the experiment with a CuO film thickness of about 9.0 μm [20,21]. In [21], in order to better describe the experiment on the dependence of the PETN dynamic ignition time on the thickness of the CuO film, it was proposed to take into account the endothermic reaction of the thermal decomposition of the CuO film. In this work, the endothermic effect was evaluated during the decomposition of copper oxide:…”

“…At the same time, the three-layer system glass -CuO -EM was presented in the form of a continuous medium, in which thermophysical, optical, and chemical properties depend on the coordinate. Arrhenius nonlinearity in the difference schemes for thermal conductivity equations (3) and (5) was linearized at each time step by the Frank-Kamenetsky transformation [21]:…”

“…According to (21), the width of the reaction layer depends exponentially on the E=T s relationship. The smaller the E=T s ratio, the smaller the width of the reaction layer, which is qualitatively consistent with the results of numerical simulation.…”

“…Experimental studies and numerical simulation of PETN ignition with a CuO film that absorbs a millisecond laser pulse are described in [19][20][21]. The CuO -PETN and the glass -CuO -PETN systems were considered.…”