ABSTRACT
The main interest in this chapter is the external effect of a chemical explosive, which, upon detonation, is almost immediately converted into a hot and highly pressurized gas. The gas expands violently pushing the air in front of it. As the speed of expansion (outow speed) far exceeds the sonic velocity of air, a shock wave (a blast wave) forms, traveling with the expanding surface of the gas volume. The pressure inside the gas decreases during the expansion, but even when it drops below the atmospheric pressure, the expansion still continues due to inertia, later stopping and possibly reversing the direction of movement. During an early phase of explosion, the blast wave separates from the explosive gas, and continues independently, becoming gradually slower and weaker.
