Explosive velocity
Explosive velocity, also known as detonation velocity or velocity of detonation (VoD), is the velocity at which the shock wave front travels through a detonated explosive. The data listed for a specific substance is usually a rough prediction based upon gas behavior theory[citation needed] (see Chapman-Jouguet condition), as in practice it is difficult to measure[citation needed]. Explosive velocities are always faster than the local speed of sound in the material.
If the explosive is confined before detonation, such as in an artillery shell, the force produced is focused on a much smaller area, and the pressure is massively intensified. This results in explosive velocity that is higher than if the explosive had been detonated in open air. Unconfined velocities are often approximately 70 to 80 percent of confined velocities.[1]
Explosive velocity is increased with smaller particle size (i.e. increased spatial density), increased charge diameter, and increased confinement (i.e. higher pressure).[1]
Typical detonation velocities in gases range from 1800 m/s to 3000 m/s. Typical velocities in solid explosives often range beyond 4000 m/s to 10300 m/s.