The flow of stable detonation is determined mainly by the efficiency of the activation processes of chemical reactions
at the moment when the released energy is transferred to the adjacent to the detonation wave front layers of not yet decomposed explosive material, if
this efficiency is too low, the detonation front will
move forward with decreasing velocity, and will eventually become a sound wave. And it depends on the nature of the substance or mixture. You will
never squeeze more than 400-500 m/s out of black powder, but you will easily get about 3000-3500 m/s on a similar coal dynamo in a strong thick case
of large diameter and optimum density. In black powder, the shock (detonation) wave from the detonator primer will quickly turn into convective
combustion (combustion where heat transfer processes are carried out by penetration of hot gases between the mixture particles). If black powder is
simply set on fire, then detonation will not be possible in principle.
Well obviously mixed substances, where the combustible and oxidizing components are separated, will give a less fast shockwave in the end than organic
molecules or homogeneous mixtures. |