Numerical study of detonation wave propagation in a confined supersonic flow

The dynamics of detonation waves propagating in a confined supersonic flow is numerically investigated to understand the effects of incoming flow velocity in a combustion chamber on detonation properties and structure. The computational code is based on the Euler equations with detailed chemistry. The detonation is directly initiated with high pressure and temperature at a given region inside a straight tube and then propagates both upstream and downstream. The study shows that as the incoming flow velocity increases, the properties of the detonation wave moving upstream and downstream are significantly changed. This leads to an increase or decrease in the velocity and strength of the detonation wave, and a change in smoked foil cellular pattern. It was found that the strength of the upstream-moving detonation becomes higher and the propagation velocity decreases as the incoming velocity increases. These factors result in a change of the smoked foil pattern such as the cell length, width, and track angle. Moreover, the time in stabilizing the detonations moving in opposite directions is significantly changed with a supersonic incoming flow. An initiation delay occurs on the downstream-moving detonation since it is weakened in a supersonic flow.