Generation of high pressures during the shock-flame interaction

The interaction of a flame with shock waves generated byexternal sources is investigated using numerical simulation methods. It is shown that the effect of shock waves with various intensities on the combustion front in a closed volume (channel) leads to qualitatively different scenarios of the further development of combustion. Situations when the process development results in the generation of sufficiently high pressures, which exceed many times the pressures in the incident shock wave, are singled out individually. In this case, maximum high pressures occur as a result of the deflagration-to-detonation transition (DDT). The detailed analysis of the dynamics of TCD DDT, which is developed by various scenarios, showed that the most general mechanism of the transition is the localization of the pressure peak in the reaction zone. The well-known scenario of transition to detonation by the mechanism of the formation of “hot spots” ahead of the flame is observed in a relatively narrow range of initial conditions. The development of detonation in such a mode leads to generation of still higher pressures, which exceed the pressure in DDT, and the probability of the realization of this scenario rises with the decrease of mixtures reactivity.