An experimental study of the ignition and burning mechanisms in a pulse combustor (Combustion characteristics supplied with a propane-air mixture)

Abstract

The ignition and burning mechanisms of pulse combustion are experimentally investigated using a basic two-dimensional combustor supplied with a propane-air mixture. The forced mixture supply widens the pulsation limit to a practically usable one. the burning process is so rapid that there exists no flame in the combustor at the time of the mixture inflow in the next combustion cycle. The back-flow from the tail-pipe also contains no flame. Then the ignition of the mixture is found to be caused by a direct contact and rapid mixing with residual hot burned gases, which can be regarded as a spontaneous ignition. High-speed schlieren movies reveal that a pair of large scale eddy motions, formed by the in flowing mixture jet, promote reveal that a pair of large scale eddy motions, formed by the inflow mixture jet, promote the mixing of the mixture and hot nurned gases, resulting in a distributed reaction zone.