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Deflagration-to-detonation transition of kerosene–air mixtures in a small-scale pulse detonation engine

An experimental study of flame propagation, acceleration, and transition to detonation in kerosene–air mixture in a small-scale pulse detonation engine (SPDE) was performed. An SPDE model with the aero-valve and two different obstacles in detonation tube was designed that the inner diameter and the overall length were 29 and 995 mm, respectively. The model was performed with kerosene as fuel under the condition of filling air by an airblower, and was ignited by a spark plug with low energy. The propagation of the flame and pressure waves was measured by pressure transducers and ion probes. The pairs of transducers and probes were placed at various locations along the tube in order to get information about the progress of the phenomena and the detonation wave properties were analysed when the SPDE was ignited at different frequency. As a result of the experiments, deflagration-to-detonation transition regimes and detonation parameters of kerosene–air mixture were determined. The current deflagration-to-detonation transition regimes observed in small-scale tubes is applicable to optimization and design of a small-scale propulsion system based on pulse detonation engines.