Ignition method effect on detonation initiation characteristics in a pulse detonation engine

The detonation initiation performance of a kerosene fueled air-breathing pulse detonation engine was investigated. Three ignition methods were investigated experimentally, including spark ignition, hot jet, and pre-detonator. The deflagration-to-detonation transition distance measured using the hot jet initiation method was 1130 mm, a reduction of approximately 150 mm compared to the baseline spark ignition method. As the length of jet pipe decreased to 100 mm, the detonation frequency increased to 35 Hz. The PDE operating frequency had little impact on detonation initiation time when pre-detonator ignition method was used, and there was a slight deviation error of detonation initiation time at each of the operating frequencies. However, when spark and hot jet ignition methods were used, detonation initiation time decreased at the increased operating frequency and the deviation error of detonation initiation time was much higher. The shortest detonation initiation time of 2-3 ms and deflagration-to-detonation transition distance of 700 mm were obtained using the pre-detonator ignition method.