The distributions of detonation parameters in detonation chamber were gained by analytical numeration
and then multiple-cycle numerical simulations were carried out after detonation wave broke up to shock wave.The analysis on the mechanism of unsteady ejection shows that the process of unsteady ejection can be divided to four stages
and the ejection performance of annular pulse detonation duct is stronger than round pulse detonation duct.Different structures and parameters could induce different time-averaged thrust augmentations.The better shape of the ejector inlet
interior surface
ejector length-to-diameter ratio and axial placement were obtained through analysis
offering references to augment the performance of pulse detonation engine.