Efficient initiation of detonation waves is the key to the pulse detonation engine(AB.PDE) operation.In the process of deflagration to detonation transition(AB.DDT)

detonation waves were successfully triggered by controlling the shock wave reflection.Interaction between flame and shock is strengthened by putting obstacles in detonation chamber with reasonable arrangement

which can efficiently organize reflection of shock wave and initiate detonation timely.Thus

DDT distance was shortened comparatively.Gasoline/Air detonation waves propagate successfully in the combustor.These results are valuable to the investigation on DDT process of two-phase pulse detonation engine at high frequency.