Experiments were established on changing the oxidizer injection area to explore the rotating detonation wave(RDW)propagation characteristics effected by the area,and validate the working feasibility of successful igniting rotating detonation engine(RDE)in this condition. H_2 as fuel and air as oxidizer were separately injected into annular combustor through the slot-orifice injection configuration. The experimental results show RDE can steadily operate in a wider range of oxidizer injection area,and the bes...