Patent attributes
An acoustic resonance igniter uses gas expanding through a nozzle to form a sonic, or under-expanded supersonic, jet directed against the opening of a blind resonance cavity in a central body, setting up a high-frequency sonic resonance which heats the gas within the cavity. A pintle extends coaxially with the nozzle and injects liquid propellant into the jet. The liquid propellant ignites with the heated gas within the resonance cavity forming combustion gases. The combustion gases flow through openings in a flange which supports the resonance cavity into a combustion chamber in the same direction as the gas jet flows. The liquid propellant is injected from within the support flange in the direction of combustion gas flow to film cool the combustion chamber wall and the flange and the central body supported by the flange. The acoustic resonance igniter may form a rocket engine ignition torch or a RCS thruster.