A pulsed detonation engine may include a detonation tube for receiving fuel and an oxidizer to be detonated therein, one or more fuel-oxidizer injectors for injecting the fuel and oxidizer into the detonation tube, one or more purge air injectors for injecting purge air into the detonation tube for purging the detonation tube, and an ignition for igniting the fuel and oxidizer in the detonation tube so as to initiate detonation thereof. The detonation tube has an upstream end, a downstream end, and an axially extended portion extending from the upstream end to the downstream end and having a perimeter. The fuel-oxidizer injectors and purge air injectors may be disposed at least along the axially extended portion. The ignition may include a plurality of igniters disposed at or near the perimeter of the axially extended portion, spaced about the perimeter, at or near the upstream end of the detonation tube.

An accessory power unit assembly includes a combustor assembly that includes a pulse detonation tube that defines a curved passage between an inlet that receives a compressed airflow and a discharge end. The detonation tube operates as a resonant cavity to sustain a standing pressure wave. Fuel injected into the pulse detonation tube is timed to coincide with movement of a standing wave toward a discharge end. The standing wave provides an increase in pressure of an output exhaust gas driving the turbine without a corresponding increase in load.

A wave disc engine apparatus is provided. A further aspect employs a constricted nozzle in a wave rotor channel. A further aspect provides a sharp bend between an inlet and an outlet in a fluid pathway of a wave rotor, with the bend being spaced away from a peripheral edge of the wave rotor. A radial wave rotor for generating electricity in an automotive vehicle is disclosed in yet another aspect.

A wave disc engine apparatus is provided. A further aspect employs a constricted nozzle in a wave rotor channel. A further aspect provides a sharp bend between an inlet and an outlet in a fluid pathway of a wave rotor, with the bend being spaced away from a peripheral edge of the wave rotor. A radial wave rotor for generating electricity in an automotive vehicle is disclosed in yet another aspect.

A pulse combustor system for efficiently operating a pulse combustor. The pulse combustor system includes the pulse combustor and a duct. The pulse combustor has a combustion chamber defining an internal space, a conduit having a first end in fluid communication with the internal space and a second end in fluid communication with an environment outside of the pulse combustor system, and a fuel injector configured to inject fuel into the internal space of the combustion chamber. The duct has two openings, with one opening disposed adjacent to the second end of the conduit. The pulse combustor system has an average operating frequency, and the duct has a length that is about one quarter of a wavelength corresponding to the average operating frequency. The pulse combustor and the duct each has a central longitudinal axis, and the two axes are substantially aligned.

A compressor assembly for a pulsejet engine. The pulsejet engine including a burner positioned within a combustion chamber of the pulsejet engine. The compressor assembly includes a compressor coupled in fluid communication with the combustion chamber. The compressor is adapted to intake a first volume of air and to release a volume of compressed air. The burner is configured to receive the volume of compressed air and release a volume of a burned compressed air and fuel mixture. An active valve is operatively coupled between the compressor and the combustion chamber. The active valve is adapted to control entry of the volume of compressed air into a first end of the burner. A standing wave is formed inside the compressor to compress the first volume of air during operation of the pulsejet engine.

A compressor assembly for a pulsejet engine. The pulsejet engine including a burner positioned within a combustion chamber of the pulsejet engine. The compressor assembly includes a compressor coupled in fluid communication with the combustion chamber. The compressor is adapted to intake a first volume of air and to release a volume of compressed air. The burner is configured to receive the volume of compressed air and release a volume of a burned compressed air and fuel mixture. An active valve is operatively coupled between the compressor and the combustion chamber. The active valve is adapted to control entry of the volume of compressed air into a first end of the burner. A standing wave is formed inside the compressor to compress the first volume of air during operation of the pulsejet engine.

A pulse combustor system for reducing noise and/or vibration levels. The system includes a pulse combustor including a combustion chamber, an inlet pipe, an exhaust pipe, and a first fuel injector for injecting fuel into the combustion chamber. The pulse combustor has a fundamental oscillation mode and one or more additional oscillation modes. The system includes at least one pressure sensor for measuring a pressure inside the fuel combustor and/or a at least one fluid velocity sensor for measuring fluid velocity at the inlet pipe or at the exhaust pipe. A controller adjusts a rate of fuel supply to the pulse combustor if the measured pressure and/or the measured velocity is above a predetermined threshold value to reduce excitation of the one or more additional oscillation modes.

A pulse combustor system for reducing noise and/or vibration levels. The system includes a pulse combustor including a combustion chamber, an inlet pipe, an exhaust pipe, and a first fuel injector for injecting fuel into the combustion chamber. The pulse combustor has a fundamental oscillation mode and one or more additional oscillation modes. The system includes at least one pressure sensor for measuring a pressure inside the fuel combustor and/or a at least one fluid velocity sensor for measuring fluid velocity at the inlet pipe or at the exhaust pipe. A controller adjusts a rate of fuel supply to the pulse combustor if the measured pressure and/or the measured velocity is above a predetermined threshold value to reduce excitation of the one or more additional oscillation modes.

The present disclosure is directed to a supersonic oblique rotating detonation wave engine (SORDE) and systems and methods for generating a supersonic oblique rotating detonation wave. The SORDE is configured to produce and sustain a supersonic oblique rotating detonation wave through the injection of fuel at supersonic speeds into an inlet air flow between Mach 1 and Mach 7. The SORDE and method include injecting fuel into the inlet air in an amount to generate an equivalence ratio of 0.2 to 2.5. Some embodiments include a plurality of fuel injector ports each having a diameter of about 0.010 inches to about 0.040 inches; an annular wedge disposed in or upstream of the detonation chamber with an angle of about 5 degrees to about 40 degrees relative to a longitudinal axis of the engine; and/or a cylindrical center body disposed in or upstream of the detonation chamber.