A pulse combustor system for operating pulse combustors in anti-phase. The pulse combustor system includes two pulse combustors connected at their combustion chambers by a connecting tube. Each of the pulse combustors has a fundamental oscillation mode and one or more additional oscillation modes when operated in isolation. The connecting tube has a length corresponding to ¼ of the fundamental oscillation mode wavelength.

A system and method is disclosed for the start-up and control of pulsejet engines and this system includes an Electronic Fuel Injection (“EFI”) system that further includes one or more electrically controlled fuel injectors that can be selectively operated for start-up and control of such pulsejet engines. According to the system and method, the rate and/or pattern of fuel delivery to pulsejet engines can be varied not only by controlling the amount of time the fuel injectors are open versus closed to define a “duty cycle,” but also with the capability to selectively disable one or more fuel injectors in the programmed manner for start-up and control of such pulsejet engines.

A system and method is disclosed for the start-up and control of pulsejet engines and this system includes an Electronic Fuel Injection (“EFI”) system that further includes one or more electrically controlled fuel injectors that can be selectively operated for start-up and control of such pulsejet engines. According to the system and method, the rate and/or pattern of fuel delivery to pulsejet engines can be varied not only by controlling the amount of time the fuel injectors are open versus closed to define a “duty cycle,” but also with the capability to selectively disable one or more fuel injectors in the programmed manner for start-up and control of such pulsejet engines.

Embodiments are directed toward a monopropellant continuous detonation engine. In some embodiments, the continuous detonation engine includes an engine body, a monopropellant feed assembly, and a detonation initiator. The engine body defines a detonation wave channel. The monopropellant feed assembly delivers monopropellant from a monopropellant storage tank into the detonation wave channel. The detonation initiator initiates continuous detonation of the monopropellant in the detonation wave channel, preferably without a catalyst to promote decomposition of the monopropellant. Accordingly, specific impulse is increased compared to constant-pressure reaction thrusters that catalytically decompose the monopropellant with deflagration combustion.

A detonation engine includes at least one chamber wall and a first detonation chamber defined by the at least one chamber wall, the first detonation chamber having a first end and a second end. The first detonation chamber is linear, curved, or includes a plurality of detonation chamber segments that are linear and/or curved, and the detonation engine is configured such that detonation repeatedly propagates from the first end of the first detonation chamber to the second end of the first detonation chamber.

A detonation engine includes at least one chamber wall and a first detonation chamber defined by the at least one chamber wall, the first detonation chamber having a first end and a second end. The first detonation chamber is linear, curved, or includes a plurality of detonation chamber segments that are linear and/or curved, and the detonation engine is configured such that detonation repeatedly propagates from the first end of the first detonation chamber to the second end of the first detonation chamber.

A system and method for ram air intake for pulse combustion systems is disclosed that improves the ability of pulse combustions to ingest air into the inlet pipe when the pulse combustion system is moving in a direction opposite the direction the open end of the inlet pipe is facing and the system and method includes the ability to increase the thrust output from the pulse combustion system.

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 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 rotating detonation engine can include an annular combustion chamber, a fuel feed line, an oxidizer feed line, one or more igniters configured to detonate fuel and oxidizer reactants, a nozzle proximate the outlet of the annular combustion chamber, and a pre-detonation tube configured to provide the fuel and oxidizer reactants fed from the fuel feed line and the oxidizer feed line to the one or more detonators. The pre-detonation tube can have an outer surface, an inner surface, an inner diameter defining an internal flow region, an inlet proximate the fuel feed line and oxidizer feed line, and an outlet proximate the annular combustion chamber, and can defines a radial geometry that curves around the exterior of the annular combustion chamber.