Rotating detonation engines are provided with various improvements pertaining to performance and reliability. Improvements pertain to, for example, a fluidic valve/premixing chamber, injection/swirl, flow control and turning, ignition, and cooling. A rotating detonation engine can include a cylindrical inner shell within an outer housing, a cylindrical outer shell positioned between the inner shell and the outer housing, an annular gap between the outer shell and the outer housing functioning as a detonation chamber.

An engine that uses detonation for generating energy includes a housing; an inlet configured to inject a fuel mixture into an ignition region of the housing, the inlet being attached to the housing; an ignitor located in the ignition region and configured to ignite the fuel mixture; a deflagration to detonation, DDT, region in fluid communication and downstream from the ignition region; a pair of electrodes located in the DDT region and configured to apply nanosecond repetitive voltage pulses to the DDT region; and a detonation region, within the housing, in fluid communication and downstream from the DDT region. The nanosecond repetitive voltage pulses generate a non-thermal plasma that transition a combustion front propagation through the housing from a deflagration mode to a detonation mode.

A rotating detonation engine (RDE) is disclosed which includes a housing, an injector assembly disposed within the housing, the injector assembly includes a fuel manifold, an oxidizer manifold, and a combustion chamber, fuel from the fuel manifold and an oxidizer from the oxidizer manifold are combined and combusted in the combustion chamber, each of the fuel and oxidizer manifolds communicates with the combustion chamber via a plurality of Tesla valves each via a corresponding port, wherein the plurality of Tesla valves substantially eliminate reverse flow of exhaust gases from the combustion chamber back to the fuel manifold or the oxidizer manifold.

The invention relates to jet engines, in particular to pulse detonation jet engines. The required technical result, which consists in increasing the efficiency and reliability, is achieved in an engine with a combustion chamber which is structured as detonation resonator with an outlet to the exhaust nozzle. The resonator has form of an aspherical reflector symmetrical with respect to the engine axis. The engine uses gaseous fuels and gaseous oxidizer and single stage combustion process. In case of use of hydrocarbon fuel, the fuel conduit has a pyrolyzing chamber. Pyrolizing is achieved by contact of fuel flow with heated back side of said reflector. A mixture of fuel and oxidizer is supplied into the combustion chamber through an annular supersonic injection system. To initiate detonation, these engines may have a detonation initiator in the form of a tube plugged at the distal end and open at the end inserted into the combustion chamber and located along the axis of the engine. Detonation products ejected through the exhaust nozzle create thrust that pushes the engine in the opposite direction. This design of the pulse detonation jet engine is simple, reliable and allows achieving high efficiency of generation of thrust propulsion force thanks to maintaining cyclic resonant detonation at a frequency of around 10 kHz.

The invention relates to jet engines, in particular to pulse detonation jet engines. The required technical result, which consists in increasing the efficiency and reliability, is achieved in an engine with a combustion chamber which is structured as detonation resonator with an outlet to the exhaust nozzle. The resonator has form of an aspherical reflector symmetrical with respect to the engine axis. The engine uses gaseous fuels and gaseous oxidizer and single stage combustion process. In case of use of hydrocarbon fuel, the fuel conduit has a pyrolyzing chamber. Pyrolizing is achieved by contact of fuel flow with heated back side of said reflector. A mixture of fuel and oxidizer is supplied into the combustion chamber through an annular supersonic injection system. To initiate detonation, these engines may have a detonation initiator in the form of a tube plugged at the distal end and open at the end inserted into the combustion chamber and located along the axis of the engine. Detonation products ejected through the exhaust nozzle create thrust that pushes the engine in the opposite direction. This design of the pulse detonation jet engine is simple, reliable and allows achieving high efficiency of generation of thrust propulsion force thanks to maintaining cyclic resonant detonation at a frequency of around 10 kHz.

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 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.

Rotating detonation engines are provided with various improvements pertaining to performance and reliability. Improvements pertain to, for example, a fluidic valve/premixing chamber, injection/swirl, flow control and turning, ignition, and cooling.