A flow control actuator includes a first side wall, a second side wall opposite and substantially parallel to the first side wall, an upstream wall mechanically coupled to upstream ends of the first and second side walls, and a downstream cap mechanically coupled to downstream ends of the first and second side walls. The first side wall, the second side wall, the upstream wall and the downstream cap collectively define an interior of the flow control actuator. An energy source is disposed in at least one of the first sidewall and the second sidewall. At least one fuel injector is disposed in the upstream wall, the first sidewall and/or the second sidewall for dispersing fuel into the flow control actuator. At least one air inlet is disposed in the upstream wall, the first sidewall and/or the second sidewall for introducing air into the flow control actuator. Fuel from fuel injector and air from the air inlet are ignited in the flow control actuator.

A flow control actuator includes a first side wall, a second side wall opposite and substantially parallel to the first side wall, an upstream wall mechanically coupled to upstream ends of the first and second side walls, and a downstream cap mechanically coupled to downstream ends of the first and second side walls. The first side wall, the second side wall, the upstream wall and the downstream cap collectively define an interior of the flow control actuator. An energy source is disposed in at least one of the first sidewall and the second sidewall. At least one fuel injector is disposed in the upstream wall, the first sidewall and/or the second sidewall for dispersing fuel into the flow control actuator. At least one air inlet is disposed in the upstream wall, the first sidewall and/or the second sidewall for introducing air into the flow control actuator. Fuel from fuel injector and air from the air inlet are ignited in the flow control actuator.

An apparatus is provided for an aircraft propulsion system. This apparatus includes an exhaust nozzle. The exhaust nozzle includes a flowpath, a passage, an outer door, an inner door and an actuator configured to move the outer door and the inner door between an open arrangement and a closed arrangement. The flowpath extends axially along a centerline through the exhaust nozzle. The passage extends laterally into the exhaust nozzle to the flowpath when the outer door and the inner door are in the open arrangement. The outer door is configured to pivot inwards towards the centerline when the outer door moves from the closed arrangement to the open arrangement. The inner door is configured to pivot outwards away from the centerline when the inner door moves from the closed arrangement to the open arrangement.

A propulsion system coupled to a vehicle. The system includes a diffusing structure and a conduit portion configured to introduce to the diffusing structure through a passage a primary fluid produced by the vehicle. The passage is defined by a wall, and the diffusing structure comprises a terminal end configured to provide egress from the system for the introduced primary fluid. A constricting element is disposed adjacent the wall. An actuating apparatus is coupled to the constricting element and is configured to urge the constricting element toward the wall, thereby reducing the cross-sectional area of the passage.

A propulsion system coupled to a vehicle. The system includes a diffusing structure and a conduit portion configured to introduce to the diffusing structure through a passage a primary fluid produced by the vehicle. The passage is defined by a wall, and the diffusing structure comprises a terminal end configured to provide egress from the system for the introduced primary fluid. A constricting element is disposed adjacent the wall. An actuating apparatus is coupled to the constricting element and is configured to urge the constricting element toward the wall, thereby reducing the cross-sectional area of the passage.

An annular exhaust nozzle is disclosed designed to accept and redirect jet engine exhaust thereby generating direct reactive thrust as well as thrust via induction.

A mixing tube with multiple shapes is provided, allowing additional injection of gas in order to keep the flow detached from the second shape in an ascent phase and to bring about, in a descent phase, a controlled detachment as a result of the change of slope between the two shapes. A propulsion nozzle for an engine of a spacecraft or aircraft is provided including such a mixing tube and a method for controlling the speed transition of the propulsion gases in such a nozzle in accordance with the altitude. Also, a method is provided for vectorising the thrust in such a nozzle by radial and asymmetrical injection of gas and a control method which prevents re-attachment of the jet to the second shape of such a propulsion nozzle for an engine of a spacecraft when it is in the take-off or landing phase.

An exhaust plume cooling device for cooling an exhaust gas plume to reduce deleterious heat effects on impinged and surrounding surfaces. The device is supportable in a position downstream of an exhaust nozzle of an exhaust gas plume-producing engine and configured to periodically interrupt the flow of exhaust gases by injecting fluid into the exhaust plume zone.

An exhaust plume cooling device for cooling an exhaust gas plume to reduce deleterious heat effects on impinged and surrounding surfaces. The device is supportable in a position downstream of an exhaust nozzle of an exhaust gas plume-producing engine and configured to periodically interrupt the flow of exhaust gases by injecting fluid into the exhaust plume zone.

A method of producing a pulsatile jet flow from a substantially constant flow primary jet in a way that is mechanically efficient, easy to implement, and allows direct control over pulse duration and pulsing frequency is disclosed herein. The invention includes at least two components: (a) a constant flow fluid jet produced by any normal method (e.g., propeller) that can be directionally vectored fluidically, mechanically, or electromagnetically and (b) a nozzle with multiple outlets (orifices) through which the vectored jet may be directed. By alternately vectoring the jet through different outlets, a transient (pulsatile) flow at an outlet is obtained even with a substantially constant primary jet flow. Additionally, the nozzle outlets may be oriented in different directions to provide thrust vectoring, making the invention useful for maneuvering, directional control, etc.