Abstract: Disclosed is a method for initiating startup of a rocket engine configured to run on a liquid fuel and liquid hydrogen peroxide, including the steps of: initially decomposing the liquid hydrogen peroxide by passing the liquid hydrogen peroxide through a catalyst bed; passing decomposition products from the catalyst bed to a reaction chamber of the rocket engine and mixing the decomposition products with the liquid fuel to initiate detonation. Once detonation is initiated, the liquid H2O2 and liquid fuel are passed directly to a reaction chamber of the rocket, bypassing the catalyst bed. A rocket system includes a rocket engine having an initial ignition circuit having a catalyst bed sized to support decomposition of liquid H2O2 for initial reaction with the liquid fuel. The rocket engine, upon initial ignition, is configured to run on liquid fuel and liquid H2O2 without first passing the liquid H2O2 through the catalyst bed.

Abstract: A rotating detonation combustor includes a nozzle coupled to the combustor body at or near the exhaust opening to choke the exhaust opening. A rotating detonation combustor may include a diverting plate positioned radially inward of the inlet annulus and inlet channels for diverting flow of a mixture in an axial direction. A rotating detonation combustor may include a combustor body including an outer shell at least partially defining a detonation combustion chamber and extending axially from a base toward an exhaust opening of the detonation combustion chamber. The base defines a passageway in fluid communication with the detonation combustion chamber and includes an inlet annulus for axially directing a second fluid into the passageway and a plurality of inlet channels for radially directing a third fluid into at least one of the passageway or the detonation combustion chamber, and the detonation combustion chamber is free of any inner body.

Abstract: A solid fuel propulsion system includes a housing, an air inlet configured to enable air to flow into the housing, an air duct, a rotation detonation chamber, and a nozzle assembly. The air duct is disposed in the housing and is in fluid communication with the air inlet. The air duct is configured to supply air for combustion of a solid fuel configured to sublimate into a gaseous fuel mixture. The rotation detonation chamber is disposed in the housing aft of the air duct and is configured to combust the gaseous fuel mixture and air to generate a rotating detonation wave. The nozzle assembly is configured to expand and exhaust the flow prompted by the rotating detonation wave to generate thrust.

Abstract: A combustion system includes an annular tube disposed between an inner wall and an outer wall, the annular tube extending from an inlet end to an outlet end; at least one annulus inlet disposed in the annular tube proximate the inlet end, the annulus inlet providing a conduit through which fluid flows into the annular tube; at least one outlet disposed in the annular tube proximate the outlet end; at least one inlet fluid plenum disposed upstream of the annulus inlet; and at least one fluid inlet disposed upstream of the inlet fluid plenum. The fluid inlet is linearly offset from the annulus inlet.

Abstract: A combustion system includes an annular tube disposed between an inner wall and an outer wall, the annular tube extending from an inlet end to an outlet end; at least one fluid inlet disposed in the annular tube proximate the inlet end, the fluid inlet providing a conduit through which fluid flows into the annular tube; at least one outlet disposed in the annular tube proximate the outlet end; at least one primary fuel injector, the primary fuel injector dispersing fuel into a fluid stream entering the annular tube via the fluid inlet; and at least one secondary fuel injector, the secondary fuel injector disposed in the annular tube.

Abstract: The invention relates to a ramjet including a detonation chamber and an aircraft comprising such a ramjet. According to the invention, the ramjet (S1) comprises an annular detonation chamber (2) having a continuous detonation wave and fuel injection means (6) for continuously injecting fuel (F2) directly into the chamber (2) just downstream of an air injection base (3). The fuel (F2) and the air (F1) are injected separately into the detonation chamber (2) in a permanent manner throughout the operation of the ramjet (S1).

Abstract: A method for determining the optimum inlet geometry of a liquid rocket engine swirl injector includes obtaining a throttleable level phase value, volume flow rate, chamber pressure, liquid propellant density, inlet injector pressure, desired target spray angle and desired target optimum delta pressure value between an inlet and a chamber for a plurality of engine stages. The method calculates the tangential inlet area for each throttleable stage. The method also uses correlation between the tangential inlet areas and delta pressure values to calculate the spring displacement and variable inlet geometry of a liquid rocket engine swirl injector.

Abstract: A method for determining the optimum inlet geometry of a liquid rocket engine swirl injector includes obtaining a throttleable level phase value, volume flow rate, chamber pressure, liquid propellant density, inlet injector pressure, desired target spray angle and desired target optimum delta pressure value between an inlet and a chamber for a plurality of engine stages. The tangential inlet area for each throttleable stage is calculated. The correlation between the tangential inlet areas and delta pressure values is used to calculate the spring displacement and variable inlet geometry. An injector designed using the method includes a plurality of geometrically calculated tangential inlets in an injection tube; an injection tube cap with a plurality of inlet slots slidably engages the injection tube. A pressure differential across the injector element causes the cap to slide along the injection tube and variably align the inlet slots with the tangential inlets.

Abstract: A catalyst free method of igniting an ionic liquid is provided. The method can include mixing a liquid hypergol with a HAN-based ionic liquid to ignite the HAN-based ionic liquid in the absence of a catalyst. The HAN-based ionic liquid and the liquid hypergol can be injected into a combustion chamber. The HAN-based ionic liquid and the liquid hypergol can impinge upon a stagnation plate positioned at top portion of the combustion chamber.

Abstract: An igniter for a rocket engine or motor comprising a combustion chamber with a solid fuel, an inlet for supplying an oxidizer to the combustion chamber to ignite the solid fuel and an outlet for discharging exhaust gas, wherein the igniter is arranged to discharge exhaust gas to the rocket engine for igniting the rocket engine. The igniter can be used for multiple ignitions and can also be re-used after re-filling.

Abstract: A bi-propellant injector (66) includes a first injector element (68) and a second injector element (70) injecting a first propellant (69) and a second propellant (71), respectively, into a combustion chamber (53). A flame-holding zone igniter (74) is adjacent to and ignites recirculation of at least a portion of the first propellant (69) and at least a portion of the second propellant (71) within a flame-holding zone (76).

Abstract: The invention is directed to an electrical ignitor for a model rocket, including two insulated lead wires, with each lead wire having an uninsulated end. An element wire interconnects the uninsulated ends from each lead wire. The element wire forms a plurality of turns around one of the insulated lead wires. A pyrogen compound surrounds the element wire.

Abstract: The multifuel combustion engine is a Lenoir cycle (constant volume), pulst combustion engine capable of operating on gasoline, diesel or kerosene based fuels. Although the preferred embodiment is described in terms of Lenoir cycle pulsejet engines, the present invention has application to combustion engines in general. The conventional Lenoir cycle engine has been modified to provide a direct, premixed fuel-air spray to the combustion chamber and means for igniting the fuel-air spray. Said fuel-air spray is separate and distinct from the fuel-air charge which is fed to the combustion chamber from the engine head. Additionally, means are provided for preheating the combustion chamber so that the same fuel-air ratio mixes can be fed to the combustion chamber for cold start or hot restart of the engine. A method of burning different fuels in combustion engines is also claimed. The present invention includes the application of the modified Lenoir cycle engines to smoke generator equipment.

Abstract: The utilization of metal hydride and an acidic reagent for the accelerating of masses, and propulsion devices for applying such materials. The materials are of a saline complex metal hydride and acidic reagent which is sprayed onto the metal hydride which is offered in a lumpy consistency, for the pulse-like generation of expanding reaction gas bubbles in a constructive or dynamically, yieldably dammed chamber. Also provided is a propulsion device for the application of the above materials, with a support for a saline complex metal hydride of a lumpy consistency in a yieldably dammed expansion chamber in which an injection nozzle for the reagent is directed towards a surface portion of the metal hydride.