Abstract: Proposed is a hybrid rocket engine using an electric motor-driven oxidizer pump, the hybrid rocket engine including: an oxidizer tank configured to store the oxidizer; an oxidizer pump configured to pressurize the oxidizer by being connected to the oxidizer tank through a first oxidizer supply line; a drive unit including an electric motor configured to drive the oxidizer pump and a battery configured to supply power to the electric motor; an auxiliary oxidizer line configured to guide the oxidizer from the oxidizer tank to the electric motor to cool the electric motor; an oxidizer recirculation line configured to recharge oxidizer vapor, generated through heat exchange between the electric motor and the oxidizer, to the oxidizer tank, thereby pressurizing an inner side of the oxidizer tank; and a combustion chamber configured to combust the oxidizer and fuel by being connected to the oxidizer pump through a second oxidizer supply line.

Abstract: The fuel nozzle for the gas turbine includes a radial swirler and an axial swirler. The radial swirler is arranged to swirl a first flow of a first oxidant-fuel mixture and the axial swirler is arranged to swirl a second flow of a second oxidant-fuel mixture. The first flow may be fed by a central conduit and the second flow may be fed by an annular conduit surrounding the central conduit.

Abstract: An aircraft comprises a machine body. The machine body encloses a turbofan gas turbine engine and a plurality of ancillary systems. The turbofan gas turbine engine comprises, in axial flow sequence, a heat exchanger module, a fan assembly, a compressor module, a combustor module, a turbine module, and an exhaust module. The machine body comprises a single fluid inlet aperture, with the fluid inlet aperture being configured to allow a fluid cooling flow to enter the machine body and to pass through the heat exchanger module. The heat exchanger module is configured to transfer a waste heat load from the gas turbine engine and the ancillary systems to the fluid cooling flow prior to an entry of the entire fluid cooling flow into the fan module.

Abstract: Rocket propulsion systems and associated methods are disclosed. A representative system includes a combustion chamber having an inwardly-facing chamber wall enclosing a combustion zone. The chamber has a generally spherical shape and is exposed to the combustion zone. A propellant injector is coupled to the combustion chamber and has at least one fuel injector nozzle positioned to direct a flow of cooling fuel radially outwardly along the inwardly-facing chamber wall. In addition to or in lieu of the foregoing features, the injector can include an oxidizer piston and a fuel piston that deliver oxidizer and fuel, respectively, to the combustion chamber, in a sequenced manner so that the oxidizer is introduced prior to the fuel.

Abstract: A propulsion system for an aircraft includes a gas turbine engine and a fuel tank, wherein the fuel includes at least a proportion of a sustainable aviation fuel—SAF—having a density between 90% and 98% of the density, ?K, of kerosene and a calorific value between 101% and 105% the calorific value CVK, of kerosene. The engine includes a combustor; and a fuel pump arranged to supply a fuel thereto at an energy flow rate, C, the pump being arranged to output fuel at a volumetric flow rate, Q, the percentage of fuel passing through the pump not provided to the combustor being referred to as a spill percentage. The fuel include X % SAF, where X % is in the range from 5% to 100%, and has a density, ?F, and a calorific value CVF.

Abstract: An air intake system for an aircraft, which is switchable between a performance mode and a filtered mode, includes a duct forming filtered air inlet slits. The air intake system also includes interconnected gills adjacent to the filtered air inlet slits. The gills are movable between various gill positions including a closed position substantially covering the filtered air inlet slits and an open position substantially exposing the filtered air inlet slits. The air intake system also includes an actuator configured to move the gills into the closed position in the performance mode and the open position in the filtered mode.

Abstract: A passive flow splitting system for use in a turbine engine control system to provide split fuel flow to two fuel manifolds to supply primary and secondary fuel injectors for the particular combustion zones thereof utilizing intentionally different split ratios dependent on ascending or descending combustion fuel flow is provided. The system includes a passive fuel divider valve (FDV) that includes a primary piston and a secondary piston. The primary piston is moveable independently from the secondary piston during a portion of its stroke, and is hydro-locked to the secondary piston during another portion of its stroke. An ecology valve is also provided to purge the fuel from the primary and/or secondary manifolds during different modes of operation. A transfer valve is included to control the position of ecology piston of the ecology valve.

Abstract: Control of low pressure recoup air in a gas turbine engine disposed in a gas turbine enclosure with low pressure recoup air piping coupled to a gas turbine combustion exhaust and gas turbine engine enclosure is disclosed. A first valve of the piping controls a flow of the recoup air to the gas turbine combustion exhaust. A second valve of the piping diverts the recoup air to the enclosure for eventual flow to the air intake. A controller controls the flow of the recoup air from the piping to the exhaust and/or the enclosure as a function of ambient and air intake temperature measurements, and a predetermined temperature requirement having an ambient temperature constraint and an air intake temperature differential constraint.

Abstract: A method and system for controlling fuel flow to an aircraft engine during start are provided. Following light-off, an actual value of at least one engine operating parameter is obtained. Based on a difference between the actual value and a target value, a first command is generated to cause fuel flow to be provided to the engine's combustor according to a computed fuel flow rate defined by a fuel schedule of the engine. When the computed fuel flow rate is within a fuel flow rate limit, the first command is output. Otherwise, a limiting factor is applied to the computed fuel flow rate to limit a reduction in fuel flow to the combustor and a limited fuel flow rate is obtained, and a second command is output to cause fuel flow to be provided to the combustor according to the limited fuel flow rate.

Abstract: An aircraft turbine engine includes a gas generator and a fan arranged upstream of the gas generator and configured to generate a main gas flow, of which one portion flows in a stream from the gas generator to form a primary flow, and of which another portion flows in a stream around the gas generator to form a secondary flow. The gas generator includes a low pressure body having a rotor driving the fan by means of a crown of a mechanical planetary reduction gear. The turbine engine further includes an electrical machine mounted coaxially around the reduction gear and having a rotor rotated by the crown of the reduction gear, and a stator extending around the rotor of the electrical machine.

Abstract: A method for monitoring an aircraft turboshaft engine including a vibration sensor capable of outputting a vibration signal and a spark plug. The method includes, based on the vibration signal output by the vibration sensor, a step of determining a level of vibration of the turboshaft engine as well as a step of determining an indicator of spark plug wear.

Abstract: The gas turbine engine can have a pneumatic actuator; an intake device secured to a gas path wall delimiting the gas path, the intake device having a tubular body protruding from the gas path wall into the gas path and an inlet aperture formed in the tubular body, the inlet aperture spaced-apart from the gas path wall and facing downstream relative a flow orientation of the gas path, the intake device having an internal conduit extending from the inlet aperture, along the tubular body, to an outlet across the gas path wall; and a fluid line fluidly connecting the outlet of the intake device to the pneumatic actuator.

Abstract: Airframe integrated scramjet engines are disclosed. Scramjet engines within the scope of this disclosure may be configured to integrate smoothly with an airframe of a hypersonic flight aircraft or vehicle. The scramjet engine may include capture shape of an inlet configured to capture airflow, a combustor configured for combustion of fuel and air, and an exit shape of a nozzle configured for expansion of the combusted fuel and air to provide hypersonic thrust. In some embodiments, the scramjet engine has a fixed geometry and a transitioning cross-sectional shape over its full length. The scramjet engine is configured to be a component of launch vehicle system.

Abstract: An air-breathing rocket engine in certain embodiments comprises an outer shell and an interior portion situated entirely within the front end of the outer shell. The interior portion includes a funnel-shaped intake and an annular primary combustion chamber between the inner front wall of the shell and the outer surface of the funnel-shaped intake. The intake has a central aperture that is in fluid communication with the throat and exhaust areas within the outer shell. A second circumferential gap is formed between the outer surface of the front inner wall and the inner surface of the front end of the outer shell and is in fluid communication with the throat and exhaust areas within the outer shell. One or more injector ports and one or more ignition ports are situated at the front end of the second circumferential gap.

Abstract: A CO2 bottoming cycle system includes a first compressor operatively connected to a first turbine through a first shaft. A first generator is operatively connected to the first shaft. A second compressor is fluidically connected to the first compressor. The second compressor is operatively connected to a second turbine through a second shaft. A second generator is operatively connected to the second shaft. The first turbine is fluidically connected to the second turbine.

Abstract: A compressor bleed apparatus includes: a compressor comprising one or more rotors mounted for rotation about a central axis and enclosed in a compressor casing; a bleed slot passing through the compressor casing; an outer wall defining, in cooperation with the compressor casing, a plenum surrounding the compressor casing; at least one offtake pipe communicating with the plenum; and wherein at least one of the plenum and the bleed slot has a non-axisymmetric structure.

Abstract: A solid rocket motor is described that includes a solid propellant section, a nozzle, and a source of monopropellant, such as liquid monopropellant. The monopropellant is used to control various operational parameters of the solid rocket motor, such as thrust vector control, roll control, extinguishment of the motor, and cooling of the nozzle and/or nozzle throat. The nozzle and the nozzle throat can be an integrated, single piece assembly that facilitates re-use of the nozzle.

Abstract: A gas turbine engine including: a turbomachine coupled to a propeller of the gas turbine engine, the turbomachine being in fluid communication with an external environment through an air inlet; and an electric motor coupled to the propeller, wherein the air inlet is in fluid communication with a bypass duct having a selectively variable geometry.

Abstract: A disclosed drive assembly for an auxiliary power unit includes a first drive shaft driven by an auxiliary power unit, a second drive shaft driven by a first electric motor, a differential gear system including a ring gear driven by the second drive shaft, a and planet gears supported within a carrier attached to the ring gear. The first drive shaft and an output shaft are coupled to the planet gears and a generator is driven by the output shaft. The electric motor and the auxiliary power unit combine to drive the output shaft.

Abstract: Waste heat management systems are described. The waste heat management systems include a turbine engine having a compressor section, a combustor section, a turbine section, and a nozzle. The compressor section, the combustor section, the turbine section, and the nozzle define a core flow path that expels through the nozzle. The waste heat management systems also include an auxiliary power unit (APU) system and a waste heat recovery system operably connected to the APU system. The APU system is integrated into a working fluid flow path of the waste heat recovery system.