Abstract: A turbine engine assembly includes a tap is at a location upstream of the combustor section where a bleed airflow is drawn. The bleed air is pressurized in an auxiliary compressor section, heated in an exhaust heat exchanger and expanded through a power turbine that is coupled to drive the auxiliary compressor section.

Abstract: A system for energy conversion that includes a propulsion system, a fuel circuit, a combustion device, a turbine, and a load device. The fuel circuit is in fluid communication with a fuel tank and a fuel flow control device that separates a flow of fuel into a first portion and a second portion. The combustion device receives a flow of oxidizer and the second portion of fuel to generate combustion gases. The turbine receives the combustion gases from the combustion device via a fluid circuit. The load device is operably coupled to the turbine via a driveshaft and is configured to receive torque from the driveshaft.

Abstract: A gas turbine engine for an aircraft and a method of operating a gas turbine engine on an aircraft. Embodiments disclosed include a gas turbine engine for an aircraft including: an engine core has a turbine, a compressor, and a core shaft; a fan located upstream of the engine core, the fan has a plurality of fan blades; a nacelle surrounding the engine core and defining a bypass duct and bypass exhaust nozzle; and a gearbox that receives an input from the core shaft and outputs drive to the fan wherein the gas turbine engine is configured such that a jet velocity ratio of a first jet velocity exiting from the bypass exhaust nozzle to a second jet velocity exiting from an exhaust nozzle of the engine core at idle conditions is greater by a factor of 2 or more than the jet velocity ratio at maximum take-off conditions.

Abstract: Aircraft propulsion systems including a closed loop-supercritical fluid system having a turbine, a cooler heat exchanger, a compressor, and a recovery heat exchanger arranged along a closed-loop flow path of a supercritical fluid. A shaft is operably coupled to the turbine and configured to be rotationally driven by the turbine. A fan is configured to generate thrust, the fan operably coupled to the shaft to be rotationally driven by the shaft. A burner is configured to combust a fuel and air from the fan to generate a combusted gas and supply said combusted gas to the recovery heat exchanger of the closed loop-supercritical fluid system and out an exhaust nozzle.

Abstract: 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.

Abstract: A method for in-flight monitoring of the health of an aero gas turbine engine including in flow series a compressor system, a core gas generator including a combustor, and a turbine, and further including a shaft system connecting the turbine to the compressor system and forming a torque path there between. The method includes: measuring a first rotational speed of a forward portion of the shaft system; measuring a second rotational speed of a rear portion of the shaft system; measuring other operational parameters of the engine; calculating from the measured rotational speeds the power delivered by the torque path from the turbine to the compressor system; calculating from the other measured operational parameters the power delivered to the turbine by the core gas generator; correlating the power delivered by the torque path at a given time with the power delivered to the turbine at that time.

Abstract: Methods and systems for operating an aircraft having two or more engines are described. The method comprises operating the two or more engines of the aircraft in an asymmetric operating regime, wherein a first of the engines is in an active mode to provide motive power to the aircraft and a second of the engines is in a standby mode to provide substantially no motive power to the aircraft, receiving a request to exit the asymmetric operating regime, the request having at least one parameter associated therewith, selecting one of a plurality of available exit protocols as a function of the at least one parameter, and applying the exit protocol by commanding the engines accordingly.

Abstract: In a gas turbine engine of the type having a high-pressure (HP) spool and a low-pressure (LP) spool, methods of increasing surge margin and compression efficiency at a given thrust are provided. One method increases compression efficiency and comprises transferring mechanical power from the HP spool to the LP spool to reduce a corrected speed of a HP compressor therein and raise a working line of a LP compressor therein. Another method increases surge margin and comprises transferring mechanical power from the LP spool to the HP spool to increase a corrected speed of a HP compressor therein and lower a working line of a LP compressor therein.

Abstract: An aircraft turbine engine includes a gas generator and a fan arranged upstream from the gas generator and configured to generate a main gas flow, one portion of which flows in a flow path of the gas generator to form a primary flow, and another portion of which flows in a flow path around the gas generator to form a secondary flow. The gas generator includes a low-pressure compressor that includes a rotor driving the fan. The turbine engine further includes an electric machine. The electric machine includes a rotor rotated by the rotor of the low-pressure compressor, and a stator extending around the rotor of the electric machine and configured to be cooled by the primary flow.

Abstract: A gas turbine engine includes a first spool associated with a diffuser and a primary combustor and a second spool associated with a secondary combustor. The first spool includes a first compressor and a first turbine mounted to a first shaft, and the second spool includes a second compressor and a second turbine mounted to a second shaft. An inlet duct fluidly connects the diffuser to the second compressor. An outlet duct assembly fluidly connects the second turbine to the diffuser and the primary combustor.

Abstract: An aspect includes a system for a gas turbine engine. The system includes one or more bleeds of the gas turbine engine and a control system configured to check one or more activation conditions of a dirt rejection mode in the gas turbine engine. A bleed control schedule of the gas turbine engine is adjusted to extend a time to hold the one or more bleeds of the gas turbine engine partially open at a power setting above a threshold based on the one or more activation conditions. One or more deactivation conditions of the dirt rejection mode in the gas turbine engine are checked. The dirt rejection mode is deactivated to fully close the one or more bleeds based on the one or more deactivation conditions.

Abstract: The relative position and orientation between an auxiliary gearbox and a casing of an aircraft engine can be set including engaging a localizing feature of the accessory gearbox with a localizing feature of the casing; and a load path between auxiliary gearbox can subsequently be defined including securing at least two brackets between the accessory gearbox and casing.

Abstract: A gas turbine engine includes a combustion section, a turbine section, and a compressor section. The combustion section includes a combustor casing, a combustor, a cooling duct, and an outer duct. The combustor casing defines at least in part a diffuser cavity and a fluid inlet. The combustor disposed is in the diffuser cavity. The cooling duct is in fluid communication with the fluid inlet in the combustor casing and is configured to transport a flow of cooled air. The outer duct surrounds at least a portion of the cooling duct and extends along a portion of an entire length of the cooling duct. The outer duct defines a gap with the cooling duct and is configured to transport a flow of buffer air. The turbine section is disposed downstream from the combustion section. The cooling duct is in fluid communication with the turbine section.

Abstract: Described herein are embodiments of systems and methods for the removal of a direct drive unit (DDU) housed in an enclosure, such as a direct drive turbine (DDT) connected to a gearbox for driving a driveshaft connected to a pump for use in hydraulic fracturing operations.

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 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: A pilot nozzle for a dual fuel turbine engine includes an inner air circuit, a gaseous fuel circuit radially outward from the inner air circuit, a liquid fuel circuit radially outward from the inner air circuit, an outer air circuit radially outward from the liquid fuel circuit and the gaseous fuel circuit, and a shroud radially outward from the outer air circuit. The shroud is configured to stabilize a pilot re-circulation zone downstream from outlets of the inner and outer air circuits and the liquid and gaseous fuel circuits.

Abstract: An inertial particle separator (IPS) for a gas turbine engine, has: inner and outer walls extending about a central axis, an inlet defined between the inner and outer walls and oriented axially; swirling vanes extending at least radially between the inner and outer walls and circumferentially distributed around the central axis, the swirling vanes configured for inducing a circumferential component in an airflow flowing between the swirling vanes; a plenum between the inner and outer walls downstream of the swirling vanes, the plenum circumferentially extending about the central axis, the outer wall converging toward the central axis in a direction of the airflow; and a splitter radially between the inner and outer walls downstream of the plenum and circumferentially extending around the central axis, a particle outlet radially between the splitter and the outer wall, an air outlet radially between the inner wall and the splitter.

Abstract: Hybrid propulsion is obtained by arranging, around a conventional turbomachine, a reversible electric machine linked to the low-pressure shaft via a mechanical movement transmission, a one-way clutch being arranged on the low-pressure shaft between the fan and a low-pressure compressor. The low-pressure shaft includes two aligned portions which can be separated and reconnected. A casing includes a first portion able to tilt around a horizontal transverse axis of the aircraft relative to a second portions of the casing. One portion of the low-pressure shaft, the fan and the reversible electric machine are mounted on the first portion of the casing, and the other portion of the low-pressure shaft is mounted on the second portion of the casing. This device facilitates electric taxiing of the aircraft, using the machine as a motor, whereas the rear of the low-pressure shaft remains stationary.