Abstract: A ported shroud for a compressor associated with a gas turbine engine includes a primary inlet configured to be in fluid communication with the compressor, and the primary inlet is defined to extend along a central axis of the ported shroud. The ported shroud includes a bellmouth that surrounds the primary inlet, and a port plenum configured to be in fluid communication with the compressor. The port plenum extends along an axis that is transverse to the central axis of the ported shroud and transverse to a direction of fluid flow. The port plenum has a port plenum inlet defined about the axis, and the port plenum inlet is defined through the bellmouth such that a tortuous path is defined to the port plenum inlet. The port plenum including a port plenum outlet downstream from the port plenum inlet configured to be in fluid communication with the compressor.

Abstract: An asymmetric inlet particle separator for a gas turbine engine includes an inlet having a first cross-sectional shape, and a duct downstream of the inlet. The duct includes a bend upstream from a splitter, a scavenge branch and an engine airflow branch. The splitter is outside of a line of sight from the inlet and the splitter separates the scavenge branch from the engine airflow branch. The asymmetric inlet particle separator includes an annulus downstream of the engine airflow branch configured to be coupled to the gas turbine engine. The annulus has a second cross-sectional shape, and the engine airflow branch transitions from the first cross-sectional shape to the second cross-sectional shape.

Abstract: A particle separator includes a housing through which a flow stream is directed. A number of guide vanes are disposed in the housing. The guide vanes have a profile wherein the flow stream is guided to follow the profile. The guide vanes have a wall surrounding an open interior that defines a vane plenum. A plurality of through-holes extend through the wall of the guide vane. The through-holes are open to the flow stream and to the vane plenum. A duct connects with the vane plenum and is configured to discharge particles collected in the vane plenum.

Abstract: A particle separator associated with a compressor section of a gas turbine engine includes a duct that defines a fluid flow path from a diffuser to a deswirl section. The duct includes a curved portion between an outlet of the diffuser and an inlet of the deswirl section. The curved portion is configured to have at least one low velocity region and a high velocity region. The particle separator includes at least one cluster of inlet passages defined at the at least one low velocity region. The particle separator includes a scavenge plenum coupled to the duct and in fluid communication with the at least one cluster of inlet passages. At least one outlet slot is defined through the duct downstream of the at least one cluster of inlet passages in the high velocity region and is in fluid communication with the scavenge plenum.

Abstract: An asymmetric inlet particle separator for a gas turbine engine includes an inlet having a first cross-sectional shape, and a duct downstream of the inlet. The duct includes a bend upstream from a splitter, a scavenge branch and an engine airflow branch. The splitter is outside of a line of sight from the inlet and the splitter separates the scavenge branch from the engine airflow branch. The asymmetric inlet particle separator includes an annulus downstream of the engine airflow branch configured to be coupled to the gas turbine engine. The annulus has a second cross-sectional shape, and the engine airflow branch transitions from the first cross-sectional shape to the second cross-sectional shape.

Abstract: A particle separator associated with a compressor section of a gas turbine engine includes a duct that defines a fluid flow path from a diffuser to a deswirl section. The duct includes a curved portion between an outlet of the diffuser and an inlet of the deswirl section. The curved portion is configured to have at least one low velocity region and a high velocity region. The particle separator includes at least one cluster of inlet passages defined at the at least one low velocity region. The particle separator includes a scavenge plenum coupled to the duct and in fluid communication with the at least one cluster of inlet passages. At least one outlet slot is defined through the duct downstream of the at least one cluster of inlet passages in the high velocity region and is in fluid communication with the scavenge plenum.

Abstract: A ported shroud for a compressor associated with a gas turbine engine includes a primary inlet configured to be in fluid communication with the compressor, and the primary inlet is defined to extend along a central axis of the ported shroud. The ported shroud includes a bellmouth that surrounds the primary inlet, and a port plenum configured to be in fluid communication with the compressor. The port plenum extends along an axis that is transverse to the central axis of the ported shroud and transverse to a direction of fluid flow. The port plenum has a port plenum inlet defined about the axis, and the port plenum inlet is defined through the bellmouth such that a tortuous path is defined to the port plenum inlet. The port plenum including a port plenum outlet downstream from the port plenum inlet configured to be in fluid communication with the compressor.

Abstract: A particle separator includes a housing through which a flow stream is directed. A number of guide vanes are disposed in the housing. The guide vanes have a profile wherein the flow stream is guided to follow the profile. The guide vanes have a wall surrounding an open interior that defines a vane plenum. A plurality of through-holes extend through the wall of the guide vane. The through-holes are open to the flow stream and to the vane plenum. A duct connects with the vane plenum and is configured to discharge particles collected in the vane plenum.

Abstract: An inlet door assembly for reducing air pressure loss and enhancing performance of an auxiliary power unit (APU) contained within an aircraft housing is provided. The inlet door assembly includes a duct and a diffuser. The duct, which is configured to be movably coupled to an aircraft and to move between open and closed positions, has a flow passage extending therethrough. Air external to the aircraft flows through the duct while it is in the open position, but not while it is in the closed position. The diffuser is coupled to the duct and configured to move therewith. The diffuser has a passage extending therethrough that is in fluid communication with the duct flow passage, and is configured to diffuse the air that flows therethrough.

Abstract: An auxiliary power unit (APU) compartment air inlet system seals, via one or more inlet doors driven by a single actuator, an APU compartment, and isolates the APU inlet and cooling system inlets from each other. The system includes either one or two inlet doors, depending on the number of ram air inlets formed in the APU compartment. In either instance, however, a single actuator is used to move the inlet door(s) between open and closed positions.

Abstract: An eductor assembly is provided that includes a primary nozzle, a cooler plenum, and a surge plenum. In one embodiment, and by way of example only, the primary nozzle is configured to accelerate and discharge turbine exhaust gas therefrom and the cooler plenum surrounds the primary nozzle and includes at least a fluid inlet and a fluid outlet. The surge plenum partially surrounds the primary nozzle and the cooler plenum and includes at least a fluid inlet and a fluid outlet. The surge plenum fluid outlet axially aligns and is coterminous with the cooler plenum fluid outlet.

Abstract: An aircraft inlet assembly is provided for damping noise from an auxiliary power unit (“APU”) of an aircraft having a tailcone including a sidewall with a first end and a second end, and an end wall coupled to the sidewall first end. The assembly includes a partition disposed within the tailcone and configured to divide the tailcone into a first compartment and a second compartment, the partition including an opening formed therein, an inlet opening formed in the tailcone sidewall in fluid communication with the first compartment, a first inlet duct extending between the inlet opening and the first compartment, an APU disposed within the second compartment, and a second inlet duct extending between the inlet opening and the partition opening to provide communication between the inlet opening and the second compartment.

Abstract: An inlet door assembly and method for reducing noise from an auxiliary power unit (APU) contained within an aircraft housing is provided. The inlet assembly includes an inlet duct, an actuator, and a door. The inlet duct is configured to extend from the auxiliary power unit to the aircraft housing and has a sidewall that defines a flow passage through which APU noise propagates. The actuator is disposed at least partially within the inlet duct. The door coupled to the actuator. The actuator is also configured to selectively rotate the door between at least a first position, in which at least a portion of the door deflects APU noise in a first direction, and a second position, in which at least a portion of the door deflects the APU noise in a second direction.

Abstract: An inlet door assembly and method for reducing noise from an auxiliary power unit (APU) contained within an aircraft housing is provided. The inlet assembly includes an inlet duct, an actuator, and a door. The inlet duct is configured to extend from the auxiliary power unit to the aircraft housing and has a sidewall that defines a flow passage through which APU noise propagates. The actuator is disposed at least partially within the inlet duct. The door coupled to the actuator. The actuator is also configured to selectively rotate the door between at least a first position, in which at least a portion of the door deflects APU noise in a first direction, and a second position, in which at least a portion of the door deflects the APU noise in a second direction.

Abstract: The present invention provides a means for inducing (educting) a “passive” secondary flow stream using an exhaust eductor system including a primary exhaust nozzle designed to transport an active flow stream and a plurality of tabs extending from a rear perimeter of the primary exhaust nozzle. Each of the tabs is designed to be bent at an angle in relation to the primary exhaust nozzle. An exhaust mixing duct is positioned around the primary exhaust nozzle that is designed to transport a passive flow stream to the active flow stream where the plurality of tabs create a streamwise vorticity to enhance the mixing of the active flow stream and the passive flow stream.

Abstract: An auxiliary power unit (APU) includes a compressor, a turbine, a combustor, and a starter-generator unit all integrated within a single containment housing. The turbine has an output shaft on which the compressor is mounted, and the starter-generator unit is coupled to the turbine output shaft without any intervening gears. The rotating components are all rotationally supported within the containment housing using bearings that do not receive a flow of lubricating fluid.

Abstract: A method and apparatus for dumping surge bleed air into a primary nozzle of a free gas turbine engine. The surge bleed air is introduced into gas turbine exhaust flow within the primary nozzle to create a mixed flow which may be used as a combined driver flow to compensate for reduced engine exhaust flow during periods when operation of the turbine engine may be exclusively dedicated to only electric load operation. The surge bleed air may not be the educted flow or the secondary driven flow, while cooling air passing through an oil cooler may be an educted flow. Surge bleed air may flow through, for example, mixer lobes, hollow struts, or the center body before mixing with the gas turbine exhaust flow.

Abstract: An inlet door assembly and method for reducing noise from an auxiliary power unit (APU) contained within an aircraft housing is provided. The inlet assembly includes an inlet duct, an actuator, and a door. The inlet duct is configured to extend from the auxiliary power unit to the aircraft housing and has a sidewall that defines a flow passage through which APU noise propagates. The actuator is disposed at least partially within the inlet duct. The door coupled to the actuator. The actuator is also configured to selectively rotate the door between at least a first position, in which at least a portion of the door deflects APU noise in a first direction, and a second position, in which at least a portion of the door deflects the APU noise in a second direction.

Abstract: A tailpipe for a gas turbine engine has a cylindrical portion and lobed portion. The lobed portion extends a length X and has a plurality of circumferentially disposed peaks and valleys. Over at least the first 30 percent of length X, the radius of the each valley is greater than the radius of each peak and is greater than 10% of the equivalent diameter DE. Also, the effective flow area at the end of the lobed portion is greater that the effective flow area at its beginning. The cylindrical portion includes a straight portion and a canted portion.

Abstract: A gas turbine engine (10) incorporates a particle trap (46) that forms an entrapment region (73) in a plenum (24) which extends from within the combustor (18) to the inlet (32) of a radial-inflow turbine (52, 54). The engine (10) is thereby adapted to entrap particles that originate downstream from the compressor (14) and are otherwise propelled by combustion gas (22) into the turbine (52, 54). Carbonaceous particles that are dislodged from the inner wall (50) of the combustor (18) are incinerated within the entrapment region (73) during operation of the engine (10).