Abstract: A compressor for a turbine engine includes a shroud having a grooved section including a plurality of groove segments extending radially into a shroud surface. A rotor assembly rotatably supported in the shroud includes a rotor hub and a plurality of rotor blades. Each rotor blade extends radially from the rotor hub and terminates at a blade tip, which is spaced from the shroud surface by a tip gap and defines a non-constant clearance region between a leading edge position and a medial chord position along the blade chord at the minimum tip clearance. The rotor blades generate an aft axial fluid flow through the shroud and the grooved section is formed in the shroud surface upstream of the medial chord position within the non-constant clearance region for resisting a reverse axial fluid flow through the tip gap when the compressor section is operated at near stall conditions.

Abstract: A rotor includes a plurality of airfoils and each airfoil has a span that extends from 0% at a root to 100% at a tip, a chord that extends from 0% at a leading edge to 100% at a trailing edge and a pressure side opposite a suction side. The pressure side of each airfoil has a pressure side surface shape and the suction side of each airfoil has a suction side surface shape based on an operating state of the rotor. Each airfoil has the same suction side surface shape between 10% and 90% of the chord and between 80% and 100% of the span at a first state. At least one first airfoil has a different suction side surface shape between 10% and 90% of the chord and between 80% and 100% of the span than at least one second airfoil at a static state of the rotor.

Abstract: A system and method for determining particulate accumulation in a gas turbine engine includes sensing particulate at a first position that is located at a first side of a gas turbine engine component and supplying a first sensor signal representative thereof, and sensing particulate at a second position that is located at a second side of the gas turbine engine component and downstream of the first position, and supplying a second sensor signal representative thereof, where the second position. The first sensor and second sensor signals are processed to determine the type, quantity, and size of particulate at the first and second positions, respectively. Based at least on the quantity and size of the particulate at the first and the second positions, an amount of the particulate accumulated on the gas turbine engine component is determined.

Abstract: A blisk fan is provided for a turbine engine propulsion system. The blisk fan includes a hub configured to rotate about a rotational axis at a maximum rotational speed, and a plurality of blades extending radially outward from the hub to define a fan leading edge tip diameter. Each of the blades has a first vibratory mode at a natural frequency, which is greater than a first fan order and less than a second fan order at the maximum rotational speed. The compression system preferably has a balance factor of the compression system between 1.9 and 3.2.

Abstract: A propulsion and electric power generation system includes a gas turbine propulsion engine, an electrical generator, an aircraft power distribution system, a plurality of auxiliary fans, and a controller. The gas turbine propulsion engine includes at least a low-pressure turbine coupled to a fan via a low-pressure spool, and the low-pressure turbine is configured to generate mechanical power. The electrical generator is directly connected to the low-pressure spool and generates a total amount of electrical power (Pe). The aircraft power distribution system receives a first fraction (Pa) of the total amount of electrical power. The auxiliary fans receive a second fraction (Pf) of the total amount of electrical power. The controller is configured to control a ratio of Pf to Pa (Pf/Pa) such that the ratio spans a range from less than 0.6 to at least 0.9.

Abstract: The present disclosure provides systems and apparatuses for use in turbine systems that integrate structural frame elements into a variable-vectoring flow control configuration in order to reduce the weight and length of such turbine systems. In one exemplary embodiment, an apparatus for directing a gas flow includes an annular outer structural casing, an annular central hub disposed within the outer structural casing, and a plurality of structural support elements extending radially between the central hub and the outer structural casing. The apparatus further includes a plurality of positionally-fixed, variable-vectoring flow control bodies extending radially between the central hub and the outer structural casing and positioned circumferentially along the central hub between ones of the plurality of structural support elements.

Abstract: The present disclosure provides systems and apparatuses for use in turbine systems that integrate structural frame elements into a variable-vectoring flow control configuration in order to reduce the weight and length of such turbine systems. In one exemplary embodiment, an apparatus for directing a gas flow includes an annular outer structural casing, an annular central hub disposed within the outer structural casing, and a plurality of structural support elements extending radially between the central hub and the outer structural casing. The apparatus further includes a plurality of positionally-fixed, variable-vectoring flow control bodies extending radially between the central hub and the outer structural casing and positioned circumferentially along the central hub between ones of the plurality of structural support elements.

Abstract: A propulsion and electric power generation system includes a dual-spool turbofan gas turbine engine and an electrical generator. The dual-spool turbofan gas turbine engine includes at least a low-pressure turbine coupled to a fan via a low-pressure spool. The low-pressure turbine is configured to generate mechanical power. The electrical generator is directly connected to the low-pressure spool and is disposed downstream of the low-pressure turbine. A first fraction of the mechanical power generated by the low-pressure turbine is controllably supplied to the fan for propulsive power generation (Pt). A second fraction of the mechanical power generated by the low-pressure turbine is controllably supplied to the electrical generator for electrical power generation (Pe). A ratio of Pe to Pt (Pe/Pt), during operation of the dual-spool turbofan gas turbine engine, controllably spans a range from less than about 0.06 to at least 0.18.

Abstract: A turbine engine incorporating a fine particle separation means includes a radial compressor that rotates about a longitudinal axis, a radially-oriented diffuser located downstream and radially outward, with respect to the longitudinal axis, from the radial compressor, and a flow path positioned downstream and radially outward, with respect to the longitudinal axis, from the diffuser, wherein the flow path comprises an outer annular wall and an inner annular wall between which the compressed air flows, and wherein the flow path comprises an arc the redirects the compressed air from flowing in a substantially radial flow direction to a substantially axial flow direction. The turbine engine further includes an extraction slot in the outer annular wall that fluidly connects with a scavenge plenum, the scavenge plenum being positioned adjacent to and radially outward from the outer annular wall at a position downstream axially along the flow path from the arc.

Abstract: Methods and apparatus are provided for an axi-centrifugal compressor in a gas turbine engine for a business aviation or rotorcraft propulsion unit. The compressor includes an axial compressor section operable to affect a first pressure ratio along the flow path between a compressor inlet and a first section exit, and a centrifugal compressor section operable to affect a second pressure ratio along the flow path between a second section inlet and the compressor exit. The pressure rise across the axial and centrifugal compressor section is configured to have a tuning factor is in a range between 2.8 and 4.5 and a loading factor in a range between 0.6 and 0.8.

Abstract: A compressor includes a rotor platform; a rotor blade; and a casing having an inner surface surrounding the tip and spaced radially outwardly from the tip to define a gap. A secondary air flow system includes a bleed inlet configured to remove secondary air flow from the primary air flow; an injection opening disposed in the inner surface of the casing upstream of the bleed inlet; an accessory conduit; and a plenum fluidly coupled to the bleed inlet, the injection opening, and the accessory conduit. The bleed inlet and plenum at least partially define a secondary air flow path such that a first portion of the secondary air flow is directed in through the bleed inlet, through the plenum, and out through the injection opening and a second portion of the secondary air flow is directed in through the bleed inlet, through the plenum, and out through the accessory conduit.

Abstract: A system and method for determining particulate accumulation in a gas turbine engine includes sensing particulate at a first position that is located at a first side of a gas turbine engine component and supplying a first sensor signal representative thereof, and sensing particulate at a second position that is located at a second side of the gas turbine engine component and downstream of the first position, and supplying a second sensor signal representative thereof, where the second position. The first sensor and second sensor signals are processed to determine the type, quantity, and size of particulate at the first and second positions, respectively. Based at least on the quantity and size of the particulate at the first and the second positions, an amount of the particulate accumulated on the gas turbine engine component is determined.

Abstract: A compressor includes a rotor platform; a rotor blade; and a casing having an inner surface surrounding the tip and spaced radially outwardly from the tip to define a gap. A secondary air flow system includes a bleed inlet configured to remove secondary air flow from the primary air flow; an injection opening disposed in the inner surface of the casing upstream of the bleed inlet; an accessory conduit; and a plenum fluidly coupled to the bleed inlet, the injection opening, and the accessory conduit. The bleed inlet and plenum at least partially define a secondary air flow path such that a first portion of the secondary air flow is directed in through the bleed inlet, through the plenum, and out through the injection opening and a second portion of the secondary air flow is directed in through the bleed inlet, through the plenum, and out through the accessory conduit.

Abstract: Embodiments of a core-protecting fan module are provided, as are embodiments of a turbofan engine containing such a fan module. In an embodiment, the core-protecting fan module contains a nose member, a fan rotor downstream of the nose member, a full span stator downstream of the fan rotor, and a splitter structure downstream of the fan rotor. The fan rotor includes a plurality of fan blades, which extends from a rotor hub and which is angularly spaced about a rotational axis. Certain fundamental angular relationships are observed between the angles formed by rotational axis, the nose member, the fan rotor, and a leading edge of the splitter structure to reduce contaminant ingestion by the core flow path and to promote moisture shedding to reduce susceptibility to icing within the fan module, while further avoiding or minimizing negative impacts to other structural and functional aspects of the turbofan engine.

Abstract: A compressor for a turbine engine includes a shroud having a grooved section including a plurality of groove segments extending radially into a shroud surface. A rotor assembly rotatably supported in the shroud includes a rotor hub and a plurality of rotor blades. Each rotor blade extends radially from the rotor hub and terminates at a blade tip, which is spaced from the shroud surface by a tip gap and defines a non-constant clearance region between a leading edge position and a medial chord position along the blade chord at the minimum tip clearance. The rotor blades generate an aft axial fluid flow through the shroud and the grooved section is formed in the shroud surface upstream of the medial chord position within the non-constant clearance region for resisting a reverse axial fluid flow through the tip gap when the compressor section is operated at near stall conditions.

Abstract: Multistage gas turbine engine (GTE) compressors having optimized stall enhancement feature (SEF) configurations are provided, as are methods for the production thereof. The multistage GTE compressor includes a series of axial compressor stages each containing a rotor mounted to a shaft of a gas turbine engine. In one embodiment, the method includes the steps or processes of selecting a plurality of engine speeds distributed across an operational speed range of the gas turbine engine, identifying one or more stall limiting rotors at each of the selected engine speeds, establishing an SEF configuration in which SEFs are integrated into the multistage GTE compressor at selected locations corresponding to the stall limiting rotors, and producing the multistage GTE compressor in accordance with the optimized SEF configuration.

Abstract: Multistage gas turbine engine (GTE) compressors having optimized stall enhancement feature (SEF) configurations are provided, as are methods for the production thereof. The multistage GTE compressor includes a series of axial compressor stages each containing a rotor mounted to a shaft of a gas turbine engine. In one embodiment, the method includes the steps or processes of selecting a plurality of engine speeds distributed across an operational speed range of the gas turbine engine, identifying one or more stall limiting rotors at each of the selected engine speeds, establishing an SEF configuration in which SEFs are integrated into the multistage GTE compressor at selected locations corresponding to the stall limiting rotors, and producing the multistage GTE compressor in accordance with the optimized SEF configuration.

Abstract: A blisk fan is provided for a turbine engine propulsion system. The blisk fan includes a hub configured to rotate about a rotational axis at a maximum rotational speed, and a plurality of blades extending radially outward from the hub to define a fan leading edge tip diameter. Each of the blades has a first vibratory mode at a natural frequency, which is greater than a first fan order and less than a second fan order at the maximum rotational speed. The compression system preferably has a balance factor of the compression system between 1.9 and 3.2.

Abstract: A turbine engine incorporating a fine particle separation means includes a radial compressor that rotates about a longitudinal axis, a radially-oriented diffuser located downstream and radially outward, with respect to the longitudinal axis, from the radial compressor, and a flow path positioned downstream and radially outward, with respect to the longitudinal axis, from the diffuser, wherein the flow path comprises an outer annular wall and an inner annular wall between which the compressed air flows, and wherein the flow path comprises an arc the redirects the compressed air from flowing in a substantially radial flow direction to a substantially axial flow direction. The turbine engine further includes an extraction slot in the outer annular wall that fluidly connects with a scavenge plenum, the scavenge plenum being positioned adjacent to and radially outward from the outer annular wall at a position downstream axially along the flow path from the arc.

Abstract: Methods and apparatus are provided for an axi-centrifugal compressor in a gas turbine engine for a business aviation or rotorcraft propulsion unit. The compressor includes an axial compressor section operable to affect a first pressure ratio along the flow path between a compressor inlet and a first section exit, and a centrifugal compressor section operable to affect a second pressure ratio along the flow path between a second section inlet and the compressor exit. The pressure rise across the axial and centrifugal compressor section is configured to have a tuning factor is in a range between 2.8 and 4.5 and a loading factor in a range between 0.6 and 0.8.