Abstract: A gas turbine engine includes a combustor having a combustor air inlet, an axial-centrifugal compressor, a shroud, a secondary flow duct, and a valve. The shroud surrounds at least a portion of the axial-centrifugal compressor and has a surge bleed plenum defined therein that is in fluid communication with, and receives compressed air from, the axial compressor outlet. The secondary airflow duct has a duct inlet that is in fluid communication with the surge bleed plenum, and a duct outlet that is in fluid communication with the combustor air inlet. The valve is mounted on the secondary airflow duct and is movable between a closed position, in which the secondary airflow duct does not provide fluid communication between the surge bleed plenum and the combustor air inlet, and an open position, in which the secondary airflow duct provides fluid communication between the surge bleed plenum and the combustor air inlet.

Abstract: A gas turbine engine includes a combustor having a combustor air inlet, an axial-centrifugal compressor, a shroud, a secondary flow duct, and a valve. The shroud surrounds at least a portion of the axial-centrifugal compressor and has a surge bleed plenum defined therein that is in fluid communication with, and receives compressed air from, the axial compressor outlet. The secondary airflow duct has a duct inlet that is in fluid communication with the surge bleed plenum, and a duct outlet that is in fluid communication with the combustor air inlet. The valve is mounted on the secondary airflow duct and is movable between a closed position, in which the secondary airflow duct does not provide fluid communication between the surge bleed plenum and the combustor air inlet, and an open position, in which the secondary airflow duct provides fluid communication between the surge bleed plenum and the combustor air inlet.

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 gas turbine engine includes a shroud with an abradable section and a non-abradable section that cooperatively define a shroud surface. The gas turbine engine also includes a rotor that is supported for rotation within the shroud to generate an aft axial fluid flow. The rotor includes a blade with a blade tip that is crowned and that opposes the abradable section and the non-abradable section of the shroud surface. A crown area of the blade tip opposes the abradable section. A casing treatment feature is provided in the non-abradable section of the shroud to oppose the blade tip of the rotor.

Abstract: A rotor for a compressor includes a hub and a plurality of airfoils having a root, a tip opposite the root and a span that extends from 0% at the root to 100% at the tip. Each of the airfoils is coupled to the hub at the root and is spaced apart from adjacent ones of the airfoils over the span by a throat dimension. The throat dimension has a maximum value at a spanwise location between 60% of the span and 90% of the span of the adjacent ones of the airfoils. The throat dimension between 90% of the span and the tip of the adjacent ones of the plurality of airfoils has a first value that is less than 70% of the maximum value.

Abstract: A rotor for a turbofan booster section associated with a fan section of a gas turbine engine includes a rotor blade having an airfoil having a leading edge, a trailing edge and a mean camber line. The airfoil has a delta inlet blade angle defined as a difference between a local inlet blade angle defined in a spanwise location, and a root inlet blade angle defined at the root. The delta inlet blade angle decreases in the spanwise direction from the root to a minimum value at greater than 10% span and from the minimum value, the delta inlet blade angle increases to the tip. The rotor includes a rotor disk coupled to the rotor blade configured to be coupled to the shaft or the fan to rotate with the shaft or the fan, respectively, at the same speed as the shaft or the fan.

Abstract: High performance wedge diffusers utilized within compression systems, such as centrifugal and mixed-flow compression systems employed within gas turbine engines, are provided. In embodiments, the wedge diffuser includes a diffuser flowbody and tapered diffuser vanes, which are contained in the diffuser flowbody and which partition or separate diffuser flow passages or channels extending through the flowbody. The diffuser flow channels include, in turn, flow channel inlets formed in an inner peripheral portion of the diffuser flowbody, flow channel outlets formed in an outer peripheral portion of the diffuser flowbody, and flow channel throats fluidly coupled between the flow channel inlets and the flow channel outlets. The diffuser vanes include a first plurality of vane sidewalls, which transition from linear sidewall geometries to non-linear sidewall geometries at locations between the flow channel inlets and the flow channel outlets.

Abstract: A rotor for a turbofan booster section associated with a fan section of a gas turbine engine includes a rotor blade having an airfoil extending from a root to a tip and having a leading edge and a trailing edge. The airfoil has a plurality of chord lines spaced apart in a spanwise direction. Each chord line of the plurality of chords lines is defined between the leading edge and the trailing edge and has a normalized chord value. From the hub, the normalized chord value decreases to a minimum value between about 20% to about 90% span and increases from the minimum value to the tip. The rotor includes a rotor disk coupled to the rotor blade configured to be coupled to the shaft or the fan to rotate with the shaft or the fan, respectively, at the same speed as the shaft and fan.

Abstract: A rotor blade for a compressor of a gas turbine engine includes an airfoil. The airfoil has a span that extends from 0% at the root to 100% at the tip and a mean camber line that extends from a leading edge to a trailing edge. The airfoil has a location of local maximum thickness defined as a ratio of a first arc distance along the mean camber line between the leading edge and a position of the local maximum thickness to a total arc distance along the mean camber line from the leading edge to the trailing edge. A value of the ratio increases from the root to a first position value, decreases from the first position value to a second position value and increases from the second position value to the tip. The first position value is at a spanwise location within 20% to 50% of the span.

Abstract: A rotor for a turbofan booster section associated with a fan section of a gas turbine engine includes a rotor blade having an airfoil extending from a root to a tip and having a leading edge and a trailing edge. The airfoil has a plurality of chord lines spaced apart in a spanwise direction. Each chord line of the plurality of chords lines is defined between the leading edge and the trailing edge and has a normalized chord value. From the hub, the normalized chord value decreases to a minimum value between about 20% to about 90% span and increases from the minimum value to the tip. The rotor includes a rotor disk coupled to the rotor blade configured to be coupled to the shaft or the fan to rotate with the shaft or the fan, respectively, at the same speed as the shaft and fan.

Abstract: A rotor for a turbofan booster section associated with a fan section of a gas turbine engine includes a rotor blade having an airfoil having a leading edge, a trailing edge and a mean camber line. The airfoil has a delta inlet blade angle defined as a difference between a local inlet blade angle defined a spanwise location, and a root inlet blade angle defined at the root. The delta inlet blade angle decreases in the spanwise direction from the root to a minimum value at greater than 10% span and from the minimum value, the delta inlet blade angle increases to the tip. The rotor includes a rotor disk coupled to the rotor blade configured to be coupled to the shaft or the fan to rotate with the shaft or the fan, respectively, at the same speed as the shaft and the fan.

Abstract: A rotor for a turbofan booster section associated with a fan section of a gas turbine engine includes a rotor blade having an airfoil extending in a spanwise direction from 0% span at a root to 100% span at a tip and having a leading edge and a trailing edge. The airfoil has a plurality of spanwise locations between the root and the tip each having a normalized local maximum thickness. A value of the normalized local maximum thickness decreases from the root to a minimum value and increases from the minimum value to the tip, and the minimum value is within 60% span to 90% span. The rotor includes a rotor disk coupled to the rotor blade configured to be coupled to a shaft or a fan to rotate with the shaft or the fan, respectively, at the same speed as the shaft and the fan.

Abstract: A rotor blade for a compressor of a gas turbine engine includes an airfoil extending from a root to a tip and having a leading edge and a trailing edge. The airfoil has a span that extends from 0% at the root to 100% at the tip and a mean camber line that extends from the leading edge to the trailing edge. The airfoil has a total camber distribution that increases from the root to a maximum value of total camber between 5% of the span and 20% of the span.

Abstract: A method of manufacturing a multistage axial-centrifugal compressor for a gas turbine engine and a multistage axial-centrifugal compressor that includes a series of axial compressor stages each having a rotor mounted to a common shaft positioned upstream from a centrifugal compressor stage mounted to the common shaft. The method includes determining an operational rotor tip speed for each of the axial stages. The method includes comparing the operational rotor tip speed to a threshold range value and determining to machine an airfoil of the rotor for at least one of the axial stages by an arbitrary manufacturing approach based on the operational rotor tip speed as greater than the threshold range value. The method includes determining to machine an airfoil of the rotor for at least one of the axial stages by a flank manufacturing approach based on the operational rotor tip speed as less than the threshold range value.

Abstract: A system and method for determining particulate accumulation in a gas turbine engine includes sensing the number, size, and type of particulate at a first position on the gas turbine engine and supplying first data representative thereof, where the first position located at a first side of a gas turbine engine component; sensing the number, size, and type of particulate at a second position on the gas turbine engine and supplying first data representative thereof, where the second position located at a second side of the gas turbine engine component and downstream of the first position; and processing the first data and the second data to determine the mass of the particulate accumulated on the gas turbine engine component.

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 positon 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 for a compressor includes a hub and a plurality of airfoils having a root, a tip opposite the root and a span that extends from 0% at the root to 100% at the tip. Each of the airfoils is coupled to the hub at the root and is spaced apart from adjacent ones of the airfoils over the span by a throat dimension. The throat dimension has a maximum value at a spanwise location between 60% of the span and 90% of the span of the adjacent ones of the airfoils. The throat dimension between 90% of the span and the tip of the adjacent ones of the plurality of airfoils has a first value that is less than 70% of the maximum value.

Abstract: A compressor section includes a shroud surface and a rotor with a blade tip that opposes the shroud surface. The rotor is configured to rotate within the shroud about an axis of rotation. Moreover, the compressor section includes a serration groove that is recessed into the shroud surface. The serration groove includes a forward portion with a forward transition and a forward surface that faces in the downstream direction. The forward transition is convexly contoured between the shroud surface and the forward surface. The serration groove includes a trailing portion with a taper surface and a trailing transition. The taper surface tapers inward as the taper surface extends from the forward surface to the trailing transition. The trailing transition is convexly contoured between the taper surface and the shroud surface.

Abstract: Circumferentially-split diffuser assemblies utilized within compression systems, such as centrifugal and mixed-flow compression systems employed within gas turbine engines, are provided. In embodiments, the diffuser assembly includes flow passages, which extend through the diffuser assembly and which include diffuser flow passage sections. Diffuser airfoils are interspersed with the diffuser flow passage sections. The diffuser airfoils include inboard and outboard airfoil segments distributed around a diffuser assembly centerline. The inboard and outboard airfoil segments are contained in and, thus, defined by inner and outer annular diffuser structures, respectively. The outer annular diffuser structure circumscribes the inner annular diffuser structure.

Abstract: High performance wedge diffusers utilized within compression systems, such as centrifugal and mixed-flow compression systems employed within gas turbine engines, are provided. In embodiments, the wedge diffuser includes a diffuser flowbody and tapered diffuser vanes, which are contained in the diffuser flowbody and which partition or separate diffuser flow passages or channels extending through the flowbody. The diffuser flow channels include, in turn, flow channel inlets formed in an inner peripheral portion of the diffuser flowbody, flow channel outlets formed in an outer peripheral portion of the diffuser flowbody, and flow channel throats fluidly coupled between the flow channel inlets and the flow channel outlets. The diffuser vanes include a first plurality of vane sidewalls, which transition from linear sidewall geometries to non-linear sidewall geometries at locations between the flow channel inlets and the flow channel outlets.