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:
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 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 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:
Variable stator vane assemblies and stator vanes thereof having a local swept leading edge are provided. The variable stator vane comprises an airfoil disposed between spaced apart inner and outer buttons centered about a rotational axis. The inner and outer buttons each have a button forward edge portion. The airfoil includes leading and trailing edges, pressure and suction sides, and a root and a tip. The leading edge, at least a portion of which extends forward of the buttons, includes a local forward sweep at the root, thereby forming a locally swept root of the leading edge thereat. The button forward edge portion of the inner button is substantially vertically aligned with the locally swept leading edge root. Methods are also provided for minimizing endwall leakage in the variable stator vane assembly using the same.
Abstract:
Methods are provided for improving performance of a gas turbine engine comprising a component having a rotor mounted in a rotor casing and having rotor blades. A tip sweep is applied to a leading edge of one or more rotor blades each having a pressure sidewall and a circumferentially opposing suction sidewall extending in a radial direction between a root and a tip and in an axial direction between the leading edge and a trailing edge. One or more blade geometric design parameters are adjusted. A rotor casing treatment is applied to the rotor casing over at least one of the one or more rotor blades. The applying and adjusting steps are performed during design of the rotor and cause a measured stall margin to substantially match a required stall margin with an increase in efficiency of the component.
Abstract:
Variable vane devices containing rotationally-driven translating vane structures are provided, as are methods for fabricating variable vane devices. In one embodiment, the variable vane device includes a flow assembly having a centerline, an annular flow passage extending through the flow assembly, cam mechanisms, and rotationally-driven translating vane structures coupled to the flow assembly and rotatable relative thereto. The translating vane structures include vane bodies positioned within the annular flow passage and angularly spaced about the centerline. During operation of the variable vane device, the cam mechanisms adjust translational positions of the vane bodies within the annular flow passage in conjunction with rotation of the translating vane structures relative to the flow assembly. By virtue of the translational movement of the translating vane structures, a reduction in the clearances between the vane bodies and neighboring flow assembly surfaces can be realized to reduce end gap leakage and boost device performance.
Abstract:
Embodiments of an impeller shroud support for disposition around an impeller are provided, as are embodiments of gas turbine engine including impeller shroud supports. In one embodiment, the impeller shroud support includes a shroud body, a support arm joined to and extending around the shroud body, and a plurality of Mid-Impeller Bleed (MIB) flow passages. Each MIB flow passage includes, in turn, an inlet formed in the shroud body and configured to receive bleed air extracted from the impeller, a throat portion, an outlet formed in the support arm and through which the bleed air is discharged, and a curved intermediate section between the inlet and the outlet. During usage of the impeller shroud support, the curved intermediate section turns the bleed air flowing through the MIB passage in a radially outward direction prior to discharge from the outlet of the MIB flow passage.
Abstract:
Methods are provided for improving performance of a gas turbine engine comprising a component having a rotor mounted in a rotor casing and having rotor blades. A tip sweep is applied to a leading edge of one or more rotor blades each having a pressure sidewall and a circumferentially opposing suction sidewall extending in a radial direction between a root and a tip and in an axial direction between the leading edge and a trailing edge. One or more blade geometric design parameters are adjusted. A rotor casing treatment is applied to the rotor casing over at least one of the one or more rotor blades. The applying and adjusting steps are performed during design of the rotor and cause a measured stall margin to substantially match a required stall margin with an increase in efficiency of the component.
Abstract:
Systems and methods for stable operation of a compressor of a gas turbine engine include axial stages, each including a series of rotor blades. A centrifugal stage has a centrifugal impeller disposed downstream from the axial stages. Air flows through the compressor first through the axial stages and then through the centrifugal stage. Each respective axial stage includes mechanisms for the avoidance of certain operating conditions of the compressor such as surge. The mechanisms include variable vane sets disposed upstream from a series of the rotor blades or a bleed port or ports around the respective axial stage downstream from the series of rotor blades to selectively extract air from the respective axial stage.