A turbine section of a turbomachine includes a housing that houses and supports the rotating group for rotation about an axis. The housing defines a circumferential inlet passage that extends about the axis. The housing defines a turbine wheel upstream area that is disposed downstream of the circumferential inlet passage and upstream of the turbine wheel. The housing defines an outlet that is downstream of the turbine wheel. Furthermore, the turbine section includes a first flow path that extends from the circumferential inlet passage, through the turbine wheel upstream area, across the turbine wheel, to the outlet. Moreover, the turbine section includes a recirculation flow path that extends from the circumferential inlet passage, through the turbine wheel upstream area, and back to the circumferential inlet passage.

A controller for a gas turbine wherein the gas turbine includes the compressor arranged to operate at a rotational speed n, the combustor and the fuel supply includes the first fuel supply and the second fuel supply, wherein the compressor is arranged to provide air to the combustor at a steady state air mass flow rate m.sub.ss and wherein the fuel supply is arranged to supply fuel at a fuel mass flow rate m.sub.total to the combustor. The controller is arranged to, responsive to the load change ΔL to the load L, control the fuel supply to supply a proportion Z of the fuel mass flow rate m.sub.total as a fuel mass flow rate m.sub.fuel pilot via the first fuel supply based, at least in part, on a combustor mass flow rate m.sub.t.

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.

The invention relates to a method for controlling a turbomachine comprising a gas generator, the turbomachine comprising an electric machine forming a device for injecting torque into/removing torque from one of the low pressure/high pressure rotation shafts of said gas generator. Said method comprises a step of implementing a fuel control loop in order to determine a fuel flow setpoint into the combustion chamber, and comprising, in the event that at least one operability limit is reached, determining a corrected fuel flow setpoint, said corrected fuel flow setpoint exhibiting a difference in relation to the setpoint. Said method also comprises a step of implementing a torque control loop in order to determine a torque setpoint for the electric machine, and comprising determining a torque correction quantity as a function of said difference, said torque setpoint being determined as a function of said torque correction quantity.

A sleeve valve includes an inlet port and an outlet port. A sleeve is movable to close flow from the inlet port to the outlet port. The sleeve valve has a sleeve biased to an open position at which it allows flow from the inlet port to the outlet port by a spring. Pressure in a pressure chamber urges the sleeve to a closed position at which it blocks flow from the inlet port to the outlet port. A line pressure conduit communicates the fluid chamber into the pressure chamber. Pressurized air is supplied to the pressure chamber through a selectively closed valve. The selectively closed valve is opened to allow the flow of high pressure air from a pressure source into the pressure chamber to move the sleeve to a closed position. A bleed air system for a gas turbine engine is also disclosed.

There is disclosed a centrifugal compressor including an impeller rotatable about an axis and a diffuser downstream of the impeller. The diffuser has walls delimiting flow passages. Plasma actuators are positioned adjacent the walls and are operatively connectable to a source of electricity. The plasma actuators have a first electrode, a second electrode, and a dielectric layer therebetween. The first electrode is upstream of the second electrode. The first electrode is exposed to the flow passage. The second electrode is shielded from the flow passage by the dielectric layer. The plasma actuators are operable to generate an electric field through the dielectric layer. The plasma actuators are located closer to inlets of the flow passage than to outlets of the flow passages. A method of operating the compressor is disclosed.

A system for bleeding air from a core flow path of a gas turbine engine is disclosed. In various embodiments, the system includes a bleed valve having a bleed valve inlet configured to receive a bleed air from a first access point to the core flow path and a bleed valve outlet; and an air motor having a first air motor inlet configured to receive the bleed air from the bleed valve outlet and a first air motor outlet configured to exhaust the bleed air, the air motor configured to pump the bleed air from the core flow path of the gas turbine engine.

A compressor for an aircraft engine. A rotor includes blades rotatable about an axis. Blade tips extend between leading and trailing edges. A shroud surrounds the rotor, with an inner surface surrounding the tips. Grooves are defined in the shroud inner surface adjacent the tips. The grooves extend circumferentially about the shroud and radially from inlet openings to closed end surfaces. Groove sidewalls extend circumferentially about the axis. The grooves are axially spaced-apart, the most upstream inlet opening having an upstream end disposed upstream of the leading edges of the blades. The grooves have a swept angle from the inner surface, with a center of the inlet openings is axially offset of a center of the closed-end surfaces. The grooves span an overall axial distance corresponding to 30% or more of the blades’ chord length. The grooves have circumferential interruptions defined by baffles, and extend non-continuously around a shroud circumference.

A gas turbine engine comprises at least one radially extending bleed passage optionally in fluid communication with at least one generally circumferentially extending plenum. The passage has an upstream inlet in fluid communication with a bleed passage and an outlet for releasing air from the plenum. The upstream leading edge of the inlet or the downstream trailing edge of the inlet has a non-uniform profile.

A jet engine which includes: a fan provided with a plurality of stages of rotor blades; a compressor which compresses air which is sent from the fan; a combustor which generates combustion gas by using compressed air generated by the compressor; a turbine which generates a driving force from the combustion gas; and a nozzle which discharges the combustion gas, the jet engine further includes: a variable guide vane which is disposed upstream of the rotor blades of a second and later stage of the rotor blades of the fan and which adjusts an inlet angle of air flow against the second and later stage of the rotor blades; a fluid resistance adjusting device which adjusts a fluid resistance at the nozzle; and a controller which controls the variable guide vane such that the inlet angle at the time of cruise flight is smaller than the inlet angle at the time of acceleration and controls the fluid resistance adjusting device such that increase in the fluid resistance, due to an increase in a volume flow at an outlet of the fan corresponding to a reduction in the inlet angle, is suppressed.