A bleed valve includes a housing with an inlet coupled to an outlet by a duct, a guide tube with an orifice fixed in the housing between the inlet and the outlet, a piston, and baffle. The piston is slideably supported on the guide tube and is movable between an open and a closed position, the duct fluidly coupling the inlet and outlet in the open position, the duct fluidly separating the inlet and outlet in the closed position. The orifice fluidly couples the inlet and outlet in the open and closed positions to move piston between the open and closed positions according to differential pressure between the bleed valve inlet and outlet. The baffle is slideably supported by the guide tube to set the differential pressure at which the piston moves between the open and closed positions. Gas turbines and differential pressure adjustment methods are also described.

A method includes receiving a command to operate a power load of a power system at a command output power while operating the power load at a reference output power; operating a gas turbine engine of the power system in a maximum regulator mode to increase a power generation of the gas turbine engine when the command output power is greater than the reference output power or in a minimum regulator mode to decrease the power generation of the gas turbine engine when the command output power is less than the reference output power; and coordinating an electric machine power draw from the gas turbine engine with a change in power generation of the gas turbine engine to maintain a rotational speed parameter of the gas turbine engine substantially constant while operating the gas turbine engine in the maximum regulator mode or in the minimum regulator mode.

A controller for a gas turbine is arranged to supply a load L. The gas turbine includes a fuel supply arranged to supply fuel at a fuel flow rate FF to a combustor, wherein the fuel supply includes a first fuel supply and a second fuel supply. The controller is arranged to determine one or more ratios R of one or more combustor operating parameters COP respectively at the load L to respective reference combustor operating parameters COPR at a reference load LR. The controller is further arranged to control a proportion P of the fuel flow rate FF supplied via the first fuel supply based, at least in part, on the determined one or more ratios R. A gas turbine with the controller and a method controls the gas turbine.

There is provided a non-contacting seal assembly for a gas turbine engine, having a housing that houses a sealing ring; and a counter component cooperating with the sealing ring. The sealing ring and the counter component are rotatable relative to each other about a central axis and define sealing faces circumferentially extending around the central axis. The sealing faces face each other and are spaced apart from each other by a controlled gap. At least one of the sealing faces is coated with a non-abradable material. A method of operating a non-contacting seal assembly is also provided.

Methods, apparatus, systems and articles of manufacture are disclosed. A shroud assembly of a gas turbine engine includes: a first shroud arm having a first end and a second end, the first end to couple to an outer wall and the second end to couple to a first shroud pad, and a second shroud arm having a first end and a second end, the first end to couple to the outer wall and the second end to couple to a second shroud pad, at least one of the first shroud pad or the second shroud pad to move radially outward toward the outer wall in response to a rotor blade contacting the at least one of the first shroud pad or the second shroud pad.

A bleed valve includes a housing with an inlet coupled to an outlet by a duct. A guide tube is fixed within the housing between the inlet and the outlet. A piston with a piston orifice is slideably supported on the guide tube and movable between an open position and a closed position. The duct fluidly couples the inlet to the outlet in the open position, the duct fluidly separates the inlet from the outlet in the closed position, and the piston orifice fluidly couples the inlet with the outlet in the open position and the closed position to move piston between the open position and the closed position according to differential in pressure between the inlet and the outlet of the bleed valve. Compressors, gas turbine engines, and methods of controlling fluid flow are also described.

A plate for supporting a plurality of nozzle tubes in a combustion casing of a combustor stably supports the nozzle tubes and adsorbs displacement due to thermal expansion or natural vibrations, thereby reducing combustor maintenance and extending the lifetime of the combustor. The plate includes an inner frame having a plurality of through holes for respectively receiving the plurality of nozzle tubes; a fixing frame fixed on an inner circumferential surface of the combustion casing and configured to support the inner frame; and a mechanical buffer disposed between the fixing frame and the inner frame. The fixing frame has an inner circumferential surface in which a fixing recess having a U-shaped cross-section is formed to receive the mechanical buffer and an outer edge of the inner frame and to receive the mechanical buffer. A method of assembly the nozzle tube support plate facilitates its initial installation and subsequent maintenance.

An anti-ice arrangement for a gas turbine engine may comprise an engine static structure, a fan blade housed for rotation within the engine static structure, and a magnetic field source mounted in close proximity to the fan blade and configured for inducing eddy currents in the fan blade to increase a surface temperature of the fan blade.

The subject matter of the present disclosure is directed to a turbine engine having an adaptive prognostic health management control system that passively monitors stall margin reductions and applies corrective trims to a power management schedule of the engine to recover operability over time whilst maintaining a sufficient level of stall margin over the life cycle of the engine. The control system can adjust the power management schedule as needed to sustain a target stall margin, which allows for a more optimized and gradual performance to operability trade-off.

A checking method for checking a power plant of an aircraft, the power plant, comprising at least one engine and an air inlet, for feeding said at least one engine with air, the power plant including a cloggable filter filtering the air upstream from the engine. An aircraft power check is performed by: determining, in flight or on the ground, the current power actually being developed by the engine without making any allowance for any power losses resulting from the engine being installed in the aircraft or from a level of clogging of the filter, the aircraft power check being considered as being successful when the current power is greater than or equal to a guaranteed minimum power.