Abstract: A gas turbine engine shut-down system includes a pump configured to draw a flow of fuel from a source, a fuel nozzle configured to receive the flow of fuel from the pump, a fuel shut-off valve in fluid communication with the pump, a recirculation circuit for circulating excess fuel to a location upstream of the pump; a solenoid valve in communication with the pump and the recirculation circuit; and a fuel-bypass valve. The fuel-bypass valve includes a first opening connected to the fuel pump, a second opening connected to the fuel shut-off valve, a third opening connected to the recirculation circuit, a fourth opening connected to the solenoid valve, and a piston disposed within the fuel-bypass valve and movable between a plurality of positions.

Abstract: A fuel system for a turbomachine includes a minimum pressure and shutoff valve (MPSOV) disposed between a fuel source and a fuel nozzle of a fuel system and configured to move between an opened position wherein fuel can flow to the fuel nozzle, and a closed position wherein fuel is prevented from flowing to the fuel nozzle, and a shutdown signal valve (SDSV) operatively connected to the MPSOV and configured to selectively supply a shutdown pressure to the MPSOV in a shutdown state such that the shutdown pressure forces the MPSOV to the closed position.

Abstract: A bleed valve assembly includes a flow duct with an inlet and an outlet disposed downstream from the inlet. The outlet is smaller in cross-sectional area than a region of the flow duct disposed between the inlet and the outlet. A piston housing is disposed inside the flow duct between the inlet and the outlet so as to form an annular flow passage between the flow duct and the piston housing. The piston housing is axially aligned with a center axis of the flow duct. At least one rib extends between the flow duct and the piston housing. A sleeve piston is disposed inside the piston housing and is configured to extend downstream of the piston housing in a closed position. The sleeve piston comprises an outer wall that is at least the same in cross-sectional area as the outlet of the flow duct.

Abstract: A filter assembly for a fluid flow system includes a filter housing, a housing inlet to allow the fluid flow into the filter housing and a housing outlet to allow the fluid flow to exit the filter housing. A filter element is located in the filter housing to collect contaminants from the fluid flow. A pressure sensor is located to measure a pressure drop across the filter element. The pressure sensor includes at least one sense line extending into an interior volume of the filter housing. A method of monitoring a filter assembly for a fluid flow system includes positioning a pressure sensor at a filter assembly, extending at least one sense line from the pressure sensor into an internal volume of a filter housing of the filter assembly, and measuring a pressure drop across a filter element of the filter assembly via the pressure sensor.

Abstract: In one aspect, a pressure regulating valve assembly is provided. The valve assembly includes a housing having a fluid inlet and a fluid outlet, a sleeve positioned within the housing, and a spool at least partially positioned within the sleeve. The spool includes an outer surface having a shoulder, and the spool is configured to translate within the sleeve between a closed position and an open position. The valve assembly further includes a cap coupled to the sleeve and surrounding at least a portion of the spool, and the cap includes an inner surface with a flange extending therefrom. In the closed position the spool shoulder abuts against the cap flange to define a sealed metering edge. In the open position the spool shoulder is spaced from the cap flange to unseal the metering edge and define a metering window to facilitate fluid flow therethrough to the fluid outlet.

Abstract: A fuel control system includes a high pressure relief valve fluidly connected to a fuel pump outlet. The high pressure relief valve includes a closure and a nozzle. The closure has an opening and a locking notch defined by a circumferential wall. The nozzle has a base portion that is received within the opening and has a rim extending between a first surface and a second surface. The nozzle has a tab extending from the rim that is received within the locking notch.

Abstract: A bleed valve includes inlet and outlet housings, a hollow shaft defining a valve axis, and a full-area piston. The shaft includes a first end mounted to an inner diameter portion of the inlet housing and a second end mounted to an end cap of the outlet housing. The piston is slidably mounted to the shaft. A first chamber is defined between an upstream side of the piston and the inner diameter portion of the inlet housing. A second chamber is defined between a downstream side of the piston and the end cap of the outlet housing. An area of an upstream surface of the piston at an angle with respect to the valve axis is in fluid communication with the first chamber, and is substantially equal to an area of a downstream surface of the piston at an angle with respect to the valve axis and in fluid communication with the second chamber.

Abstract: A valve assembly includes a sleeve with an inlet and an outlet. A spool is slideably disposed within an interior of the sleeve and is movable along a spool movement axis defined by the sleeve between first and second positions such a flow area between the inlet and outlet is greater when the spool is in the second position than when the spool is in the first position. An aperture plate seats within the sleeve inlet and is axially adjacent to the spool. The aperture plate defines a core flow and a flow-directing aperture to center and straighten a fluid flow entering the sleeve inlet.

Abstract: A flexure includes a flexure body with an inner ring defining a main axis and an outer ring extending about the inner ring that is outboard of the inner ring with respect to the main axis. One or more flexure members having respective lengths that are greater than a radial offset distance defined between the inner ring and the outer ring connects the inner ring to the outer ring. A valve includes a valve member connected to a valve body by the flexure.

Abstract: A fluid metering valve includes a flow circuit defined by the valve and a valve member disposed in the flow circuit, the valve member having a sealing portion and configured to be moved by a solenoid between a closed position and one or more open positions. The valve includes a seat member defining one or more fluid outlets, the seat member configured to receive the sealing portion in the closed position to seal the fluid outlets, and an internal porting path defined through the sealing portion that is configured to fluidly connect a downstream side of the sealing portion with an upstream portion of the flow circuit in the closed position to reduce the effective pressure area of the valve member.

Abstract: A bleed valve for a gas turbine engine compressor has a valve body and a flapper. The valve body defines a flow path and includes a flapper seat. The flow path extends through the valve body. The flapper is pivotally connected to the valve body and is movable between a closed position and an open position. In the closed position the flapper seats against the flapper seat and blocks the flow path. In the open position the flapper is angled towards the valve body inlet such that fluid moving through the valve body exerts force on the flapper, urging the flapper towards the closed position.

Abstract: A bleed valve system includes a flow path defined between a system inlet and a system outlet. A pressure control mechanism is defined in the flow path downstream from the system inlet to selectively block fluid flow in the flow path. A pressure limiter is defined in the flow path downstream from the system inlet and upstream from the pressure control mechanism to block the flow path when the pressure at the system inlet is greater than the pressure capacity of the pressure control mechanism.

Abstract: Aspects of the disclosure are directed to an engine of an aircraft. Aspects of the disclosure include an inlet housing configured to receive core air of an engine, and at least one valve coupled to the inlet housing and configured to bleed the core air during a starting of the engine, where the at least one valve is housed within the engine.

Abstract: A multi-bend control circuit for fluid communication with an outlet port of a valve includes a first circuit leg extending in a first direction and a second circuit leg extending at an angle from the first circuit leg in a second direction. A third circuit leg extends at an angle from the second circuit leg in a third direction different from the second direction. A sense line tap is in fluid communication with at least one of the first, second or third legs.

Abstract: A bleed valve assembly includes a flow duct with an inlet and an outlet disposed downstream from the inlet. The outlet is smaller in cross-sectional area than a region of the flow duct disposed between the inlet and the outlet. A piston housing is disposed inside the flow duct between the inlet and the outlet so as to form an annular flow passage between the flow duct and the piston housing. The piston housing is axially aligned with a center axis of the flow duct. At least one rib extends between the flow duct and the piston housing. A sleeve piston is disposed inside the piston housing and is configured to extend downstream of the piston housing in a closed position. The sleeve piston comprises an outer wall that is at least the same in cross-sectional area as the outlet of the flow duct.

Abstract: A bleed valve includes a valve body, a first flapper body movable relative to the valve body between an open position and a closed position, and a second flapper body movable relative to the valve body between an open position and a closed position. A resilient member biases the first and second flapper bodies to the open position to vent bleed air. The first and second flapper bodies move to the closed position when a pressure load across the first and second flapper bodies exceeds a biasing force of the resilient member. A gas turbine engine is also disclosed.

Abstract: A bleed valve includes inlet and outlet housings, a hollow shaft defining a valve axis, and a full-area piston. The shaft includes a first end mounted to an inner diameter portion of the inlet housing and a second end mounted to an end cap of the outlet housing. The piston is slidably mounted to the shaft. A first chamber is defined between an upstream side of the piston and the inner diameter portion of the inlet housing. A second chamber is defined between a downstream side of the piston and the end cap of the outlet housing. An area of an upstream surface of the piston at an angle with respect to the valve axis is in fluid communication with the first chamber, and is substantially equal to an area of a downstream surface of the piston at an angle with respect to the valve axis and in fluid communication with the second chamber.

Abstract: A valve assembly includes a sleeve with an inlet and an outlet. A spool is slideably disposed within an interior of the sleeve and is movable along a spool movement axis defined by the sleeve between first and second positions such a flow area between the inlet and outlet is greater when the spool is in the second position than when the spool is in the first position. An aperture plate seats within the sleeve inlet and is axially adjacent to the spool. The aperture plate defines a core flow and a flow-directing aperture to center and straighten a fluid flow entering the sleeve inlet.

Abstract: In one aspect, a fluid flow disruptor is provided. The fluid flow disruptor includes a base flange having an outer diameter and an inner diameter, the base flange configured to couple to a valve, and a cap extending from the base flange. The cap includes a proximal end coupled to the base flange about the inner diameter, a distal end, and a sidewall extending between the proximal end and the distal end. At least one aperture is formed in the sidewall, and the fluid flow disruptor is configured to direct a fluid flowing in an axial direction to flow around the cap distal end, through the at least one aperture, and through the base flange inner diameter into the valve, to thereby increase a turbulence of the fluid to decrease an axial momentum load of the fluid acting on the valve.

Abstract: A valve has a sleeve with at least one outlet port in a radially outer surface. A piston is moveable within the sleeve along an axis. The piston has a lip on a radially outer portion extending forwardly to an axially forward most end and a recess radially inward from the lip with respect to an axis of the piston. A vane pump is also disclosed.