A method for selectively modulating bleed air used for cooling a downstream turbine section in a gas turbine engine. The method including: measuring an engine and/or aircraft performance parameter by an engine sensor device; comparing the engine and/or aircraft performance parameter to a performance threshold; determining a bleed trigger condition, if the engine and/or aircraft performance parameter crosses the performance threshold; determining a non-cooling condition, if the engine and/or aircraft performance parameter is below the performance threshold; actuating a flow control valve to an open position, in response to the bleed trigger condition, so that bleed air is extracted from the compressor section and flowed to the downstream turbine section; and terminating, in response to the non-cooling condition, the flow of the bleed air to the downstream turbine section of the engine by actuating the flow control valve to a closed position.

A method for selectively modulating bleed air used for cooling a downstream turbine section in a gas turbine engine. The method including: measuring an engine and/or aircraft performance parameter by an engine sensor device; comparing the engine and/or aircraft performance parameter to a performance threshold; determining a bleed trigger condition, if the engine and/or aircraft performance parameter crosses the performance threshold; determining a non-cooling condition, if the engine and/or aircraft performance parameter is below the performance threshold; actuating a flow control valve to an open position, in response to the bleed trigger condition, so that bleed air is extracted from the compressor section and flowed to the downstream turbine section; and terminating, in response to the non-cooling condition, the flow of the bleed air to the downstream turbine section of the engine by actuating the flow control valve to a closed position.

A dual volute turbocharger for use with an internal combustion engine includes a valve for controlling exhaust gas flow to a turbine housing interior of the dual volute turbocharger. The dual volute turbocharger also includes a first volute and a second volute each adapted for fluid communication with the internal combustion engine. The dual volute turbocharger further includes a wall separating the first and second volutes and a valve seat. The valve seat and the wall collectively define a valve cavity. The valve is movable between a closed position and an open position. The valve and the wall of the turbine housing collectively define a first cross-sectional flow area. The valve and the valve seat collectively define a second cross-sectional flow area. A method of controlling the valve of the dual volute turbocharger is also disclosed.

An auxiliary power unit (APU) control system for an aircraft is disclosed and includes an APU, an air inlet having an effective area, an air inlet door moveable to vary the effective area of the air inlet, an actuator configured to move the air inlet door into a set position, one or more processors, and a memory coupled to the one or more processors. The memory stores data comprising a database and program code that, when executed by the one or more processors, causes the APU control system to receive one or more ambient signals indicative of an air density value. The system also determines the effective area of the air inlet based on the air density value. The system is further caused to instruct the actuator to move the air inlet door into the set position.

An auxiliary power unit (APU) control system for an aircraft is disclosed and includes an APU, an air inlet having an effective area, an air inlet door moveable to vary the effective area of the air inlet, an actuator configured to move the air inlet door into a set position, one or more processors, and a memory coupled to the one or more processors. The memory stores data comprising a database and program code that, when executed by the one or more processors, causes the APU control system to receive one or more ambient signals indicative of an air density value. The system also determines the effective area of the air inlet based on the air density value. The system is further caused to instruct the actuator to move the air inlet door into the set position.

A gas turbine engine includes a fan section having a fan rotatable with a fan shaft and a turbomachinery section having a turbine and a turbomachine shaft rotatable with the turbine. A power gearbox is also provided mechanically coupled to both the fan shaft and the turbomachine shaft such that the fan shaft is rotatable by the turbomachine shaft across the power gearbox. A torque monitoring system includes a gearbox sensor operable with a gear of the power gearbox and a shaft sensor operable with at least one of the turbomachine shaft or the fan shaft. The torque monitoring system determines an angular position of the gear of the gearbox relative to at least one of the fan shaft or the turbomachine shaft using the gearbox sensor and the shaft sensor to determine a torque within the gas turbine engine.

A gas turbine engine includes a fan section having a fan rotatable with a fan shaft and a turbomachinery section having a turbine and a turbomachine shaft rotatable with the turbine. A power gearbox is also provided mechanically coupled to both the fan shaft and the turbomachine shaft such that the fan shaft is rotatable by the turbomachine shaft across the power gearbox. A torque monitoring system includes a gearbox sensor operable with a gear of the power gearbox and a shaft sensor operable with at least one of the turbomachine shaft or the fan shaft. The torque monitoring system determines an angular position of the gear of the gearbox relative to at least one of the fan shaft or the turbomachine shaft using the gearbox sensor and the shaft sensor to determine a torque within the gas turbine engine.

A system and method for determining performance of an engine is provided. The system includes two or more sensors configured in operable arrangement at two or more respective positions at a flowpath. The system includes one or more computing devices configured to perform operations, the operations include acquiring, via the two or more sensors, parameter sets each corresponding to two or more engine conditions different from one another, wherein each parameter set indicates a health condition at a respective location at the engine; comparing, via the computing device, the parameter sets to determine the respective health condition corresponding to the respective location at the engine; and generating, via the computing device, a health condition prediction based on the compared parameter sets.

A system and method for determining performance of an engine is provided. The system includes two or more sensors configured in operable arrangement at two or more respective positions at a flowpath. The system includes one or more computing devices configured to perform operations, the operations include acquiring, via the two or more sensors, parameter sets each corresponding to two or more engine conditions different from one another, wherein each parameter set indicates a health condition at a respective location at the engine; comparing, via the computing device, the parameter sets to determine the respective health condition corresponding to the respective location at the engine; and generating, via the computing device, a health condition prediction based on the compared parameter sets.

A maximum output creator is provided with: a temperature reception unit that receives an intake temperature, which is the temperature of air taken in by a compressor of a gas turbine; a change reception unit that receives the details of a change to a maximum opening degree in an intake quantity adjuster of the compressor; a basic maximum output computation unit that determines a basic maximum output of the gas turbine on the basis of the intake temperature received by the temperature reception unit; a coefficient creation unit that creates a maximum output correction coefficient for correcting the basic maximum output on the basis of the details of the change to the maximum opening degree received by the change reception unit and the intake temperature received by the temperature reception unit; and a maximum output correction unit that corrects the basic maximum output using the maximum output correction coefficient.