A system and method for adaptively controlling a cooldown cycle of an auxiliary power unit (APU) that is operating and rotating at a rotational speed includes reducing the rotational speed of the APU to a predetermined cooldown speed magnitude that ensures combustor inlet temperature has reached a predetermined temperature value, determining, based on one or more of operational parameters of the APU, when a lean blowout of the APU is either imminent or has occurred, and when a lean blowout is imminent or has occurred, varying one or more parameters associated with the shutdown/cooldown cycle.

An example embodiment of a turbine engine assembly includes a low spool including a low spool accessory drive gear driven by a low rotor shaft, a high spool including a high spool accessory drive gear driven by a high rotor shaft concentric around a portion of the low rotor shaft, and a differential gear assembly adapted to offtake power from rotation of one or both of the low spool and the high spool to drive one or more accessory loads. The differential gear assembly includes a differential bullgear and one or more idler gears each including a plurality of teeth meshed with the low spool accessory drive gear and the high spool accessory drive gear, and a bearing surface. The differential bull gear includes a plurality of teeth and a corresponding at least one bearing surface engaging with the bearing surface of each of the one or more idler gears. The plurality of teeth are adapted to mesh with an accessory drive system to transfer the power offtake and drive the one or more accessory loads.

A system of a hybrid aircraft includes a first gas turbine engine including a fan, a high speed spool, and a low spool motor configured to drive rotation of the fan. The system also includes a second gas turbine engine and a controller. The controller is operable to determine an operating mode of the hybrid aircraft, control the low spool motor to drive rotation of the fan of the first gas turbine engine responsive to a thrust command while the second gas turbine engine is driven by commanding fuel combustion based on the operating mode, and accelerate the high speed spool of the first gas turbine engine and command fuel combustion at the first gas turbine engine based on a transition of the operating mode to perform a starting operation of the first gas turbine engine.

A turbomachine, a computing system for a turbomachine, and a method for overspeed protection are provided. The turbomachine includes a first rotor assembly interdigitated with a second rotor assembly together operably coupled to a gear assembly. A plurality of sensors is configured to receive rotor state data indicative of one or more of a speed, geometric dimension, or capacitance, or change thereof, or rate of change thereof, relative to the first rotor assembly or the second rotor assembly. A controller executes operations including receiving rotor state data from the plurality of sensors; comparing rotor state data to one or more rotor state limits; and contacting one or more of the first rotor assembly or the second rotor assembly to a contact surface adjacent to the respective first rotor assembly or the second rotor assembly if the rotor state data exceeds the rotor state limit.

A gas turbine engine, includes: an engine core including a turbine, compressor, and shaft system connecting the turbine to the compressor, and forming a torque path therebetween. The shaft system is axially located by a thrust bearing located forward of the turbine, and the engine is configured, in the event of a shaft break which divides the shaft system into a front portion located by the thrust bearing and a rear portion unlocated by the thrust bearing, the rear portion is free to move axially rearwardly under a gas load. The engine further includes a shaft break detector having a forward speed sensor configured to measure a rotational speed of the front portion of the shaft system, and a rear microwave sensor configured to measure a rotational speed of the rear portion of the shaft system, wherein a shaft break can be detected based on differences in the measured speeds.

An apparatus for diagnosing and controlling the aerodynamic stability of a compressor and method there of are provided. The apparatus includes a measurement device (100), a signal processing device (200) and a control and execution device (300), wherein the measurement device (100) is configured to measure the pressure or velocity fluctuations of air flows in different positions inside a compressor in real time, and to transmit real-time measurement signals obtained from different positions to the signal processing device (200); the signal processing device (200) is configured to determine, according to the real-time measurement signals, a type and spatial distribution of instability precursor in the compressor, and to output corresponding control strategy signals to the control and execution device (300); and the control and execution device (300) executes, according to the received control strategy signals, corresponding control actions to regulate the stability of the compressor (S3).

A gas turbine engine in which a compressor, a combustor, and a turbine are arranged so as to be lined up along a rotating shaft includes: a casing that accommodates the compressor, the combustor, and the turbine; fuel pump units that are arranged at an outside of the casing, are lined up in a circumferential direction along an outer peripheral surface of the casing, and are connected in parallel; and a fuel supply pipe that collects fuel discharged from the fuel pump units and supplies the fuel to the combustor.

A system includes one or more sensors to detect unintended forward and reverse rotation of rotating machinery. The system also includes a monitoring system consisting of a processor, memory, display and communication interface. The processor receives signals from the sensors. The processor determines unintended rotation when the pattern of received signals match with the conditions defined in the processor. The processor generates a notification signal of “Unintended Rotation” on the display. The notification signal is also sent to the operator workstation to alert the operating personnel. The notification history is also stored in the system memory. The system is also configured to initiate automatic action to stop the unintended rotation and protect the machinery components from unintended rotation. The action may include closing the suction and discharge valve and starting the lubrication system to lube the bearings of the rotating machinery and the motor.

A method and device for detecting conditions conducive to the onset of pumping that can affect a low-pressure compressor of an aircraft turbine engine. The turbine engine including a high-pressure compressor. The method including measuring a speed variation of the aircraft and measuring a speed variation of the high-pressure compressor. The method including a preliminary step of measuring an altitude of the aircraft. The conditions conducive to the onset of pumping being detected when the following conditions are jointly obtained: (a) the speed variation measured over a predetermined time interval corresponds to an acceleration greater than a first positive threshold, (b) the measured speed variation corresponds to a deceleration less than a second negative threshold, and (c) the altitude is greater than a third predetermined threshold.

A turbocharger is used within a vehicle and includes an electronic actuator assembly. The electronic actuator assembly includes an actuator housing coupled to at least one of the turbine housing, the compressor housing, and the bearing housing, and an accelerometer coupled to the actuator housing. The accelerometer is adapted to detect vibration of at least one of the turbine housing, the compressor housing, the bearing housing, and the actuator housing thereby obtaining acceleration data of at least one of the turbine housing, the compressor housing, the bearing housing, and the actuator housing to determine rotational speed of the turbocharger shaft. Another embodiment includes a vibration detection assembly having an accelerometer coupled to a vehicle component and the vehicle component is one or more of a turbocharger, a valve assembly, an electronically driven compressor, and a turbocharger having an integral electric motor.