A continuous slag processing system includes a rotating parallel disc pump, coupled to a motor and a brake. The rotating parallel disc pump includes opposing discs coupled to a shaft, an outlet configured to continuously receive a fluid at a first pressure, and an inlet configured to continuously discharge the fluid at a second pressure less than the first pressure. The rotating parallel disc pump is configurable in a reverse-acting pump mode and a letdown turbine mode. The motor is configured to drive the opposing discs about the shaft and against a flow of the fluid to control a difference between the first pressure and the second pressure in the reverse-acting pump mode. The brake is configured to resist rotation of the opposing discs about the shaft to control the difference between the first pressure and the second pressure in the letdown turbine mode.

A gas turbine engine including a compressor has a first compressor section and a second compressor section, a combustor fluidly connected to the compressor, and a turbine fluidly connected to the combustor. The turbine includes a first turbine section and a second turbine section. A first shaft connects the first compressor section and the first turbine section. A second shaft connects the second compressor section and the second turbine section. A fan is connected to the first shaft via a geared architecture. The first shaft includes at least one magnetic section. An electromagnet is disposed radially outward of the first shaft at an axial location of the at least one magnetic section, relative to an axis defined by the gas turbine engine.

Techniques are described for using an electrical motor to slow down or stop a propulsor during an operation mode where the engine is to be otherwise running but the speed of the propulsor should be low or the propulsor should be stopped.

An operation method of a turbine fracturing device and a turbine fracturing device are provided. The turbine fracturing device includes a turbine engine, a speed reducer, a brake mechanism, and a fracturing pump, the method includes: driving, by the turbine engine, the fracturing pump to perform a fracturing operation through the speed reducer so as to keep the fracturing pump in an operating state, the fracturing pump being configured to suck fluid of a first pressure and discharge fluid of a second pressure, the second pressure being greater than the first pressure; and in response to an idling instruction, the turbine engine entering an idling state and triggering a brake operation so as to keep the fracturing pump in a non-operating state.

A shaft failure protection system includes an engine core comprising a turbine, a compressor, and a shaft connecting the turbine and compressor; a first braking element connected to a rotating part of the turbine; and a second braking element connected to a static part of the turbine. The first and second braking elements are arranged at an axial distance under normal operating conditions and configured to contact each other in case of a failure of the shaft and an associated axial displacement of the rotating part. The first braking element includes a first friction material and the second braking element comprises a second friction material, wherein the first and second friction materials each comprise a carbon-silica composite or a carbon-fibre-reinforced carbon. Upon shaft failure and associated axial displacement of the rotating part, the first and second friction materials contact each other to reduce speed of the rotating part.

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.

An operation method of a turbine fracturing device and a turbine fracturing device are provided. The turbine fracturing device includes a turbine engine, a speed reducer, a brake mechanism, and a fracturing pump, the method includes: driving, by the turbine engine, the fracturing pump to perform a fracturing operation through the speed reducer so as to keep the fracturing pump in an operating state, the fracturing pump being configured to suck fluid of a first pressure and discharge fluid of a second pressure, the second pressure being greater than the first pressure; and in response to an idling instruction, the turbine engine entering an idling state and triggering a brake operation so as to keep the fracturing pump in a non-operating state.

An engine system of an aircraft includes a gas turbine engine comprising at least one spool and at least one electric machine operably coupled with the at least one spool. A controller is configured to detect if the at least one spool of the gas turbine engine is in or is approaching an overspeed condition and apply a load to the at least one spool via the at least one electric machine.

A compressor surge control system includes a rotor system with at least one compressor section and at least one turbine section operably coupled to a shaft. The compressor surge control system also includes one or more rotor system sensors configured to collect a plurality of sensor data from the rotor system, an electric motor operably coupled to the rotor system, and a controller. The controller is operable to monitor the one or more rotor system sensors while the rotor system is rotating. The controller determines whether the plurality of sensor data from the one or more rotor system sensors is indicative of an early-stage compressor surge oscillation. A surge control torque is determined to diminish the early-stage compressor surge oscillation of the rotor system. The electric motor is commanded to apply the surge control torque to the rotor system.

Embodiments of systems and methods for operating a gas turbine engine defining a bowed rotor condition are generally provided. The systems and methods include rotating a rotor assembly defining a bowed rotor condition from approximately zero revolutions per minute (RPM) to within a bowed rotor mitigation speed range, in which the bowed rotor mitigation speed range is defined by a lower speed limit greater than zero RPM and an upper speed limit less than or equal to an idle speed condition of the gas turbine engine; applying a load at the rotor assembly via an energy storage device; adjusting the load to limit rotational speed or acceleration of the rotor assembly to within the bowed rotor mitigation speed range for a period of time; and removing the load to enable rotation of the rotor assembly to the idle speed condition following the period of time.