A gas turbine engine with a compressor supplying compressed air. A combustor receives the compressed air and fuel and generates a flow of combusted gas. A turbine receives a core flow of the combusted gas to rotate a turbine rotor. A turbine inlet nozzle directs the combusted gas to the turbine rotor. Vanes are disposed in the turbine inlet nozzle and rotate to vary a flow area through which the core flow passes. The vanes adjust a pressure ratio of the gas turbine engine to compensate for changing operational requirements of the gas turbine engine by rotating to positions matching the changing operational requirements.

A disclosed gas turbine engine includes a gas generator section for generating a gas stream flow and a propulsor section for generating propulsive thrust as a mass flow rate of air through a bypass flow path. The propulsor section includes a fan driven by a power turbine through a speed reduction device at a second rotational speed lower than a first rotational speed of the power turbine. An Engine Unit Thrust Parameter (“EUTP”) defined as net engine thrust divided by a product of the mass flow rate of air through the bypass flow path, a tip diameter of the fan and the first rotational speed of the power turbine is between 0.05 and 0.13 during operation of the gas turbine engine.

A disclosed gas turbine engine includes a gas generator section for generating a gas stream flow and a propulsor section for generating propulsive thrust as a mass flow rate of air through a bypass flow path. The propulsor section includes a fan driven by a power turbine through a speed reduction device at a second rotational speed lower than a first rotational speed of the power turbine. An Engine Unit Thrust Parameter (“EUTP”) defined as net engine thrust divided by a product of the mass flow rate of air through the bypass flow path, a tip diameter of the fan and the first rotational speed of the power turbine is between 0.05 and 0.13 during operation of the gas turbine engine.

A system and method for predicting a remaining oil life of oil in a gearbox of an air turbine starter of a vehicle. The method includes generating a temperature data, generating an environmental data set by an environmental sensor, predicting a remaining oil life based on the temperature data set and the environmental data set and scheduling a maintenance event in response to the prediction of the remaining oil life.

A system and method for predicting a remaining oil life of oil in a gearbox of an air turbine starter of a vehicle. The method includes generating a temperature data, generating an environmental data set by an environmental sensor, predicting a remaining oil life based on the temperature data set and the environmental data set and scheduling a maintenance event in response to the prediction of the remaining oil life.

Provided is a startup control device for adjusting a startup schedule during startup of a power generation plant. This startup control device is provided with: a determining unit which, for a prescribed physical quantity that restricts the startup of the power generation plant, determines, on the basis of a predicted value of a physical quantity corresponding to the elapsed time from startup when the power generation plant has started up on the basis of a prescribed optimal startup schedule, and an observed value of the physical quantity acquired during the startup of the power generation plant, whether the observed value will exceed the predicted value; a speed adjusting unit which, if the determining unit determines that the observed value will exceed the predicted value, issues an instruction to decelerate the speed of progress of elapsed time from the startup in the optimal startup schedule; and a startup timer which progresses the elapsed time from the startup at a speed based on the instruction.

An engine control system may be configured to perform a method of controlling thermal bias in a turbomachine. An exemplary method may include determining a thermal bias-value for the turbomachine, and performing a cooling treatment based at least in part on the thermal bias-value. The thermal bias-value may include a difference between an upward temperature-value corresponding to a first one or more temperature measurements of an upward portion of the turbomachine and a downward temperature-value corresponding to a second one or more temperature measurements of a downward portion of the turbomachine. The cooling treatment may include at least one of: circulating air through at least a portion of the turbomachine, and rotating a shaft of the turbomachine with a motoring system.

An engine control system may be configured to perform a method of controlling thermal bias in a turbomachine. An exemplary method may include determining a thermal bias-value for the turbomachine, and performing a cooling treatment based at least in part on the thermal bias-value. The thermal bias-value may include a difference between an upward temperature-value corresponding to a first one or more temperature measurements of an upward portion of the turbomachine and a downward temperature-value corresponding to a second one or more temperature measurements of a downward portion of the turbomachine. The cooling treatment may include at least one of: circulating air through at least a portion of the turbomachine, and rotating a shaft of the turbomachine with a motoring system.

A method of operating a turbine engine that includes shutting down the turbine engine such that a rotational speed of the turbine engine decreases, and actuating a starter motor of the turbine engine at one of as the rotational speed of the turbine engine decreases or at a preset time after the turbine engine receives a full stop command such that residual heat is exhausted from the turbine engine.

A method of operating a turbine engine that includes shutting down the turbine engine such that a rotational speed of the turbine engine decreases, and actuating a starter motor of the turbine engine at one of as the rotational speed of the turbine engine decreases or at a preset time after the turbine engine receives a full stop command such that residual heat is exhausted from the turbine engine.