Abstract: A method of controlling a vapour-compression system for circulating a working fluid. The vapour-compression system comprises a compressor, an expansion device and an evaporator configured to facilitate heat transfer from a thermal source into the working fluid. The method comprises: determining or receiving a cooling demand, the cooling demand being associated with a demand to cool the thermal source; determining a preliminary thermofluidic property objective value based on the cooling demand; determining a final thermofluidic property objective value based on the preliminary thermofluidic property objective value and one or more thermofluidic property objective value thresholds, wherein the final thermofluidic property objective value relates to a target thermofluidic property of the working fluid at a control location within the vapour-compression system; and controlling at least one of the compressor and the expansion device based on the final thermofluidic property objective value.

Abstract: A method of operating a gas turbine engine having a spool includes executing, by a controller, a pre-shutdown procedure. The pre-shutdown procedure includes: determining a parameter associated with a thermal condition of the gas turbine engine; and calculating an idle period for an idle rotation operation to be performed in a shutdown procedure. Calculation of the idle period is based on the determined parameter.

Abstract: A method of operating a gas turbine engine having a spool includes executing, by a controller, a shutdown procedure. The shutdown procedure includes: performing an idle rotation operation; determining a parameter associated with a thermal condition of the gas turbine engine while the idle rotation operation is performed; determining, based on the determined parameter, whether the gas turbine engine has met a pre-determined criterion corresponding to a thermally stabilised condition; and terminating the idle rotation operation in response to a determination that the gas turbine engine has met the pre-determined criterion.

Abstract: Disclosed is a computer-implemented method for controlling an engine system of a vehicle comprising: determining an operating condition of the vehicle; determining one or more contextual conditions relevant to the vehicle; selecting, based upon both the determined operating condition and the determined one or more contextual conditions, a control profile for the engine system from a directory comprising a plurality of control profiles having different control characteristics; applying the selected control profile to a controller of the engine system; and controlling the engine system with the controller in accordance with the selected control profile. Also disclosed are an engine control system, a gas turbine engine, and an aircraft.

Abstract: There is disclosed a gas turbine engine comprising: an electrically-powered motor configured to rotate a driven spool of the gas turbine engine; a primary controller configured to conduct a primary function using the motor; and a bow controller configured to selectively control the motor to perform a rotor bow mitigation operation in which the motor drives the driven spool to rotate to mitigate a non-uniform thermal distribution in a rotor of a spool of the gas turbine engine.

Abstract: There is provided a method of starting a gas turbine engine, comprising: selecting a baseline starting procedure of the gas turbine engine based on environmental data; receiving condition information for the gas turbine engine and/or for a starting system of the gas turbine engine, the condition information comprising at least one of: health information for the gas turbine engine and/or the starting system; maintenance information for the gas turbine engine and/or the starting system; and operation information relating to an expected future usage of the gas turbine engine. The method further comprises determining a predicted degradation profile for the gas turbine engine and/or the starting system based on the condition information; determining a starting procedure of the gas turbine engine by adapting the baseline starting procedure based on the predicted degradation profile; and controlling the gas turbine engine and/or the starting system according to the determined starting procedure.

Abstract: A computer-implemented method of enabling optimisation of derate for a propulsion system of a vehicle, the method comprising: determining a derate for the propulsion system of the vehicle using: an algorithm; a vehicle model defining path constraints for the vehicle through space; a propulsion system model defining parameters of the propulsion system; an objective function defining one or more objectives; and controlling output of the determined derate.

Abstract: There is provided a method of starting a gas turbine engine, comprising: selecting a baseline starting procedure of the gas turbine engine based on environmental data; receiving condition information for the gas turbine engine and/or for a starting system of the gas turbine engine, the condition information comprising at least one of: health information for the gas turbine engine and/or the starting system; maintenance information for the gas turbine engine and/or the starting system; and operation information relating to an expected future usage of the gas turbine engine. The method further comprises determining a predicted degradation profile for the gas turbine engine and/or the starting system based on the condition information; determining a starting procedure of the gas turbine engine by adapting the baseline starting procedure based on the predicted degradation profile; and controlling the gas turbine engine and/or the starting system according to the determined starting procedure.

Abstract: A method of operating a gas turbine engine having a spool includes executing, by a controller, a shutdown procedure. The shutdown procedure includes: performing an idle rotation operation; determining a parameter associated with a thermal condition of the gas turbine engine while the idle rotation operation is performed; determining, based on the determined parameter, whether the gas turbine engine has met a pre-determined criterion corresponding to a thermally stabilised condition; and terminating the idle rotation operation in response to a determination that the gas turbine engine has met the pre-determined criterion.

Abstract: A method of operating a gas turbine engine having a spool includes executing, by a controller, a pre-shutdown procedure. The pre-shutdown procedure includes: determining a parameter associated with a thermal condition of the gas turbine engine; and calculating an idle period for an idle rotation operation to be performed in a shutdown procedure. Calculation of the idle period is based on the determined parameter.

Abstract: There is provided a method of starting a gas turbine engine, comprising: selecting a baseline starting procedure of the gas turbine engine based on environmental data; receiving condition information for the gas turbine engine and/or for a starting system of the gas turbine engine, the condition information comprising at least one of: health information for the gas turbine engine and/or the starting system; maintenance information for the gas turbine engine and/or the starting system; and operation information relating to an expected future usage of the gas turbine engine. The method further comprises determining a predicted degradation profile for the gas turbine engine and/or the starting system based on the condition information; determining a starting procedure of the gas turbine engine by adapting the baseline starting procedure based on the predicted degradation profile; and controlling the gas turbine engine and/or the starting system according to the determined starting procedure.

Abstract: There is disclosed a gas turbine engine comprising: an electrically-powered motor configured to rotate a driven spool of the gas turbine engine; a primary controller configured to conduct a primary function using the motor; and a bow controller configured to selectively control the motor to perform a rotor bow mitigation operation in which the motor drives the driven spool to rotate to mitigate a non-uniform thermal distribution in a rotor of a spool of the gas turbine engine.

Abstract: Described herein is a method of monitoring a condition of a component of a gas turbine engine, comprising: obtaining, with a non-contact monitoring sensor, monitoring data, wherein a portion of the monitoring data relates to the condition of the component of the gas turbine engine; obtaining, using a position sensor, positional data relating to the component's position; communicating the monitoring data and the positional data to a processing module, and analysing, using the processing module, the monitoring data and positional data to determine the portion of the monitoring data which relates to the component and determine a condition of the component. Also described herein is a system for monitoring and a gas turbine engine comprising the system.

Abstract: Disclosed is a computer-implemented method for controlling an engine system of a vehicle comprising: determining an operating condition of the vehicle; determining one or more contextual conditions relevant to the vehicle; selecting, based upon both the determined operating condition and the determined one or more contextual conditions, a control profile for the engine system from a directory comprising a plurality of control profiles having different control characteristics; applying the selected control profile to a controller of the engine system; and controlling the engine system with the controller in accordance with the selected control profile. Also disclosed are an engine control system, a gas turbine engine, and an aircraft.

Abstract: A control system of a gas turbine engine is provided. The engine has a fuel flow metering valve which regulates a fuel flow to the engine, and one or more variable geometry components which are movable between different set points to vary an operating configuration of the engine. The control system has an engine fuel control sub-system which provides a fuel flow demand signal for controlling the fuel flow metering valve. The control system further has a variable geometry control sub-system which determines current set points to be adopted by the variable geometry components given the current engine operating condition in order to comply with one or more engine constraints. The control system further has an optimiser that receives the current set points and determines adjusted values of the set points which optimise, while complying with the engine constraints, an objective function modelling a performance characteristic of the engine, the objective function adapting to change in engine performance with time.

Abstract: A computer-implemented method of enabling optimisation of trajectory for a vehicle, the method comprising: determining a trajectory for the vehicle using: an algorithm; a vehicle model defining path constraints for the vehicle through space; a propulsion system model defining parameters of a propulsion system of the vehicle; an objective function defining one or more objectives; and controlling output of the determined trajectory.

Abstract: A computer-implemented method of enabling optimisation of derate for a propulsion system of a vehicle, the method comprising: determining a derate for the propulsion system of the vehicle using: an algorithm; a vehicle model defining path constraints for the vehicle through space; a propulsion system model defining parameters of the propulsion system; an objective function defining one or more objectives; and controlling output of the determined derate.

Abstract: A method of optimizing the operation of a fleet of gas turbine engines is provided. The method comprises the steps of: (a) measuring respective values for plural control actuator settings within each of the gas turbine engines; (b) deriving, based on data external to the operation of the gas turbine engines, a desired performance modification of the gas turbine engines; (c) determining, based on the measured control actuator settings, one or more respective trim signals for varying selected of the control actuator settings to achieve the desired performance modification; and (d) transmitting the trim signals to respective electronic controllers of the engines to vary the selected control actuator settings accordingly.

Abstract: A computer-implemented method of optimizing the performance of a reconfigurable power system is provided. The method comprises the steps of: receiving an operating profile for the power system; partitioning the operating profile into a plurality of sub-phases; performing a coarse optimisation routine of the power system over each sub-phase of the operating profile to derive a respective coarsely optimised configuration of the power system; performing a fine optimisation routine of each coarsely optimised configuration over its respective sub-phase of the operating profile to derive a respective finely optimised configuration for that sub-phase; and defining settings of the power system to implement the finely optimised configurations thereon.

Abstract: A control system of a gas turbine engine is provided. The engine has a fuel flow metering valve which regulates a fuel flow to the engine, and one or more variable geometry components which are movable between different set points to vary an operating configuration of the engine. The control system has an engine fuel control sub-system which provides a fuel flow demand signal for controlling the fuel flow metering valve. The control system further has a variable geometry control sub-system which determines current set points to be adopted by the variable geometry components given the current engine operating condition in order to comply with one or more engine constraints. The control system further has an optimiser that receives the current set points and determines adjusted values of the set points which optimise, while complying with the engine constraints, an objective function modelling a performance characteristic of the engine, the objective function adapting to change in engine performance with time.