A gas turbine engine includes a fan and an engine core that includes a compressor, a combustor, and a turbine. The fan and the compressor include variable pitch geometry. The gas turbine engine further includes a control system configured to adjust the variable pitch geometry of the fan and the compressor to optimize a performance characteristic of the gas turbine engine.

A turbine system includes a compressor section, an inlet cooling system coupled upstream of the compressor section and configured to cool ambient air entering the compressor section, and a turbine section coupled in flow communication with the compressor section and including at least one hot gas path component. The system further includes a controller configured to receive feedback parameters indicative of a temperature of the at least one hot gas path component, estimate a remaining life of the at least one hot gas path component based on the received feedback parameters, determine a desired power output of the turbine system based on the estimated remaining life of the at least one hot gas path component and a cooling capacity of the inlet cooling system, and control operation of the turbine system to cause the turbine system to generate the desired power output.

An imaging device includes a plurality of electronic components, a phase change material, and a heat transfer structure. The plurality of electronic components is configured to collect data and have a predetermined temperature parameter. The plurality of electronic components is disposed within the phase change material. The phase change material has a first material phase and a second material phase. The phase change material has a first material phase and a second material phase. The phase change material is configured to absorb heat through changing from the first material phase to the second material phase. The heat transfer structure is disposed within the phase change material. The heat transfer structure is configured to conduct heat within the phase change material. The phase change material and the heat transfer structure are further configured to regulate a temperature of the electronic components below the predetermined temperature parameter.

A turbofan gas turbine engine having a bypass duct, and a bypass airflow measurement system. The bypass airflow measurement system comprises: at least one acoustic transmitter configured to transmit an acoustic waveform across the bypass duct of the gas turbine engine though which a bypass airflow passes to at least one acoustic receiver; where the at least one acoustic transmitter and the at least one acoustic receiver are located on an axial plane that is substantially perpendicular to the bypass flow. A method of measuring bypass airflow properties of a turbofan gas turbine engine is also described.

A method is provided for operating a hybrid-electric propulsion system having a first engine, a second engine, a first electric machine coupled to the first engine, and a second electric machine coupled to one of the first engine or the second engine. The method includes: receiving data indicative of a first engine operating parameter, a second engine operating parameter, or both; determining a first engine operating parameter margin, a second parameter operating margin, or both; determining a load share for the first engine, the second engine, or both, or between the first engine and the second engine based on the first engine operating parameter margin, the second engine operating parameter margin, or both; and transferring a first amount of power to or from the first electric machine and a second amount of power to or from the second electric machine in response to the determined load share.

A gas turbine system can estimate an amount of compressed air supplied to a combustor and limit a fuel amount according to the estimated compressed air amount. A control apparatus of the system includes a sensing unit to measure the turbine rotor speed; a compressed air amount estimation unit to estimate a change rate M.sub.R of an amount of compressed air produced by the compressor and supplied to the combustor, based on the measured turbine rotor speed; and a fuel amount control unit to control a fuel amount F.sub.C supplied to the combustor, based on the estimated change rate M.sub.R. The control apparatus can preemptively control the fuel amount in response to variations in the compressed air amount by a momentarily changing turbine rotor speed and can limit the turbine inlet temperature to below the maximum allowable temperature, to protect the turbine and/or combustor against fluctuations in compressed air amount.

The invention relates to an aircraft propulsion system, comprising a main transmission unit (12) and at least two turbojet engines connected to the main transmission unit (12), respectively a first turbojet engine (14a) and a second turbojet engine (14b), each turbojet engine comprising a free turbine (24a, 24b), characterized in that the first turbojet engine (14a) comprises a heat exchanger (30) configured to recover some of the thermal energy from the exhaust gas at the outlet of the free turbine, and in that the propulsion system comprises at least one computer (28a, 28b) configured to control the two turbojet engines and to limit the acceleration and the deceleration of the first turbojet engine (14a) when neither of the turbojet engines is broken down, in order to limit the reactor power transients at the heat exchanger (30).

A gas turbine engine system includes an engine component comprising ceramic matrix composite materials, at least one control system configured to control at least a temperature of the engine component, and a controller. The controller includes a degradation map stored therein. The degradation map includes degradation fields, each field defined by a unique range of temperatures and stresses of the component and correlated to different types of degradation of the component. The controller is configured to determine a first temperature and stress of the component and a first field based on the first temperature and stress, determine a second field different from the first and a second temperature and stress that would locate the component in the second field, and instruct the control system to change the temperature of the component from the first to the second temperature to locate the component in the second field.

A gas turbine control device includes a detection value acquisition unit that acquires a detection value of at least one of a supply amount of fuel, pressure of compressed air, and electric power generated by a generator; a flue gas temperature acquisition unit that acquires a flue gas temperature detection value; a combustion gas temperature estimate value calculation unit that calculates a combustion gas temperature estimate value based on the detection value; a correction term acquisition unit that calculates a correction term based on a ratio between the combustion gas temperature estimate value and the flue gas temperature detection value; a corrected combustion gas temperature estimate value calculation unit that corrects the combustion gas temperature estimate value using the correction term to calculate a corrected combustion gas temperature estimate value; and a gas turbine controller that controls the gas turbine based on the corrected combustion gas temperature estimate value.

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.