A method of assembling a gas turbine engine includes setting a build clearance at assembly in response to a running tip clearance defined with a cooled cooling air. A method of operating a gas turbine engine includes supplying a cooled cooling air to a high pressure turbine in response to an engine rotor speed.

A controller for a gas turbine is arranged to supply a load L. The gas turbine includes a fuel supply arranged to supply fuel at a fuel flow rate FF to a combustor, wherein the fuel supply includes a first fuel supply and a second fuel supply. The controller is arranged to determine one or more ratios R of one or more combustor operating parameters COP respectively at the load L to respective reference combustor operating parameters COPR at a reference load LR. The controller is further arranged to control a proportion P of the fuel flow rate FF supplied via the first fuel supply based, at least in part, on the determined one or more ratios R. A gas turbine with the controller and a method controls the gas turbine.

Embodiments of the present disclosure include methods, systems, and program products for controlling a machine. Methods according to the present disclosure can include: calculating, using a performance model of the machine, a set of inter-stage conditions of the machine corresponding to one of a set of input conditions and a set of output conditions during an operation of the machine, wherein the machine includes a turbine component having a fluid path therein traversing a plurality of turbine stages and a plurality of inter-stage positions; calibrating the performance model of the machine based on a difference between a predicted value in the performance model of the machine and one of the set of input conditions and the set of output conditions; and adjusting an operating parameter of the machine based on the calibrated performance model and the calculated set of inter-stage conditions of the machine.

An aspect includes a method of variable cycle compensation in a gas turbine engine. An electric component can be adjusted to compensate for a power change induced by an actuation system by operating the electric component as an electric motor to compensate for an increase in power absorption or a decrease in power production of a turbomachinery of the gas turbine engine. The actuation system is configured to adjust a variable cycle of the turbomachinery by adjusting power absorption or power production, and the electric component can be configured to add or subtract torque to a shaft of the gas turbine engine. The electric component can be operated as an electric generator to compensate for an increase in power production or a decrease in power absorption of the turbomachinery.

A turbomachine and method for operating a turbomachine comprising a first rotatable component and a second rotatable component each defining a rotatable speed mechanically independent of one another, and an electric machine electrically coupled to the first rotatable component and the second rotatable component such that a load level relative to the first rotatable component and the second rotatable component is adjustable is generally provided. The method includes adjusting a first load at a first rotor assembly of the electric machine electrically coupled to the first rotatable component such that a first speed of the first rotatable component is increased or decreased based on an engine condition and the first load; adjusting a second load at a second rotor assembly of the electric machine electrically coupled to the second rotatable component such that a second speed of the second rotatable component is decreased or increased based on the engine condition and the second load; and transferring electrical energy generated from at least one of the first rotatable component or the second rotatable component.

Aspects of the disclosure are directed to systems and methods for receiving operating state parameters associated with an operative state of an aircraft, determining a clearance value between a first structure of the engine and a second structure of the engine, where the clearance value is determined based on the operating state parameters and a passive clearance model that includes a specification of an uncertainty in the clearance value, determining that the clearance value deviates from a clearance target in an amount that is greater than a threshold, and engaging an active clearance control (ACC) mechanism based on the deviation.

A method for operating a gas turbine plant with gaseous fuel, which is conveyed to the gas turbine plant through a gas line, burnt in a combustion chamber and then supplied to a gas turbine. At least one valve for controlling the flow of the fuel to the combustion chamber is installed in the gas line, a critical opening position being defined for the valve. To provide an improved method for operating a gas turbine plant in which the power of the gas turbine plant is kept at a maximum for as long as possible in the event of insufficient pressure in the gas line, a temperature of the fuel in the gas line is reduced when the valve is about to exceed the critical opening position.

The invention aims to shorten the time required for start-up and prevent excessive increases in the heat loads on turbine blades. A humid air turbine includes a compressor; a combustor; a turbine; an exhaust heat recovery unit for recovering the heat of turbine exhaust gas to generate high-temperature moisture; a fuel supply system having a fuel flow rate control valve; an exhaust temperature acquiring unit for acquiring a temperature of the exhaust discharged while the turbine is driven; a combustion gas moisture ratio calculating section for calculating a ratio of moisture contained in combustion gas; an exhaust temperature upper limit calculating section for setting an exhaust temperature upper limit based on the combustion gas moisture ratio and the pressure ratio; an exhaust temperature difference calculating section for calculating the difference between the exhaust temperature upper limit and the exhaust temperature; a fuel flow rate command value calculating section for calculating a fuel flow rate command value using the exhaust temperature difference; and a control command value output section for outputting a command signal to the fuel flow rate control valve based on the command value selected by a fuel flow rate command value selecting section.

A design method of aero-engine on-line optimization and multivariable control based on model prediction control realizes aero-engine multivariable control and on-line optimization according to thrust, rotational speed and other needs under the condition of meeting constraints. The first part is a prediction model acquisition layer that continuously establishes a small deviation linear model of an aero-engine near different steady state points based on the actual operating state of the aero-engine in each control cycle and external environment parameters and that supplies model parameters to a controller; and the second part is a control law decision-making layer which is a closed loop structure that consists of a model prediction controller and an external output feedback. The model prediction controller determines the output of the controller at next moment by solving a linear optimization problem according to an engine model in the current state, a control instruction and relevant constraints.

Systems and methods axe disclosed herein that generally involve a double pinch criterion for optimization of regenerative Rankine cycles. In some embodiments, operating variables such as bleed extraction pressure and bleed flow rate are selected such that a double pinch is obtained in a feedwater heater, thereby improving the efficiency of the Rankine cycle. In particular, a first pinch point is obtained at the onset of condensation of the bleed and a second pinch point is obtained at the exit of the bleed from the feedwater heater. The minimal approach temperature at the first pinch point can be approximately equal to the minimal approach temperature at the second pinch point. Systems that employ regenerative Rankine cycles, methods of operating such systems, and methods of optimizing the operation of such systems are disclosed herein in connection with the double pinch criterion.