A gas turbine engine includes a fan section, a compressor section, and a turbine section. The fan section has a plurality of vane assemblies spaced circumferentially about an engine axis. The vane assemblies each include an airfoil extending between a leading edge and a trailing edge, a control rod extending through the airfoil, and a mechanism driven by the control rod to change the shape of the airfoil. A vane system for a gas turbine engine is also disclosed.

A gas turbine engine includes a fan section, a compressor section, and a turbine section. The fan section has a plurality of vane assemblies spaced circumferentially about an engine axis. The vane assemblies each include an airfoil extending between a leading edge and a trailing edge, a control rod extending through the airfoil, and a mechanism driven by the control rod to change the shape of the airfoil. A vane system for a gas turbine engine is also disclosed.

In one embodiment, a plant includes a combustor to burn fuel with oxygen from an inlet guide vane (IGV) to generate a gas for a gas turbine (GT), and a heat recovery steam generator to use an exhaust gas from GT to generate steam for a steam turbine (ST). An apparatus controls an IGV opening degree to a first degree and a GT output value to a value larger than a first value between GT start and ST start. The first value is an output value at which exhaust gas temperature can be kept at a first temperature that depends on ST metal temperature, when the IGV opening degree is the first degree. The apparatus increases the IGV opening degree from the first degree based on steam temperature or the GT output value, while the GT output value is controlled to the value larger than the first value.

The turboshaft engine for a rotorcraft includes a low pressure spool having a low pressure compressor and a low pressure turbine section, and a high pressure spool having a high pressure compressor and a high pressure turbine section. The spools are independently rotatable relative to one another. The low pressure compressor section includes a mixed flow rotor. A set of variable guide vanes (VGVs) are discposed upstream of each of the low pressure and high pressure compressors, the VGVs being configured to be independently operable relative to one another.

There is provided a system and a method for operating a multi-engine rotorcraft. When the rotorcraft is cruising in an asymmetric operating regime (AOR) at least one engine is an active engine and is operated in an active mode to provide motive power to the rotorcraft and at least one second engine is a standby engine and is operated in a standby mode to provide substantially no motive power to the rotorcraft, at least one of a power level of the at least one second engine is increased and at least one variable geometry mechanism of the at least one second engine is moved to shed any ice accumulation on the at least one second engine.

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 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.

An un-ducted turbofan engine defining a radial direction and an axial direction that includes a core engine, a fan, a plurality of variable outlet guide vanes, and a pitch change mechanism. Each of the plurality of variable outlet guide vanes are attached in a rotatable manner to the core engine of the un-ducted turbofan engine. The pitch change mechanism is positioned radially between the engine air flowpath and the plurality of variable outlet guide vanes and coupled to at least one variable outlet guide vane of the plurality of variable outlet guide vanes for changing a pitch of the at least one variable outlet guide vane.

An un-ducted turbofan engine defining a radial direction and an axial direction that includes a core engine, a fan, a plurality of variable outlet guide vanes, and a pitch change mechanism. Each of the plurality of variable outlet guide vanes are attached in a rotatable manner to the core engine of the un-ducted turbofan engine. The pitch change mechanism is positioned radially between the engine air flowpath and the plurality of variable outlet guide vanes and coupled to at least one variable outlet guide vane of the plurality of variable outlet guide vanes for changing a pitch of the at least one variable outlet guide vane.

An operation control device for a single shaft gas turbine selects an operation mode based on a load state of a power generator, and controls the turbine based on the operation mode. In a first operation mode, a rotational speed of the turbine is maintained within a first rotational speed range, and in a second operation mode, the rotational speed is maintained within a second rotational speed range set on a lower rotational speed side than the first rotational speed range. The second rotational speed range is set on the lower rotational speed side than the first rotational speed range with a first non-selection rotational speed range set therebetween.