A turbine for a turbomachine of longitudinal axis including an alternating arrangement of annular rows of movable blades and of fixed blades and a radially inner annular cavity formed radially inside the movable and fixed blades, and a supply circuit for supplying cooling air to the inner annular cavity, the downstream end of the supply circuit comprising an inner annular row of orifices and an outer annular row of orifices opening into the radially inner annular cavity. The turbine may also include means for controlling the flow rate of supply air to the orifices of the inner and outer annular rows of orifices.

A gas turbine engine comprises a main compressor section having a high pressure compressor with a downstream most end, and more upstream locations. A turbine section has a high pressure turbine. A first tap taps air from at least one of the more upstream locations in the main compressor section, passes the tapped air through a heat exchanger and then to a cooling compressor. The cooling compressor compresses air downstream of the heat exchanger. A second tap taps air from a location closer to the downstream most end than the location(s) of the first tap. The first and second tap mix together and are delivered into the high pressure turbine. An intercooling system for a gas turbine engine is also disclosed.

A flow transfer apparatus for transferring cooling flow from a primary gas flowpath to a turbine rotor. The apparatus includes a first supply plenum communicating with the primary gas flowpath and first inducers, the first inducers configured to accelerate a first fluid flow from the first supply plenum and discharge it toward the rotor with a tangential velocity; a second supply plenum communicating with the primary gas flowpath and second inducers, the second inducers configured to accelerate a second fluid flow from the second supply plenum towards the rotor with a tangential velocity; and a cooling modulation valve operable to selectively permit or block the second fluid flow from the primary gas flowpath to the second supply plenum. The valve includes a flow control structure disposed in the primary gas flowpath and an actuation structure extending to a location radially outside of a casing defining the primary gas flowpath.

A mid-turbine frame (MTF) for a jet engine is disclosed and comprises a duct that extends between a high pressure turbine (HPT) and a low pressure turbine (LPT), the duct comprising a plurality of segments that together form an outer annular structure and an inner annular structure, the inner annular structure situated radially inward of the outer annular structure, and/or a plurality of vanes that extend radially outward from the inner annular structure toward the outer annular structure, each vane comprising a channel. Each segment may be coupled to an adjacent segment by a seal.

In a featured embodiment, a gas turbine engine has a compressor section having a downstream rotor and a diffuser downstream of the compressor section. A combustor receives air downstream of the diffuser. A turbine section has at least one component to be cooled. A conduit is spaced from the diffuser and defines a cooling airflow path. The cooling airflow path is separate from an airflow downstream the diffuser, and passing to the combustor. The conduit passes cooling air to the component to be cooled.

A gas turbine engine comprises a main compressor section having a high pressure compressor with a downstream most end, and more upstream locations. A turbine section has a high pressure turbine. A first tap taps air from at least one of the more upstream locations in the main compressor section, passes the tapped air through a heat exchanger and then to a cooling compressor. The cooling compressor compresses air downstream of the heat exchanger. A second tap taps air from a location closer to the downstream most end than the location(s) of the first tap. The first and second tap mix together and are delivered into the high pressure turbine. An intercooling system for a gas turbine engine is also disclosed.

A system and method for active draft control through a combined cycle power plant (CCPP) can initiate a CCPP shutdown, activate the recirculated exhaust gas (REG) system for the turbomachine; measure a HRSG airflow through the HRSG; communicate the HRSG airflow to a controller configured to condition a control signal; and adjust a recirculated exhaust gas volume in accordance with the control signal.

A flow transfer apparatus for transferring cooling flow from a primary gas flowpath to a turbine rotor. The apparatus includes a first supply plenum communicating with the primary gas flowpath and first inducers, the first inducers configured to accelerate a first fluid flow from the first supply plenum and discharge it toward the rotor with a tangential velocity; a second supply plenum communicating with the primary gas flowpath and second inducers, the second inducers configured to accelerate a second fluid flow from the second supply plenum towards the rotor with a tangential velocity; and a cooling modulation valve operable to selectively permit or block the second fluid flow from the primary gas flowpath to the second supply plenum. The valve includes a flow control structure disposed in the primary gas flowpath and an actuation structure extending to a location radially outside of a casing defining the primary gas flowpath.

A gas turbine engine has a core engine including: a compressor, combustion equipment which receives compressed air from the compressor, a circumferential row of nozzle guide vanes, and a turbine. The nozzle guide vanes defines a throat receiving hot working gases from the combustion equipment into the turbine. The gas turbine engine further has an air system which is switchably operable between an on-position which opens a diversion pathway along which a portion of the compressed air exiting the compressor bypasses the combustion equipment to join the hot working gases at re-entry holes located between the nozzle guide vanes and a rotor at the front of the turbine, thereby increasing the semi-dimensional mass flow (T30).sup.0.5/(P30) of the core engine at the exit of the compressor, and an off-position which closes the diversion pathway, thereby decreasing the semi-dimensional mass flow of the core engine at the exit of the compressor.

A gas turbine cooling system includes: a cooling air line that guides compressed air; a cooler that cools the compressed air; a flow rate adjuster that adjusts the flow rate of the cooling air; and a control device. The control device includes: a load change determination unit that determines whether a load indicated by a load command of the gas turbine has changed; a first command generation section that generates a first command indicating such an operation amount of the flow rate adjuster as allows the flow rate of the cooling air to meet a target flow rate; and a second command generation section that, when it is determined that the load indicated by the load command has changed, generates a second command indicating such an operation amount of the flow rate adjuster as allows a change-adapted flow rate higher than the target flow rate to be met.