Abstract: Embodiments of the disclosure provide a shaft assembly including: a first shaft extending through a compressor and a turbine of the turbomachine; a second shaft coupled to the first shaft through a load coupling component; a generator mounted on the second shaft, wherein the turbine drives the generator; a plurality of mono-type low-loss bearings supporting the first and second shafts at the compressor, turbine, and generator; and a plurality of rotating blade structures within the compressor and the turbine of the turbomachine, wherein at least one of the plurality of rotating blade structures in the compressor includes a low-density material, and at least one of the plurality of rotating blade structures in the turbine includes the low-density material.

Abstract: Mechanical drive architectures can include a gas turbine having a compressor section, a turbine section, and a combustor section. A load compressor is driven by the gas turbine. A rotor shaft extends through the gas turbine and the load compressor. The rotor shaft has rotating blades arranged in a circumferential array to define a plurality of moving blade rows in the gas turbine and the load compressor. At least one of the rotating blades in one of the gas turbine and the load compressor includes a low-density material. Bearings support the rotor shaft within the gas turbine and the load compressor, wherein at least one of the bearings is a hybrid-type low-loss bearing.

Abstract: A turbine rotor disk includes a row of buckets secured about a radially outer periphery of the rotor disk, each bucket having an airfoil, a platform, a shank and a mounting portion, the mounting portion received in a radial slot formed in the rotor disk such that adjacent buckets in adjacent radial slots are separated by a rotor disk post located between adjacent mounting portions and a shank cavity between adjacent shanks, radially outward of the rotor disk post and radially inward of adjacent platforms. The shank cavity is substantially filled with at least one discrete thermal plug.

Abstract: Mechanical drive architectures can include a gas turbine having a compressor section, a turbine section, and a combustor section. A load compressor is driven by the gas turbine. A rotor shaft extends through the gas turbine and the load compressor. At least one of the rotating components in one of the gas turbine and the load compressor includes a low-density material. Bearings support the rotor shaft within the gas turbine and the load compressor, at least one of the bearings being a mono-type low-loss bearing.

Abstract: Power train architectures with hybrid-type low-loss bearings and low-density materials are disclosed. The gas turbine used in these architectures can include a compressor section, a turbine section, and a combustor section coupled to the compressor and turbine sections. A generator, coupled to the rotor shaft, is driven by the turbine section. The compressor section, the turbine section, and the generator include rotating components, at least one of which is a low-density material. Bearings support the rotor shaft within the compressor section, the turbine section and the generator, wherein at least one of the bearings is a hybrid-type low-loss bearing.

Abstract: Power train architectures with mono-type low-loss bearings and low-density materials are disclosed. The gas turbine used in these architectures can include a compressor section, a turbine section, and a combustor section. A generator, coupled to the rotor shaft, is driven by the turbine section. The compressor section, the turbine section, and the generator include rotating components, at least one of the rotating components in one of the compressor section, the turbine section, and the generator including a low-density material. Bearings support the rotor shaft within the compressor section, the turbine section and the generator, wherein at least one of the bearings is a mono-type low-loss bearing.

Abstract: A turbine bucket may generally include an airfoil formed from a metal-based material. The airfoil may include a base and a tip disposed opposite the base. The airfoil may also include a pressure side wall and a suction side wall extending between a leading edge and a trailing edge. Additionally, the turbine bucket may include a tip cap disposed between the pressure side wall and the suction side wall. The tip cap may be formed from a ceramic matrix composite material.

Abstract: An airfoil is provided and includes an airfoil body having a pressure surface extendable between radial ends and a fluid path in an airfoil interior defined therein. The pressure surface is formed to further define a passage by which coolant is deliverable from the fluid path in the airfoil interior, in a perimetric direction from the pressure surface for the purpose of cooling a portion on the surface of the radial end.

Abstract: A temperature gradient management arrangement for a turbine system includes a rotor comprising a rotor bore extending axially along the rotor. Also included is a secondary flow path comprising an inlet for a secondary airflow to flow to the rotor bore and an outlet disposed axially upstream of the inlet, relative to a main flow direction of the turbine system. Further included is a flow rate manipulator disposed proximate the outlet and configured to increase a flow rate of the secondary airflow during a first turbine system operating condition and to decrease the flow rate of the secondary airflow during a second turbine system operating condition.

Abstract: Embodiments of the present invention provide a S-EGR process that yields an exhaust stream that includes a relatively high concentration of a desirable gas and is also substantially oxygen-free. This desirable gas includes, but is not limited to: Carbon Dioxide (CO2), Nitrogen (N2), or Argon.

Abstract: The present invention provides a system and method of operating a combined-cycle powerplant at part-load without shutting down an HRSG and steam turbine. The present invention may apply to a powerplant operating in an open-cycle mode. The present invention may also apply to a powerplant operating in a closed-cycle mode.

Abstract: The present invention provides a system and method that yields an exhaust stream that includes a relatively high concentration of a desirable gas and is also substantially oxygen-free. This desirable gas includes, but is not limited to: Carbon Dioxide (CO2), Nitrogen (N2), or Argon. The present invention also provides a way to control the physical property of the exhaust stream.

Abstract: A turbine rotor disk includes a row of buckets secured about a radially outer periphery of the rotor disk, each bucket having an airfoil, a platform, a shank and a mounting portion, the mounting portion received in a radial slot formed in the rotor disk such that adjacent buckets in adjacent radial slots are separated by a rotor disk post located between adjacent mounting portions and a shank cavity between adjacent shanks, radially outward of the rotor disk post and radially inward of adjacent platforms. The shank cavity is substantially filled with at least one discrete thermal plug.

Abstract: A turbomachine includes a turbine section including a turbine inlet. A transition piece includes a transition piece inlet and a transition piece outlet. A ceramic matrix composite (CMC) bridge member links the transition piece outlet and the turbine inlet.

Abstract: A turbine bucket may generally include an airfoil formed from a metal-based material. The airfoil may include a base and a tip disposed opposite the base. The airfoil may also include a pressure side wall and a suction side wall extending between a leading edge and a trailing edge. Additionally, the turbine bucket may include a tip cap disposed between the pressure side wall and the suction side wall. The tip cap may be formed from a ceramic matrix composite material.

Abstract: A turbomachine includes a turbine section including a turbine inlet. A transition piece includes a transition piece inlet and a transition piece outlet. A ceramic matrix composite (CMC) bridge member links the transition piece outlet and the turbine inlet.

Abstract: An airfoil is provided and includes an airfoil body having a pressure surface extendable between radial ends and a fluid path in an airfoil interior defined therein. The pressure surface is formed to further define a passage by which coolant is deliverable from the fluid path in the airfoil interior, in a perimetric direction from the pressure surface for the purpose of cooling a portion on the surface of the radial end.

Abstract: A method and apparatus for a rotor assembly for gas turbine engine are provided. A first rotor blade including an airfoil, a platform, a shank, an internal cavity, and a dovetail is provided, wherein the airfoil extends radially outward from the platform, which includes a radially outer surface and a radially inner surface, the shank extends radially inward from the platform, and the dovetail extends from the shank, such that the internal cavity is defined by the airfoil, the platform, the shank, and the dovetail. The first rotor blade is coupled to a rotor shaft such that during engine operation, cooling air is channeled from the cavity through an impingement cooling circuit for impingement cooling the first rotor blade platform radially inner surface, and a second rotor blade is coupled to the rotor shaft such that a platform gap is defined between the first and second rotor blade platforms.

Abstract: In a gas turbine having a compressor discharge casing, a cooling circuit diverts compressor discharge air toward a high pressure packing (HPP) circuit. The cooling circuit includes an inlet pipe that receives compressor discharge air. One or several cooled cooling air pipes are in fluid communication with the inlet pipe via a pipe manifold, which distributes the discharge air across the cooled cooling air pipes. A seal is disposed upstream of an entrance to the HPP circuit to limit flow into the HPP circuit, and a second seal is disposed downstream of the HPP circuit at turbine wheelspace to limit ingestion and thus the purge flow air required. The circuit serves to reduce required purge flow in the HPP circuit so that an amount of compressor discharge air can be put back to the main flow path, thereby improving turbine performance.

Abstract: The cooling system for the airfoil includes forward and aft cooling circuits supplied with a cooling medium. Both circuits include serpentine passages. A central rib divides the forward and aft cooling circuits and includes an opening adjacent the airfoil tip providing a jet of the cooling medium from the forward cooling circuit for impingement against the aft portion of the tip cap. The tip cap also includes a thermal barrier coating along an outside surface thereof as well as on the seat for the tip cap, thereby lowering the tip cap metal temperature and thermally induced stress.