Abstract: A helical seal system includes a first component, and a second component rotatable relative to the first component. The second component extends from a high pressure portion to a low pressure portion through an intermediate portion. A helical seal is provided on the intermediate portion of the second component. The helical seal includes at least one thread component having a pitch that is configured and disposed to draw fluids from the low pressure portion toward the high pressure portion when the second component is rotated.

Abstract: A system for passively varying an axial position of an inner casing of a gas turbine pursuant to changing pressure in a flowpath during transient engine operation. The system may include: a connection assembly slidably connecting the inner casing to the outer casing for axial movement of the inner casing between a first position and a second position; means for pressurizing the annulus relative to a flowpath pressure; biasing means for axially preloading the inner casing toward the first position; and an inner casing receiving surface configured to receive a pressure in the annulus for axially loading the inner casing in opposition to the axial preload of the biasing means.

Abstract: Thermal control is provided for a gas turbine casing by supplying thermal control gas from a compressor to a space between an outer casing and an inner casing, and transferring the thermal control gas from the space through the opening in the inner casing via a plurality of holes defined through a plate attached to an outer surface of the inner casing. The holes are arranged with a predetermined non-uniform distribution corresponding to a desired preferential impingement pattern for providing non-uniform heat transfer. A gas turbine thermal control assembly includes structure providing preferential heat transfer from the inner casing during operation of the gas turbine via a thermal control gas flow path from radially outside of the inner casing into the interior of the gas turbine.

Abstract: A device for directing gas impingement to an inner casing of a gas turbine may include a plate configured for attachment to the outer surface of the inner casing. The plate has a first surface opposing the inner casing when the plate is attached to an area of the inner casing and a second surface opposite the first surface. The plate defines a plurality of holes through the plate from the first surface to the second surface. The holes are arranged with a predetermined non-uniform distribution in the plate corresponding to a desired preferential impingement pattern for providing non-uniform heat transfer from the area during operation of the gas turbine so as to control temperature of the inner casing across the area. Various options and modifications are possible. Related gas turbine assemblies are also disclosed.

Abstract: In one embodiment, a system includes a fuel nozzle that includes a fuel injector that includes a fuel port and a premixer tube. The premixer tube includes a wall disposed about a central passage, multiple air ports extending through the wall into the central passage, and a catalytic region. The catalytic region includes a catalyst, disposed inside the wall along the central passage, configured to increase a reaction of fuel and air.

Abstract: A system includes an inducer assembly configured to receive a fluid flow from compressor fluid source and to turn the fluid flow in a substantially circumferential direction into the exit cavity. The inducer assembly includes multiple flow passages. Each flow passage includes an inlet configured to receive the fluid flow and an outlet configured to discharge the fluid flow into the exit cavity, and each flow passage is defined by a first wall portion and a second wall portion extending between the inlet and the outlet. The first wall portion includes a first surface adjacent the outlet that extends into the exit cavity.

Abstract: A thermal isolation apparatus is provided and includes an annular casing surrounding a turbine bucket stage and defining an annular recess from an interior facing surface thereof, an annular shroud disposed within the casing to provide for a predefined clearance about rotating bucket tips of the turbine bucket stage, the shroud including an annular main member and an annular flange extending from an outwardly facing surface of the main member and being sized to fit within the recess and a thermal barrier formed of porous material, which is interposed between opposing surfaces of the casing and the flange within the recess.

Abstract: A bucket assembly cooling apparatus is provided. The bucket assembly includes a platform, an airfoil, and a shank. The airfoil may extend radially outward from the platform. The shank may extend radially inward from the platform. The shank may include a pressure side sidewall, a suction side sidewall, an upstream sidewall, and a downstream sidewall. The sidewalls may at least partially define a cooling circuit. The cooling circuit may be configured to receive a cooling medium and provide the cooling medium to the airfoil. The upstream sidewall may at least partially define an interior cooling passage and at least partially define an exterior ingestion zone. The cooling passage may be configured to provide a portion of the cooling medium from the cooling circuit to the ingestion zone of an adjacent bucket assembly.

Abstract: A fuel nozzle for use with a combustion chamber defined within a gas turbine engine and a method for assembling the same are provided. The fuel nozzle includes a swirler assembly and a burner tube that is coupled to a support flange in a detachable manner such that an inner surface of the burner tube circumscribes an outer surface of the swirler assembly during fuel nozzle operation.

Abstract: A turbomachine includes an inner casing component having a first end that extends to a second end and a seal member. An outer casing component is coupled to the inner casing component. The annular outer casing component includes a first end portion that extends to a second end portion and a seal element that aligns with the seal member of the annular inner casing component to form a seal passage. A seal is arranged in the seal passage. The seal includes a first end section that extends to a second end section through an intermediate zone. The first end section includes a recessed portion and the second end section includes a connecting portion. The connecting portion is configured and disposed to nest within the recessed portion to form a substantially continuous seal.

Abstract: A system is provided with a turbine exhaust strut configured to provide a bi-directional airflow. The turbine exhaust strut includes a first portion having a first flow passage configured to flow a fluid in a first direction between inner and outer exhaust walls of a turbine exhaust section, and a second portion having a second flow passage configured to flow the fluid in a second direction between the inner and outer exhaust walls of the turbine exhaust section. Furthermore, the first and second directions are opposite from one another.

Abstract: A method for assembling a rotor assembly for use with a turbine engine. The method includes providing at least two rotor blades that each include a shank extending between a dovetail and a platform. The shank includes at least one cover plate that extends inwardly from the platform towards the dovetail. An airfoil extends outwardly from the platform. A first rotor blade is coupled to a rotor disk. A second rotor blade is coupled to the rotor disk, such that a cavity is defined between the first and second rotor blades, and such that a seal path is defined between a first rotor blade cover plate and a second rotor blade cover plate.

Abstract: A bucket assembly cooling apparatus is provided. The bucket assembly includes a platform, an airfoil, and a shank. The airfoil may extend radially outward from the platform. The shank may extend radially inward from the platform. The shank may include a pressure side sidewall, a suction side sidewall, an upstream sidewall, and a downstream sidewall. The sidewalls may at least partially define a cooling circuit. The cooling circuit may be configured to receive a cooling medium and provide the cooling medium to the airfoil. The upstream sidewall may at least partially define an interior cooling passage and at least partially define an exterior ingestion zone. The cooling passage may be configured to provide a portion of the cooling medium from the cooling circuit to the ingestion zone of an adjacent bucket assembly.

Abstract: In one embodiment, a system includes a fuel nozzle that includes a fuel injector that includes a fuel port and a premixer tube. The premixer tube includes a wall disposed about a central passage, multiple air ports extending through the wall into the central passage, and a catalytic region. The catalytic region includes a catalyst, disposed inside the wall along the central passage, configured to increase a reaction of fuel and air.

Abstract: A fuel nozzle for use with a combustion chamber defined within a gas turbine engine and a method for assembling the same are provided. The fuel nozzle includes a swirler assembly and a burner tube that is coupled to a support flange in a detachable manner such that an inner surface of the burner tube circumscribes an outer surface of the swirler assembly during fuel nozzle operation.

Abstract: A combustor includes at least one combustor liner defining a combustion chamber capable of directing combustion products toward a turbine. At least one combustor sleeve is located outside of the combustion chamber and is capable of reducing a magnitude of acoustic waves in the combustion chamber. The at least one combustor liner and the at least one combustor sleeve define at least one flow channel therebetween. Further, a combustor includes at least one combustor liner defining a combustion chamber capable of directing combustion products toward turbomachinery. At least one combustor sleeve disposed outside of the combustion chamber and is capable of controlling distribution of fluid flow in the combustor to modify a uniformity of the fluid flow to the combustion chamber.

Abstract: A method for cooling a turbine assembly component of a gas turbine engine in a combined-cycle power generation system. The method includes channeling cooling fluid that is extracted from a source external to the gas turbine engine to the turbine assembly component, and cooling the turbine assembly component using the cooling fluid.

Abstract: A method of assembling a combustor assembly is provided, wherein the method includes providing a combustor liner having a centerline axis and defining a combustion chamber therein, and coupling an annular flowsleeve radially outward from the combustor liner such that an annular flow path is defined substantially circumferentially between the flowsleeve and the combustor liner. The method also includes orienting the flowsleeve such that a plurality of inlets formed within the flowsleeve are positioned to inject cooling air in a substantially axial direction into the annular flow path to facilitate cooling the combustor liner.

Abstract: A system for cooling at least one gas turbine liquid fuel component located in a high temperature environment to eliminate coking in the component is disclosed. The system includes a sleeve surrounding the liquid fuel component, a device for providing a current of cool air, and a conduit connected between the cool air device and the sleeve to direct the current of cool air into the sleeve to cool the liquid fuel component. The system can also include a manifold connected to the conduit and a plurality of second conduits for connecting the manifold to a plurality of sleeves surrounding a plurality of liquid fuel components, each sleeve being connected to a corresponding second conduit. Each sleeve includes a plurality of spacing devices for centering the sleeve around the at least one liquid fuel component so as to form an annulus between the sleeve and the liquid fuel component through which the current of cool air flows.

Abstract: A method to ventilate a rotary machine housed in a compartment having a ventilation air inlet and air exhaust, a variable speed ventilation fan and a temperature sensor, wherein the method includes: sensing a temperature level of the rotary machine; applying the sensed machine temperature level to a controller for the fan; drawing ventilation flow through the compartment and over the machine; determining whether the sensed machine temperature level is above a desired temperature level of the rotary machine, wherein the desired temperature level is determined by the controller, and the controller setting an operational condition of the fan to increase the ventilation flow through the compartment if the sensed machine temperature level is above the desired temperature level.