Abstract: A turbine shroud for turbine systems may include a forward end including a first hook coupled to the turbine casing, an aft end including a second hook coupled to the turbine casing, and a base portion extending between the forward end and the aft end. The base portion may include an inner surface facing a hot gas flow path for the turbine system. Also, the turbine shroud may include a flange extending from the aft end and positioned radially between the base portion and the second hook, a cooling passage positioned within the base portion, adjacent the inner surface, and at least one aft end exhaust conduit in fluid communication with the cooling passage. The aft end exhaust conduit(s) may extend through the aft end, radially between the base portion and the flange.

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 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.

Abstract: 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.

Abstract: A turbine casing includes at least one shell adapted to enclose one or more turbine stages in a gas turbine engine; an air inlet in the at least one shell; a flow sleeve secured to an inside surface of the at least one shell, the flow sleeve comprising at least two arcuate segments. Each arcuate segment includes an arcuate base, a pair of sidewalls extending radially outwardly of the base thereby forming a circumferentially-extending flow channel defined by the base, the sidewalls and the inside surface. The air inlet is aligned with the flow channel and the sleeve is configured to distribute air flowing in the channel into spaces proximate the one or more turbine stages in circumferential, radial and axial directions, including along the inside surface of the at least one shell.

Abstract: A system is provided including a turbine exhaust section. The turbine exhaust section includes an exhaust flow path. The turbine exhaust section also includes an outer structure having an outer casing, an outer exhaust wall disposed along the exhaust flow path, and an outer cavity disposed between the outer exhaust wall and the outer casing. The turbine exhaust section further includes an inner structure having an inner exhaust wall disposed along the exhaust flow path, an inner cavity disposed between the inner exhaust wall and an inner casing, and a bearing cavity disposed between the inner casing and a bearing housing. In addition, the turbine exhaust section includes a strut extending between the outer structure and the inner structure. The strut includes a first flow passage configured to flow a fluid from the inner cavity to the outer cavity.

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 turbine casing includes at least one shell adapted to enclose one or more turbine stages in a gas turbine engine; an air inlet in the at least one shell; a flow sleeve secured to an inside surface of the at least one shell, the flow sleeve comprising at least two arcuate segments. Each arcuate segment includes an arcuate base, a pair of sidewalls extending radially outwardly of the base thereby forming a circumferentially-extending flow channel defined by the base, the sidewalls and the inside surface. The air inlet is aligned with the flow channel and the sleeve is configured to distribute air flowing in the channel into spaces proximate the one or more turbine stages in circumferential, radial and axial directions, including along the inside surface of the at least one shell.

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 clearance control system for a rotary machine includes an outer casing including an outer casing main portion having a first radial thickness, wherein the outer casing is configured to expand at a first time rate of thermal expansion. Also included is an inner casing disposed between the outer casing and a rotary portion, the inner casing including an inner casing main portion having a second radial thickness that is less than the first radial thickness, wherein the inner casing is configured to expand at a second time rate of thermal expansion that is greater than the first time rate of thermal expansion of the outer casing. Further included is an inner casing leg configured to separate from an outer casing leg during expansion of the inner casing and configured to engage the outer casing leg during contraction of the inner casing.

Abstract: A turbine casing includes at least one shell adapted to enclose one or more turbine stages in a gas turbine engine; an air inlet in the at least one shell; a flow sleeve secured to an inside surface of the at least one shell, the flow sleeve comprising at least two arcuate segments. Each arcuate segment includes an arcuate base, a pair of sidewalls extending radially outwardly of the base thereby forming a circumferentially-extending flow channel defined by the base, the sidewalls and the inside surface. The air inlet is aligned with the flow channel and the sleeve is configured to distribute air flowing in the channel into spaces proximate the one or more turbine stages in circumferential, radial and axial directions, including along the inside surface of the at least one shell.

Abstract: According to one embodiment, there is disclosed an inducer assembly for use with a gas turbine engine. The inducer assembly may include a cavity. The inducer assembly may also include an inducer in fluid communication with the cavity. Moreover, the inducer assembly may include at least one guide vane disposed within the cavity.

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: 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: 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: 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 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 clearance control system for a rotary machine includes an outer casing including an outer casing main portion having a first radial thickness, wherein the outer casing is configured to expand at a first time rate of thermal expansion. Also included is an inner casing disposed between the outer casing and a rotary portion, the inner casing including an inner casing main portion having a second radial thickness that is less than the first radial thickness, wherein the inner casing is configured to expand at a second time rate of thermal expansion that is greater than the first time rate of thermal expansion of the outer casing. Further included is an inner casing leg configured to separate from an outer casing leg during expansion of the inner casing and configured to engage the outer casing leg during contraction of the inner casing.