Abstract: Embodiments of the invention relate generally to rotary machines and, more particularly, to the control of wheel space purge air in gas turbines. In one embodiment, the invention provides a turbine bucket comprising: a platform portion; an airfoil extending radially outward from the platform portion; a shank portion extending radially inward from the platform portion; an angel wing extending axially from a face of the shank portion; and a plurality of voids disposed along a length of the angel wing, each of the plurality of voids extending radially through the angel wing.

Abstract: Embodiments of the invention relate generally to rotary machines and, more particularly, to the cooling of at least portions of a turbine bucket. In one embodiment, the invention provides a method of cooling at least a portion of a turbine bucket, the method comprising: during operation of a turbine, altering a swirl velocity of purge air beneath a platform lip extending axially from the platform, wherein altering the swirl velocity of the purge air includes interrupting a flow of the purge air with a plurality of voids disposed along a length of an angel wing extending axially from a face of a shank portion of the turbine bucket.

Abstract: Embodiments of the invention relate generally to rotary machines and, more particularly, to the cooling of at least portions of a turbine bucket. In one embodiment, the invention provides a method of cooling at least a portion of a turbine bucket, the method comprising: during operation of a turbine, altering a swirl velocity of purge air beneath a platform lip extending axially from the platform, wherein altering the swirl velocity of the purge air includes interrupting a flow of the purge air with a plurality of voids disposed along a length of an angel wing extending axially from a face of a shank portion of the turbine bucket.

Abstract: Transition duct assemblies for turbine systems and turbomachines are provided. In one embodiment, a transition duct assembly includes a plurality of transition ducts disposed in a generally annular array and comprising a first transition duct and a second transition duct. Each of the plurality of transition ducts includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of each transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct assembly further includes an aerodynamic structure defined by the passages of the first transition duct and the second transition duct. The aerodynamic structure includes a pressure side, a suction side, and a trailing edge, the trailing edge having a modified aerodynamic contour.

Abstract: Embodiments of the invention relate generally to rotary machines and, more particularly, to the control of wheel space purge air in gas turbines. In one embodiment, the invention provides a turbine bucket comprising: a platform portion; an airfoil extending radially outward from the platform portion; a shank portion extending radially inward from the platform portion; an angel wing extending axially from a face of the shank portion; and a plurality of voids disposed along a length of the angel wing, each of the plurality of voids extending radially through the angel wing.

Abstract: Transition duct assemblies for turbine systems and turbomachines are provided. In one embodiment, a transition duct assembly includes a plurality of transition ducts disposed in a generally annular array and comprising a first transition duct and a second transition duct. Each of the plurality of transition ducts includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of each transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct assembly further includes an aerodynamic structure defined by the passages of the first transition duct and the second transition duct. The aerodynamic structure includes a pressure side, a suction side, and a trailing edge, the trailing edge having a modified aerodynamic contour.

Abstract: A turbine bucket includes a radially inner mounting portion, a shank radially outward of the mounting portion, a radially outer airfoil and a substantially planar platform radially between the shank, and the airfoil. At least one axially-extending angel wing seal flange is formed on a leading end of the shank forming a circumferentially extending trench cavity along the leading edge of the shank, radially between an underside of the platform leading edge and the angel wing seal flange. A plurality of substantially radially-extending purge air holes are formed in the angel wing seal flange, adapted to fluidly connect a turbine rotor wheel space cavity with the trench cavity and thereby supply purge air to the outer surface of the angel wing seal flange.

Abstract: A turbine bucket includes a radially inner mounting portion; a shank radially outward of the mounting portion; at least one radially outer airfoil having a leading edge and a trailing edge; a substantially planar platform radially between the shank and the at least one radially outer airfoil; at least one axially-extending angel wing seal flange on a leading end of the shank thus forming a circumferentially extending trench cavity along the leading end of the shank, radially between an underside of the platform leading edge and a radially outer side of the angel wing seal flange; and slash faces along opposite, circumferentially-spaced side edges of the platform. At least one of the slash faces is formed with a dog-leg shape, a leading end of the at least one of slash face terminating at a location circumferentially offset from the leading edge of the at least one radially outer airfoil.

Abstract: A turbine bucket includes a radially inner mounting portion, a shank radially outward of the mounting portion, a radially outer airfoil and a substantially planar platform radially between the shank and the airfoil. At least one axially-extending angel wing seal flange is formed on a leading end of the shank thus forming a circumferentially extending trench cavity along the leading end of the shank, radially between an underside of the platform leading edge and the angel wing seal flange. A plurality of substantially radially grooves are formed on a radially outer surface of the angel wing seal flange and extend into the shank.

Abstract: A turbine bucket includes a platform and an airfoil. A leading edge of the platform leading is circumferentially defined by a continuous curve forming at least one axially extending projection and an adjacent recess, the axially-extending projection located adjacent a leading edge of the airfoil.

Abstract: A turbine bucket includes a radially inner mounting portion, a shank radially outward of the mounting portion, a radially outer airfoil and a substantially planar platform radially between the shank, and the airfoil. At least one axially-extending angel wing seal flange is formed on a leading end of the shank forming a circumferentially extending trench cavity along the leading edge of the shank, radially between an underside of the platform leading edge and the angel wing seal flange. A plurality of substantially radially-extending purge air holes are formed in the angel wing seal flange, adapted to fluidly connect a turbine rotor wheel space cavity with the trench cavity and thereby supply purge air to the outer surface of the angel wing seal flange.

Abstract: A turbine bucket includes a radially inner mounting portion; a shank radially outward of the mounting portion; at least one radially outer airfoil having a leading edge and a trailing edge; a substantially planar platform radially between the shank and the at least one radially outer airfoil; at least one axially-extending angel wing seal flange on a leading end of the shank thus forming a circumferentially extending trench cavity along the leading end of the shank, radially between an underside of the platform leading edge and a radially outer side of the angel wing seal flange; and slash faces along opposite, circumferentially-spaced side edges of the platform. At least one of the slash faces is formed with a dog-leg shape, a leading end of the at least one of slash face terminating at a location circumferentially offset from the leading edge of the at least one radially outer airfoil.

Abstract: A turbine bucket includes a platform and an airfoil. A leading edge of the platform leading is circumferentially defined by a continuous curve forming at least one axially extending projection and an adjacent recess, the axially-extending projection located adjacent a leading edge of the airfoil.

Abstract: A turbine bucket includes a radially inner mounting portion, a shank radially outward of the mounting portion, a radially outer airfoil and a substantially planar platform radially between the shank and the airfoil. At least one axially-extending angel wing seal flange is formed on a leading end of the shank thus forming a circumferentially extending trench cavity along the leading end of the shank, radially between an underside of the platform leading edge and the angel wing seal flange. A plurality of substantially radially grooves are formed on a radially outer surface of the angel wing seal flange and extend into the shank.

Abstract: A turbomachine component includes a main body having a gas path surface configured to be exposed to gases passing along a turbomachine gas path, a non gas path surface configured to be arranged in a turbomachine wheelspace outside the turbomachine gas path, and a non-axisymetric flow contour feature extending from the gas path surface to the non gas path surface.