Abstract: A turbine blade includes a shank portion and an airfoil portion with leading and trailing edges and a radially outer tip. An internal closed-loop cooling circuit is formed within the airfoil portion and includes at least one radial outflow passage and at least one radial inflow passage connected by at least one respective tip turn at the radially outer end of the airfoil portion. At least one tip turn is provided with a single turbulence-enhancement device on an underside of the radially outer tip, projecting into the tip turn.

Abstract: A turbine blade includes a shank portion and an airfoil portion with leading and trailing edges and a radially outer tip. An internal closed-loop cooling circuit is formed within the airfoil portion and includes at least one radial outflow passage and at least one radial inflow passage connected by at least one respective tip turn at the radially outer end of the airfoil portion. At least one tip turn is provided with a single turbulence-enhancement device on an underside of the radially outer tip, projecting into the tip turn.

Abstract: A double wall bearing cone closes an opening between a bearing housing and an exhaust frame in a gas turbine. The bearing cone includes a conical forward plate having an inner diameter and an outer diameter and a conical aft plate nested with and spaced from the conical forward plate. A hub connects the inner diameters of the forward plate and the aft plate. The hub preferably includes holes therein that serve to meter air flow between the forward plate and the aft plate. The double wall bearing cone defines a cooling circuit that reduces wear between a third stage turbine wheel in a gas turbine and the rotor aft shaft.