Abstract: Method and apparatus are disclosed for providing a closed-loop air cooling system for a turbine engine. The method and apparatus provide for bleeding pressurized air from a gas turbine engine compressor for use in cooling the turbine components. The compressed air is cascaded through the various stages of the turbine. At each stage a portion of the compressed air is returned to the compressor where useful work is recovered.

Abstract: A gas turbine that has turbine vanes that can be cooled with either steam or air includes a compressor that compresses air, a combustor enclosed within a shell and in flow communication with the compressor, a turbine in flow communication with the combustor and receiving hot gas from the combustor and turbine vanes. The turbine vanes having an airfoil, a shroud and a cooling circuit that cools the airfoil and the shrouds with either steam or air.

Abstract: An apparatus for cooling the trailing edge portion of a gas turbine vane. Two radially extending passages connected to the outer shroud direct cooling fluid to a plenum formed about mid-span adjacent the trailing edge. Two arrays of cooling fluid passages extend from the plenum. One array extends radially outward toward the outer shroud while the other array extends radially inward toward the inner shroud. The plenum distributes the cooling fluid to the two arrays of passages so that it flows radially inward and outward to manifolds formed in the inner and outer shrouds. The manifolds direct the spent cooling fluid to a discharge passage.