Patent ID: 7303372

Claim:
A turbine nozzle cooling sub-system, said sub-system comprising: at least one turbine nozzle segment comprising an arcuate, radially outermost endwall, an arcuate, radially innermost endwall, and at least one airfoil vane, wherein said outermost endwall comprises at least one open passage, said innermost endwall comprises at least one open passage, said at least one airfoil vane extends between and is coupled to said inner radial endwall and said outer radial endwall, said vane further comprises a cavity, a leading edge, a trailing edge, and an airfoil vane external surface, said cavity comprises an airfoil vane internal surface and a plurality of turbulators, said cavity and said open passages being in flow communication such that an airfoil cooling air stream flow is facilitated; and at least one diffuser in flow communication with a compressor assembly and said at least one turbine nozzle segment, said diffuser comprises at least one diffuser wall and at least one cavity, said at least one diffuser wall extends from the compressor assembly to said turbine nozzle segment such that a channeling of said airfoil cooling air stream to said at least one turbine nozzle segment is facilitated, said airfoil cooling air stream comprises at least a portion of a compressor assembly discharge air stream flow.