Patent ID: 6884036

Claim:
A second stage gas turbine nozzle comprising: outer and inner bands integrally joined to a vane therebetween; said vane including opposite pressure and suction sidewalls joined together at opposite leading and trailing edges; said sidewalls being spaced apart to define a three-pass serpentine flow circuit including a first channel extending behind said leading edge, a second channel separated in part from said first channel by an imperforate forward bridge extending from said outer band short of said inner band, and a third channel spaced in part from said second channel by an imperforate aft bridge extending from said inner band short of said outer band; said outer band including an inlet at said first channel for feeding pressurized cooling air thereto, said inner band including a first outlet at said first channel for discharging a portion of said air, and a second outlet at said third channel for discharging another portion of said air, and said vane including a row of outlet holes along said trailing edge in flow communication with said third channel for discharging remaining air therefrom; and said first channel being smooth except for a first row of first turbulators bridging said pressure and suction sidewalls directly behind said leading edge opposite said forward bridge, and a second row of second turbulators spaced laterally from said first row behind said suction sidewall, with said pressure sidewall being otherwise devoid of turbulators opposite said forward bridge.