Patent attributes
An airfoil used in a gas turbine engine, especially a large rotor blade in an industrial gas turbine engine, the airfoil having at least one cooling air supply cavity formed by an inner wall of the airfoil to supply cooling air to the airfoil, and a plurality of mini-serpentine cooling modules formed between the inner wall and the outer wall surface of the airfoil providing near-wall cooling for the airfoil. The modules includes three-pass or five-pass serpentine cooling channels with an inlet in fluid communication with the cooling air supply cavity and an outlet opening onto the airfoil surface to provide film cooling to the airfoil. The length of a straight section of the passage is about 5 to 10 mm and about 1 mm in diameter. A plurality of supply cavities are formed within the inner wall and separated by ribs. A plurality of mini-serpentine cooling modules is arranged along a chordwise length of the airfoil and each is in fluid communication with the nearest supply cavity.
