Patent ID: 8231329

Claim:
A turbine blade with a generally hollow airfoil having an outer wall that defines a chamber for receiving cooling air, the airfoil comprising a leading edge that resides in an upstream direction, a trailing edge that resides in a downstream direction, a convex suction side, a concave pressure side, and an insert disposed within the chamber that is configured to initially receive at least a portion of the cooling air entering the chamber and direct the cooling air through a plurality of insert apertures to cool the inner surface of the outer wall, the insert further comprising a configuration that generally conforms to the contour of the outer wall of the chamber but in spaced relation thereto, wherein a portion of the cooling air exits the airfoil through a plurality of film cooling apertures formed through the outer wall, wherein the chamber and insert narrow as they extend toward the trailing edge, the insert eventually terminating and the chamber eventually terminating at a pin array section, which includes a passageway in which a plurality of cooling pins extend transversely across and are integral to the opposed walls that define the pin array section, wherein a first distance exists that comprises the generally axial distance between the position of downstream termination point of the insert and the position of an upstream beginning point of the pin array section, wherein the pin array section, at a downstream end, comprises a plurality of openings that define an inlet to a plurality of trailing edge cooling apertures that extend from the pin array section to the trailing edge of the airfoil where an outlet is provided through which a portion of the cooling air may exit the airfoil, and wherein the chamber, the insert, and the pin array section are configured such that the first distance is approximately minimized; wherein the configuration of the chamber, the insert, and the pin array section that approximately minimizes the first distance includes a contoured exit that makes a smooth transition from the broader diameter of the chamber to the narrow diameter of the pin array section.