Patent attributes
A film cooling hole for a turbine airfoil. the first embodiment is a film cooling hole aligned with the stream-wise direction of the hot gas flow over the hole and includes a metering section followed by a diffuser section. The diffuser section includes a left side wall and a right side wall both having a curvature facing outward and at about the same radius of curvature. The diffuser section also includes a top side wall and a bottom side wall which both have a curvature in the stream-wise direction, and in which the radius of curvature of the top side wall is greater than the radius of curvature of the bottom side wall. A second embodiment is a film cooling hole offset from the stream-wise direction of flow and includes the four walls with a curvature, but in which the left side wall has a greater radius of curvature than the right side wall due to the stream-wise offset of the hole.
