Airfoil with cast features and method of manufacture

Abstract

An apparatus and method for forming a film hole in an outer wall of an airfoil. The film hole includes a blind opening adjacent the interior of the airfoil and a hole adjacent the exterior of the airfoil. The blind opening fluidly couples to the hole to form the film hole for providing a volume of fluid as a surface cooling film along the exterior of the outer wall.

What is claimed is: 
     
         1 . An airfoil for a turbine engine comprising:
 an outer wall having an outer surface and an inner surface bounding a hollow interior, the outer wall defining a pressure side and a suction side extending axially between a leading edge and a trailing edge and extending radially between a root and a tip;   a plurality of blind openings cast in the inner surface and terminating within the outer wall; and   a plurality of machined openings extending through the outer surface and each machined opening in the plurality of machined openings intersecting a corresponding blind opening in the plurality of blind openings.   
     
     
         2 . The airfoil of  claim 1  wherein the plurality of machined openings forms an angle with the outer surface between 5 degrees and 40 degrees. 
     
     
         3 . The airfoil of  claim 1  wherein the plurality of machined openings forms an angle with the outer surface between 70 degrees and 110 degrees. 
     
     
         4 . The airfoil of  claim 3  wherein the angle is 90 degrees. 
     
     
         5 . The airfoil of  claim 1  wherein at least some of the plurality of blind openings are arranged in rows or columns. 
     
     
         6 . The airfoil of  claim 1  wherein at least some of the plurality of blind openings are arranged in different densities. 
     
     
         7 . The airfoil of  claim 1  wherein the at least one blind opening terminates in a sloped surface to form a fluid deflector in the blind opening. 
     
     
         8 . The airfoil of  claim 7  wherein the plurality of machined openings forms the blind opening opposite the fluid deflector. 
     
     
         9 . The airfoil of  claim 7  wherein the fluid deflector can extend beyond the at least one blind opening to define a joint cavity. 
     
     
         10 . The airfoil of  claim 10  wherein the joint cavity has a semi-circular shape. 
     
     
         11 . The airfoil of  claim 1  wherein the at least one machined opening comprises a slot. 
     
     
         12 . An airfoil for a turbine engine comprising:
 an outer wall having an outer surface and an inner surface bounding an interior, the outer wall defining a pressure side and a suction side extending axially between a leading edge and a trailing edge and extending radially between a root and a tip;   at least one first blind opening formed in the inner surface and terminating within the outer wall; and   at least one second blind opening extending through the outer surface and intersecting the at least one first blind opening.   
     
     
         13 . The airfoil of  claim 12  wherein the at least one second blind opening forms an angle with the outer surface between 5 degrees and 40 degrees. 
     
     
         14 . The airfoil of  claim 12  wherein the at least one second blind opening forms an angle with the outer surface between 70 degrees and 110 degrees. 
     
     
         15 . The airfoil of  claim 12  wherein the at least one first blind opening comprises a plurality of first blind openings. 
     
     
         16 . The airfoil of  claim 15  wherein the at least one second blind opening comprises a plurality of second blind openings. 
     
     
         17 . The airfoil of  claim 16  wherein each second blind opening in the plurality of second blind openings intersect a corresponding first blind opening in the plurality of first blind openings. 
     
     
         18 . The airfoil of  claim 15  wherein the plurality of first blind openings are arranged in rows or columns. 
     
     
         19 . The airfoil of  claim 12  wherein the second blind opening can include a fluid deflector extending beyond the first blind opening to define a joint cavity. 
     
     
         20 . The airfoil of  claim 19  wherein the joint cavity has a semi-circular shape.