Airfoils

1. An airfoil cluster comprising:

an inner diameter platform;

an outer diameter platform; and

a plurality of airfoils extending radially from the inner diameter platform to the outer diameter platform, each airfoil including a leading edge and a trailing edge with an exterior surface therebetween, wherein the exterior surface includes a pressure side, a suction side and a recessed portion on the pressure side adjacent to the trailing edge, wherein the trailing edge is an arcuate surface connecting between the suction side and the pressure side, the pressure side further including a flat non-recessed surface and a flat recessed surface with a continuously curved transition surface therebetween, the flat non-recessed surface and the flat recessed surface being proximate to the trailing edge, the flat recessed surface being part of the recessed portion; and the flat recessed surface is tangent to the arcuate surface of the trailing edge and is at an angle with respect to the flat non-recessed surface, wherein the exterior surface of at least one of the airfoils is formed in substantial conformance with a set of Cartesian coordinates set forth in one of Table 1, Table 2 or Table 3, wherein the Cartesian coordinates are provided by an axial coordinate scaled by a local chord length, a circumferential coordinate scaled by the local chord length, and a span location, wherein the local chord length corresponds to a respective width of each airfoil between the leading and trailing edges at 50% span.

2. The airfoil cluster as recited in claim 1 , wherein the plurality of airfoils includes three hollow vanes.

3. The airfoil cluster as recited in claim 1 , wherein the plurality of airfoils ranges from two to six hollow vanes.

4. A method for adjusting flow area between airfoils in a cluster:

manufacturing an airfoil cluster including:

an inner diameter platform;

an outer diameter platform; and

a plurality of airfoils extending radially from the inner diameter platform to the outer diameter platform, each airfoil having a leading edge and a trailing edge, and pressure and suction sides between the leading and trailing edges, wherein manufacturing the airfoil cluster includes generating a recessed portion on the pressure side adjacent to the trailing edge, wherein the trailing edge is an arcuate surface connecting between the suction side and the pressure side, the pressure side further including a flat non-recessed surface and a flat recessed surface with a continuously curved transition surface therebetween, the flat non-recessed surface and the flat recessed surface are proximate to the trailing edge, the flat recessed surface being part of the recessed portion and generating an exterior surface of at least one of the airfoils in substantial conformance with a set of Cartesian coordinates set forth in at least one of Table 1, Table 2 or Table 3, wherein the Cartesian coordinates are provided by an axial coordinate scaled by a local chord length, a circumferential coordinate scaled by the local chord length, and a span location, wherein the local chord length corresponds to a respective width of each airfoil between the leading and trailing edges at 50% span; and wherein the flat recessed surface is tangent to the arcuate surface of the trailing edge and is at an angle with respect to the flat non-recessed surface.

5. The method as recited in claim 4 , wherein generating the recessed portion includes at least one of casting or machining.

6. An airfoil comprising:

an airfoil body including:

a leading edge and a trailing edge with an exterior surface therebetween, wherein the exterior surface includes a pressure side, a suction side, and a recessed portion on the pressure side adjacent to the trailing edge, the trailing edge being an arcuate surface connecting between the suction side and the pressure side, and the pressure side further includes a flat non-recessed surface and a flat recessed surface with a continuously curved transition surface therebetween, the flat non-recessed surface and the flat recessed surface are proximate to the trailing edge, and the flat recessed surface being part of the recessed portion, and the flat recessed surface is tangent to the arcuate surface of the trailing edge and is at an angle with respect to the flat non-recessed surface; and wherein the exterior surface is formed in substantial conformance with a set of Cartesian coordinates set forth in at least one of Table 1, Table 2 or Table 3, wherein the Cartesian coordinates are provided by an axial coordinate scaled by a local chord length, a circumferential coordinate scaled by the local chord length, and a span location, wherein the local chord length corresponds to a respective width of each airfoil between the leading and trailing edges at 50% span.

7. The airfoil as recited in claim 6 , wherein the airfoil body is a hollow vane.

8. An airfoil comprising:

an airfoil body having a leading edge and a trailing edge with an exterior surface therebetween, wherein the exterior surface includes a recessed portion on a pressure side of the airfoil adjacent to the trailing edge, wherein the exterior surface is formed in substantial conformance with a set of Cartesian coordinates set forth in at least one of Table 1, Table 2 or Table 3, wherein the Cartesian coordinates are provided by an axial coordinate scaled by a local chord length, a circumferential coordinate scaled by the local chord length, and a span location, wherein the local chord length corresponds to a respective width of each airfoil between the leading and trailing edges at 50% span.

9. The airfoil as recited in claim 8 , wherein substantial conformance with the set of Cartesian coordinates set forth in Tables 1, 2 and 3 includes values within ±15% of each coordinate.

10. The airfoil as recited in claim 8 , wherein a manufacturing tolerance relative to the set of Cartesian coordinates is ±3.6% of the local chord length of the airfoil body.