Airfoil with tip rail cooling

1. An airfoil for a turbine engine, the airfoil comprising:

a body defining an interior, and extending axially between a leading edge and a trailing edge to define a chord-wise direction and radially between a root and a tip to define a span-wise direction, which terminates in a tip wall and a tip rail extending from the tip wall;

at least one cooling passage formed in the interior;

at least one cooling cavity provided within the tip rail and comprising at least one cooling conduit defining a flow path having a centerline intersecting with a first surface of the cooling cavity and fluidly coupled to the cooling passage; and

at least one film-hole extending in a separate plane from, and non-aligned in the chord-wise direction with, the at least one cooling conduit having an inlet fluidly coupled to the at least one cooling cavity at a second surface opposite the first surface and an outlet provided on an exterior surface of the tip rail.

2. The airfoil of claim 1 wherein the at least one cooling cavity comprises multiple cooling cavities.

3. The airfoil of claim 2 wherein the at least one cooling conduit comprises multiple cooling conduits.

4. The airfoil of claim 1 wherein the at least one cooling conduit comprises a curved cooling conduit.

5. The airfoil of claim 4 wherein the at least one cooling conduit comprises multiple cooling conduits.

6. The airfoil of claim 1 wherein the at least one cooling conduit comprises multiple cooling conduits.

7. The airfoil of claim 1 further comprising a plurality of film-holes provided along a distal end of the tip rail.

8. The airfoil of claim 1 wherein the exterior surface comprises an outer wall and the outlet is fluidly coupled to a source of air at the outer wall.

9. The airfoil of claim 1 wherein the exterior surface defines a tip plenum and the outlet is fluidly coupled to the tip plenum.

10. The airfoil of claim 1 wherein the cooling cavity extends along a length of the tip rail.

11. The airfoil of claim 1 wherein the cooling cavity comprises axially-spaced cooling cavities.

12. The airfoil of claim 1 wherein the at least one film-hole is multiple film-holes comprising a first and second set of film holes.

13. The airfoil of claim 12 wherein the multiple film-holes includes a third set of film-holes.

14. A blade for a turbine engine, the blade comprising:

a body defining an interior, and extending axially between a leading edge and a trailing edge to define a chord-wise direction and radially between a root and a tip to define a span-wise direction, which terminates in a tip wall and a tip rail extending from the tip wall;

at least one cooling passage formed in the interior;

at least one cooling cavity provided within the tip rail and comprising at least one cooling conduit defining a flow path having a centerline intersecting with a first surface defining a hole-free region of the cooling cavity and fluidly coupled to the cooling passage; and

at least one film-hole with the at least one cooling conduit having an inlet fluidly coupled to the at least one cooling cavity at a second surface opposite the first surface and an outlet provided on an exterior surface of the tip rail.

15. The blade of claim 14 wherein the at least one cooling cavity comprises multiple cooling cavities.

16. The blade of claim 15 wherein the at least one cooling conduit comprises multiple cooling conduits.

17. The blade of claim 14 wherein the at least one cooling conduit comprises a curved cooling conduit.

18. The blade of claim 17 wherein the at least one cooling conduit comprises multiple cooling conduits.

19. The blade of claim 14 wherein the at least one cooling conduit comprises multiple cooling conduits.

20. The blade of claim 14 further comprising a plurality of film-holes provided along a distal end of the tip rail.

21. The blade of claim 14 wherein the exterior surface comprises an outer wall and the outlet is fluidly coupled to a source of air at the outer wall.

22. The blade of claim 14 wherein the exterior surface defines a tip plenum and the outlet is fluidly coupled to the tip plenum.

23. The blade of claim 14 wherein the cooling cavity extends along a length of the tip rail.

24. The blade of claim 14 wherein the cooling cavity comprises axially-spaced cooling cavities.

25. The blade of claim 14 wherein the at least one film-hole is multiple film-holes comprising a first and second set of film holes.

26. The blade of claim 25 wherein the multiple film-holes includes a third set of film-holes.

27. A method of cooling a tip rail of an airfoil for a turbine engine, the method comprising:

impinging a cooling fluid through a flow path onto a first surface defining a hole-free region of a cooling cavity within the tip rail; and

exhausting at least a portion of cooling fluid through at least one film-hole having an inlet provided on a second surface of the cooling cavity opposite the first surface and extending to an outlet in the tip rail.

28. The method of claim 27 wherein the impinging a cooling fluid further includes impinging the cooling fluid through a curved cooling conduit.

29. The method of claim 27 wherein the exhausting at least a portion of cooling fluid includes exhausting a remaining portion of cooling fluid through a plurality of film-holes.

30. The method of claim 29 further including impinging the remaining portion of cooling fluid onto a shroud segment.

31. The method of claim 27 wherein the exhausting at least a portion of cooling fluid includes exhausting the cooling fluid through at least one film-hole located along an outer wall of the airfoil.

32. The method of claim 27 wherein the exhausting at least a portion of cooling fluid includes exhausting the cooling fluid through a second set of film-holes located along a surface differing from the at least one film-hole.