Airfoil shape for a turbine bucket

1. A turbine bucket including a bucket airfoil having an airfoil shape, said airfoil having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 0.938 convertible to Z distances in inches by multiplying the Z values by a height of the airfoil in inches, and wherein X and Y are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape.

2. A turbine bucket according to claim 1 forming part of a third stage of a turbine.

3. A turbine bucket according to claim 1 wherein said airfoil shape lies in an envelope within ±0.150 inches in a direction normal to any airfoil surface location.

4. A turbine bucket according to claim 1 wherein the height of the airfoil from a value of Z=0 to a value of Z=0.938 is 15.146 inches.

5. A turbine bucket including a bucket airfoil having an uncoated nominal airfoil profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 0.938 convertible to Z distances in inches by multiplying the Z values by a height of the airfoil in inches, and wherein X and Y are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each Z distance, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape, the X and Y values being scalable as a function of the same constant or number to provide a scaled-up or scaled-down airfoil.

6. A turbine bucket according to claim 5 forming part of a third stage of a turbine.

7. A turbine bucket according to claim 5 wherein said airfoil shape lies in an envelope within ±0.150 inches in a direction normal to any airfoil surface location.

8. A turbine bucket according to claim 5 wherein the height of the airfoil from a value of Z=0 to a value of Z=0.938 is 15.146 inches.

9. A turbine comprising a turbine wheel having a plurality of buckets, each of said buckets including an airfoil having an airfoil shape, said airfoil having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 0.938 convertible to Z distances in inches by multiplying the Z values by a height of the airfoil in inches, and wherein X and Y are distances in inches which, when connected by smooth continuing arcs, define the airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape.

10. A turbine according to claim 9 wherein the turbine wheel comprises a third stage of the turbine.

11. A turbine according to claim 9 wherein the turbine wheel has 92 buckets and X represents a distance parallel to the turbine axis of rotation.

12. A turbine according to claim 9 wherein the height of the airfoil from a value of Z=0 to a value of Z=0.938 is 15.146 inches.

13. A turbine according to claim 9 wherein the radial height between an axial centerline of said turbine wheel and a hub radius of each bucket airfoil at a leading edge thereof is 40.716 inches, the non-dimensionalized Z value at Z=0.000 starting at a radial height 41.891 inches from the axial centerline of the turbine wheel.

14. A turbine according to claim 13 wherein the height of the airfoil from a value of Z=0 to a value of Z=0.938 is 15.146 inches.

15. A turbine comprising a turbine wheel having a plurality of buckets, each of said buckets including an airfoil having an uncoated nominal airfoil profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein the Z values are non-dimensional values from 0 to 0.938 convertible to Z distances in inches by multiplying the Z values by a height of the airfoil in inches, and wherein X and Y are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z, the profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape, the X and Y distances being scalable as a function of the same constant or number to provide a scaled-up or scaled-down bucket airfoil.

16. A turbine according to claim 15 wherein the turbine wheel comprises a third stage of the turbine.

17. A turbine according to claim 15 wherein the turbine wheel has 92 buckets and X represents a distance parallel to the turbine axis of rotation.

18. A turbine according to claim 15 wherein the height of the airfoil from a value of Z=0 to a value of Z=0.938 is 15.146 inches.

19. A turbine according to claim 15 wherein the radial height between an axial centerline of said turbine wheel and a hub radius of each bucket at a leading edge thereof is 40.716 inches, the non-dimensionalized Z value at 0.000 starting at a radial height 41.891 inches from the axial centerline of the turbine wheel.

20. A turbine according to claim 19 wherein the height of the airfoil from a value of Z=0 to a value of Z=0.938 is 15.146 inches.

21. A turbine according to claim 15 wherein the Z=0 coordinate value corresponds to 1.175 inches radially outwardly of an inlet hub radius of 40.716 inches at the leading edge of the airfoil.