Airfoil for a first stage nozzle guide vane
The present invention provides an airfoil for a first stage nozzle guide vane having an external surface with first and second sides. The external surface extends spanwise between a hub and a tip and streamwise between a leading edge and a trailing edge of the airfoil. The external surface includes a contour substantially defined by Table 1 as listed in the specification.
1. An airfoil comprising:
an external surface having first and second sides, the external surface extending spanwise between a hub and a tip and streamwise between a leading edge and a trailing edge; and
the external surface having a contour substantially defined by Table 1 as listed in the specification.
2. The airfoil of claim 1 , further comprising:
at least one coating formed on the external surface thereof.
3. The airfoil of claim 2 , wherein the external surface including the at least one coating substantially meets the contour dimensions defined by Table 1.
4. The airfoil of claim 2 , wherein an outer surface of the at least one coating extends outside of the contour dimensions as substantially defined by Table 1.
5. The airfoil of claim 2 , wherein the coating includes at least one of a thermal barrier coating and a radiation barrier coating.
6. The airfoil of claim 1 , wherein a portion of the external surface includes at least one discontinuity.
7. The airfoil of claim 6 , wherein the at least one discontinuity includes a through aperture formed in at least one of the sides of the airfoil to provide an outlet path for cooling fluid to flow therethrough.
8. The airfoil of claim 1 , wherein the airfoil is connected to a first stage turbine nozzle guide vane assembly.
9. The airfoil of claim 1 , wherein the positional tolerance of the external surface is held to range of about +/−0.025 inches for each dimension listed in Table 1.
10. A turbine nozzle guide vane assembly for a gas turbine engine comprising:
an inner shroud having an upper surface and a lower surface, the upper surface of the inner shroud partially defining an inner flow path wall;
an airfoil extending radially outward from the upper surface of the inner shroud relative to an axis of rotation of the gas turbine engine, the airfoil having first and second three-dimensional external surfaces extending between a hub and a tip in a spanwise direction and between a leading edge and a trailing edge in a streamwise direction; and
a Cartesian coordinate array having X,Y and Z axis coordinates listed in Table 1 of the specification defining the first and second external surfaces of the airfoil, wherein the Z axis generally extends radially outward from at least one of the upper surface of the inner shroud or a longitudinal axis of the engine, the X axis generally extends normal to the Z axis in the streamwise direction, and the Y axis generally extends normal to both the X axis and the Z axis in a lateral direction.
11. The turbine nozzle guide vane assembly of claim 10 , wherein the external surface of the airfoil is formed within a manufacturing tolerance of about +/−0.025 inches of each dimension listed in Table 1.
12. The turbine nozzle guide vane assembly of claim 10 , wherein the Z axis further defines a stacking axis extending at a predefined angle from the inner shroud.
13. The turbine nozzle guide vane assembly of claim 12 , wherein the angle of the stacking axis is located between a normal position and 25° from the normal position in any direction.
14. The turbine nozzle guide vane assembly of claim 10 , further comprising:
at least one coating formed on the external surface of the airfoil.
15. The turbine nozzle guide vane assembly of claim 14 , wherein the at least one coating is applied to the airfoil such that an outer surface of the coating is located within a tolerance of +/−0.050 inches of the coordinate dimensions defined in Table 1.
16. The turbine nozzle guide vane assembly of claim 14 , wherein the coating is at least one of a thermal barrier coating and a radiation barrier coating.
17. The turbine nozzle guide vane assembly of claim 10 , wherein a portion of the external surface of the airfoil includes at least one discontinuity.
18. The turbine nozzle guide vane assembly of claim 17 , wherein the at least one discontinuity includes a through aperture formed in at least one of the sides of the airfoil to provide an outlet path for cooling fluid to flow therethrough.
19. The turbine nozzle guide vane assembly of claim 10 , wherein the airfoil includes an outer shroud formed adjacent the tip.
20. A method of forming an airfoil for a turbine nozzle guide vane comprising:
forming a contoured three-dimensional external surface of an airfoil defined by Cartesian (X, Y and Z) coordinates listed in the specification as Table 1, wherein the Z axis coordinates are generally measured from an inner shroud or an engine centerline axis, the X axis coordinates are generally measured normal to the Z axis in a streamwise direction, and the Y axis coordinates are generally measured normal to the Z axis and normal to the X axis.
21. The method of claim 20 , further comprising:
forming the airfoil from a casting process, wherein the casting process includes one of integrally casting the turbine nozzle guide vane in one piece and casting multiple pieces and subsequently bonding the cast pieces together.
22. The method of claim 20 , further comprising:
forming the airfoil from a wrought material; and
machine processing a portion of the airfoil to meet a design specification.