This invention is directed generally to turbine airfoils, and more particularly to support systems for hollow turbine airfoils having cooling channels for passing fluids, such as air, to cool the airfoils.
Typically, gas turbine engines include a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, and a turbine blade assembly for producing power. Combustors often operate at high temperatures that may exceed 2,500 degrees Fahrenheit. Typical turbine combustor configurations expose turbine vane and blade assemblies to these high temperatures. As a result, turbine vanes and blades must be made of materials capable of withstanding such high temperatures. In addition, turbine vanes and blades often contain cooling systems for prolonging the life of the vanes and blades and reducing the likelihood of failure as a result of excessive temperatures. Turbine engines typically include a plurality of rows of stationary turbine vanes extending radially inward from a shell and include plurality of rows of rotatable turbine blades attached to a rotor assembly for turning the rotor.
Row one turbine vanes may be axially supported at the ID end of the vanes. Such support schemes for row one turbine vanes should provide fail-safe support structures operable under extreme structural and thermal loading. Conventional support schemes include supporting the row one turbine vane at an OD shroud aft rail and at an ID shroud aft rail from the shaft cover positioned radially inward of the turbine vane. However, such an arrangement can lead to significant leakage at the aft rail because the tangential aero load on the vane can unseat the sealing surfaces at the airfoil concave side end of the aft rails, as shown in
This invention relates to a turbine vane ID support system usable to support an ID of a row one turbine vane. The turbine vane ID support system may be formed from a turbine vane ID support body with a base configured to be attached to a shaft cover or other support structure. The turbine vane ID support system may include a transition seal system extending from the turbine vane ID support body to seal the turbine vane ID support body to a transition. The turbine vane ID support system may also include a turbine vane ID forward rail seal system extending from the turbine vane ID support body to seal the turbine vane ID support body to an ID forward rail of the turbine vane. Thus, a transition seal seals a transition to the turbine vane ID support body, and a forward rail seal seals the turbine vane ID support body to a forward turbine vane rail, thereby reducing or eliminating the problems inherent with conventional seals used to seal transitions directly to turbine vanes.
The turbine vane ID support system may include a turbine vane ID support body with a base configured to be attached to a shaft cover. The turbine vane ID support body may be formed from a plurality of struts forming one or more cooling fluid flow channels through the turbine vane ID support body. A transition seal system may extend from the turbine vane ID support body to seal the turbine vane ID support body to a transition. A turbine vane ID forward rail seal system may extend from the turbine vane ID support body to seal the turbine vane ID support body to a turbine vane ID forward rail of a turbine vane. The transition seal system may be formed from a transition seal support cavity configured to support a transition seal extending between the turbine vane ID support body and a transition. The transition seal may extend from the turbine vane ID support body. The transition seal may be bent such that a portion of the transition seal that contacts the transition is generally orthogonal to a portion of the transition seal housed in the transition seal support cavity. The turbine vane ID forward rail seal system may include a forward rail seal support cavity configured to support a forward rail seal extending between the turbine vane ID support body and a turbine vane.
The turbine vane ID support system may also include a forward rail support arm extending from the turbine vane ID support body. In one embodiment, the transition seal system and the turbine vane ID forward rail seal system may be coupled to the forward rail support arm. The forward rail support arm may include one or more forward rail receiving slots configured to slideably receive a forward turbine vane rail.
The turbine vane ID support system may also include an aft rail support arm extending from the turbine vane ID support body aft of the forward rail support arm. The turbine vane ID support system may include a turbine vane ID aft rail seal system extending from the aft rail support arm to seal an aft turbine vane rail to the turbine vane ID support body. The turbine vane ID aft rail seal system may be formed from one or more aft rail seal cavities in the aft rail support arm, wherein the aft rail seal cavity may house one or more aft rail seals.
An advantage of this invention is that the turbine vane ID support system reduces turbine vane axial sawtoothing at the shroud leading edge enhancing the effectiveness of the turbine vane ID forward rail sealing system.
Another advantage of this invention is that the turbine vane ID support system improves sealing between a turbine vane and a transition by separating transition seals from the turbine vane seals, which eliminates the need for a single seal to accommodate the radial and axial motion of both the transition and the turbine vane. This results in reduced wear, increased engine performance, and reduced life cycle costs.
Yet another advantage of this invention is that the turbine vane ID support system may be used to reduce the tendency of particles in the combustor shell air to contaminate the row one turbine vane cooling air supply in an air cooled vane design.
Another advantage of this invention is that the turbine vane ID support body is formed in segments that, when combined with multiple segments, forms annular ring. One or more of the segments may be removed to allow inspection and removal of the turbine vanes and adjacent blades without removing the turbine engine cover, thereby resulting in substantial time and cost savings.
Still another advantage of this invention is that if access to the turbine vane is not needed for the full circumference, a portion of the turbine vane ID support body can be integral with the shaft cover to reduce cost and leakage.
These and other embodiments are described in more detail below.
The accompanying drawings, which are incorporated in and form a part of the specification, illustrate embodiments of the presently disclosed invention and, together with the description, disclose the principles of the invention.
As shown in
As shown in
The turbine vane ID support body 14 may be formed from one or more struts 40 supporting the base 16. The struts 40 may have any appropriate configuration for passing cooling fluids through the turbine vane ID support body 14 and into the turbine vane 12. The struts 40 may form one or more cooling fluid flow channels 42 through the turbine vane ID support body 14.
The turbine vane ID support system 10 may also include a forward rail support arm 44 extending from the turbine vane ID support body 14. The forward rail support arm 44 may include one or more forward rail receiving slots 46 configured to slideably receive a forward turbine vane rail 26. The slots 46 may extend generally along a longitudinal axis 50 of the turbine vane ID support body 14.
As shown in
The turbine vane ID support system 10 may include a turbine vane ID forward rail seal system 24 extending from the turbine vane ID support body 14 to seal the turbine vane ID support body 14 to a turbine vane ID forward rail 26 of a turbine vane 12. In one embodiment, the turbine vane ID forward rail seal system 24 may be attached to the forward rail support arm 44. As shown in
The turbine vane ID support system 10 may include an aft rail support arm 64 extending from the turbine vane ID support body 14 aft of the forward rail support arm 44. The aft rail support arm 64 may extend from the base 16 and terminate within close proximity of an aft turbine vane rail 66 but offset a distance sufficient to avoid contact because of thermal expansion and vibration. A turbine vane ID aft rail seal system 68 may extend from the aft rail support arm 64 to seal the aft turbine vane rail 66 to the turbine vane ID support body 14. In one embodiment, the turbine vane ID aft rail seal system 68 may be formed from one or more aft rail seal cavities 70 in the aft rail support arm 64. An aft rail seal 72 may extend from the aft rail seal cavity 70 and terminate in a cavity 74 in the aft turbine vane rail 66. The aft rail seal 72 may be formed from any appropriate material.
During use, aero loads are applied to a pressure side 76 of the turbine vane 12. With the turbine vane 12 secured at the forward turbine vane rail 26, both the ID rails 46, 66 and OD rails remain axially seated unlike conventional systems in which aero loads often unseat the pressure side rail corner, which results in leakage and sawtoothing at the shroud leading edge.
The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of this invention. Modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of this invention.
Number | Name | Date | Kind |
---|---|---|---|
2625013 | Howard et al. | Jan 1953 | A |
4083648 | Asplund | Apr 1978 | A |
4883405 | Walker | Nov 1989 | A |
4907946 | Ciokajlo et al. | Mar 1990 | A |
5271714 | Shepherd et al. | Dec 1993 | A |
5343694 | Toborg et al. | Sep 1994 | A |
5591003 | Boyd et al. | Jan 1997 | A |
5868398 | Maier et al. | Feb 1999 | A |
6179560 | Kouris et al. | Jan 2001 | B1 |
6517313 | Rogers | Feb 2003 | B2 |
6530744 | Liotta et al. | Mar 2003 | B2 |
6637752 | Aksit et al. | Oct 2003 | B2 |
6637753 | Mohammed-Fakir et al. | Oct 2003 | B2 |
6652229 | Lu | Nov 2003 | B2 |
20030129055 | Leeke et al. | Jul 2003 | A1 |
20030161726 | Lu | Aug 2003 | A1 |
20040013519 | Correia et al. | Jan 2004 | A1 |
Number | Date | Country | |
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20080101927 A1 | May 2008 | US |