COMBUSTOR CAP MOUNTING STRUCTURE FOR A TURBINE ENGINE
A mounting structure for mounting a combustor cap in a combustor of a turbine engine includes support struts that are connected between the combustor cap and a concentric combustor cap barrel flange. The support struts may have an airfoil shape to minimize wakes created in a flow of compressed air that is passing over the support struts. Also, the support struts may have an interior passageway that allows a portion of the compressed air to flow though the support strut. The flow of air passing through the support struts may also pass through corresponding vent apertures in the combustor cap barrel flange so that the flow of air passing through the support struts is delivered into a space between the exterior of the combustor cap barrel flange and a forward casing of the combustor.
A combustor for a turbine engine used in the power generation industry can include a combustor cap that is mounted adjacent a forward end of the combustor. A plurality of fuel nozzles are typically mounted to an end cover and pass through the combustor cap. Compressed air flows around the exterior periphery of the combustor cap, makes a 180° turn, and then flows through the fuel nozzles, where the air is mixed with fuel. The air-fuel mixture is then ignited downstream from the combustor cap.
A flow sleeve 102 is positioned inside the outer casing 106. A combustor liner 104 is mounted concentrically inside the flow sleeve 102. A forward end of the combustor liner 104 engages a hula seal 117 on the exterior circumference 114 of the combustor cap 110. A flow of compressed air from the compressor section of the turbine engine flows through the annular space 103 between the flow sleeve 102 and the combustor liner 104, as illustrated by the arrows appearing in
In addition, the combustor cap design illustrated in
In one aspect, the invention may be embodied in a combustor cap assembly for a turbine engine that includes a generally cylindrical combustor cap configured to receive at least one fuel nozzle, a generally cylindrical combustor cap barrel flange that surrounds an outer circumference of the combustor cap, and a plurality of support struts that mount the combustor cap to the combustor cap barrel flange. The support struts extend between the outer circumference of the combustor cap and an inner circumference of the combustor cap barrel flange. An interior passageway extends through an interior of each support strut.
In another aspect, the invention may be embodied in a support strut that is configured to mount a combustor cap to a combustor cap barrel flange of a combustor of a turbine engine. The support strut includes a main body having an inner end that is configured to be attached to the outer circumference of a combustor cap and an outer end that is configured to be attached to an inner circumference of a combustor cap barrel flange. Also, an interior passageway extends through the main body between an entrance aperture and an exit aperture.
The airfoil shape of the support struts 160 also help to minimize any flow losses that result from the flow of compressed air impinging on the structure used to attach the combustor cap 110 to the combustor cap barrel flange 150. Another benefit of the airfoil shape is that it helps to minimize wakes if the flow of compressed air has a tangential component (swirl). If the air coming from the annular space 103 is swirling, the background art A-frames tended to cause a large wake, as they essentially act like flat plates with an angle of attack. In contrast, when airfoil shapes are used for the support struts the air will tend to stay attached to the airfoil in moderate angles of attack (swirl) thereby minimizing wakes or flow deficits from the structure.
In alternate embodiments, the entrance aperture of a support strut could be located on portions of the sidewall of the support strut other than the leading edge. For example, the entrance aperture could be located on a portion of the sidewall between the leading and trailing edges.
In still other embodiments, multiple entrance apertures could be provided on multiple portions of the sidewall of the support strut. For example, multiple entrance apertures could be formed on the leading edge 161 of a support strut. In some embodiments, all of the entrance apertures would lead to the same interior passageway. In alternate embodiments, each entrance aperture could lead to a separate interior passageway.
Also, in the embodiments described above, the exit aperture is located on the outer end of the support struts. In alternate embodiments, the exit aperture could be located in different locations. Also, multiple exit apertures could be provided.
In an embodiment of a support strut having multiple entrance apertures and/or multiple exit apertures, multiple interior passageways may be provided.
In the embodiments described above, the support struts have a cross-sectional shape with a rounded leading edge and a tapered trailing edge. In alternate embodiments, the support strut could have alternate cross-sectional shapes. For example, the support struts could have a rectangular cross-sectional shape, with or without rounded edges. Alternatively, the support struts could have a circular or oval cross-sectional shape. Still other cross-sectional shapes are also possible, depending on design considerations.
In the embodiments described above, the leading and trailing edges of the support struts were angled with respect to the inner and outer ends. In alternate embodiments, the inner and outer ends could form right angles with the leading and trailing edges of the support struts. Also, in alternate embodiments, the leading and trailing edges may be angled such that the inner ends of the support struts extend further rearward than the outer ends.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements which are encompassed within the spirit and scope of the appended claims.
Claims
1. A combustor cap assembly for a turbine engine, comprising:
- a generally cylindrical combustor cap configured to receive at least one fuel nozzle;
- a generally cylindrical combustor cap barrel flange that surrounds an outer circumference of the combustor cap; and
- a plurality of support struts that mount the combustor cap to the combustor cap barrel flange and which extend between the outer circumference of the combustor cap and an inner circumference of the combustor cap barrel flange, wherein an interior passageway extends through an interior of each support strut.
2. The combustor cap assembly of claim 1, wherein vent apertures are formed in the combustor cap barrel flange at locations corresponding to where the support struts are attached to the combustor cap barrel flange, and wherein each vent aperture operatively communicates with the interior passageway of a corresponding support strut.
3. The combustor cap assembly of claim 2, wherein the interior passageway in each support strut extends between an entrance aperture located on a side surface of the support strut and an exit aperture that is formed on a portion of the support strut that abuts the combustor cap barrel flange.
4. The combustor cap assembly of claim 3, wherein the entrance aperture of each support strut is located on a leading edge portion of the support strut which is impacted by a flow of compressed air.
5. The combustor cap assembly of claim 3, wherein the support struts are mounted to the combustor cap barrel flange such that a flow of air can pass from the entrance aperture of each support strut, through the interior passageway, out the exit aperture of the support strut and through a corresponding vent aperture of the combustor cap barrel flange to a location adjacent an exterior circumference of the combustor cap barrel flange.
6. The combustor cap assembly of claim 1, wherein each support strut has an airfoil shape with a rounded leading edge and a tapered trailing edge.
7. The combustor cap assembly of claim 1, wherein a leading edge of each support strut is angled with respect to the outer circumference of the combustor cap and the inner circumference of the combustor cap barrel flange such that the portion of the leading edge that is coupled to the combustor cap is located further forward than the portion of the leading edge that is coupled to the combustor cap barrel flange.
8. The combustor cap assembly of claim 7, wherein each support strut has an airfoil shape with a rounded leading edge and a tapered trailing edge.
9. A support strut configured to mount a combustor cap to a combustor cap barrel flange of a combustor of a turbine engine, comprising:
- a main body having an inner end that is configured to be attached to the outer circumference of a combustor cap and an outer end that is configured to be attached to an inner circumference of a combustor cap barrel flange; and
- an interior passageway that extends through the main body between an entrance aperture and an exit aperture.
10. The support strut of claim 9, wherein the entrance aperture is located on a sidewall of the main body and the exit aperture is located on the outer end of the support strut.
11. The support strut of claim 10, wherein the entrance aperture is located on a leading edge of the main body.
12. The support strut of claim 9, wherein the main body has an airfoil shape with a rounded leading edge and a tapered trailing edge.
13. The support strut of claim 9, wherein the inner and outer ends are substantially parallel to one another, wherein a leading edge of the main body forms an oblique angle with the inner end, and wherein a trailing edge of the main body forms an acute angle with the inner end.
14. The support strut of claim 13, wherein the main body has an airfoil shape with a rounded leading edge and a tapered trailing edge.
15. The support strut of claim 14, wherein the entrance aperture is located on the leading edge of the main body and the exit aperture is located on the outer end of the main body.
Type: Application
Filed: Apr 23, 2012
Publication Date: Oct 24, 2013
Inventors: Christopher Paul Kenner (Woodruff, SC), Jason Stewart (Greer, SC)
Application Number: 13/453,320
International Classification: F23R 3/00 (20060101);