Patent Application
20130170997
The present application and the resultant patent relate generally to a turbine nozzle for a gas turbine engine and more particularly relate to a turbine nozzle with a flow fence positioned on a suction side or elsewhere so as to limit radial now migration and turbulence.
In a gas turbine, many system requirements should be met at each stage of the gas turbine so as to meet design goals. These design goals may include, but are not limited to, overall improved efficiency and airfoil loading capability. As such, a turbine nozzle airfoil profile should achieve thermal and mechanical operating requirements for a particular stage. For example, last stage nozzles may have a region of significantly high losses near an outer diameter. These loses may be related to radial flow migration along an inward suction side. Such radial flow migration may combine with mixing losses so as to reduce blade row efficiency. As such, a reduction in radial now migration with an accompanying reduction in the total pressure loss should improve overall performance and efficiency.
There is thus a desire for an improved turbine nozzle design, particularly for a last stage nozzle. Such an improved turbine nozzle design should accommodate and/or eliminate radial flow migration and associated loses about the airfoil. Such a reduction in radial flow migration and the like should improve overall performance and efficiency. Overall cost and maintenance concerns also should he considered and addressed herein.
The present application and the resultant patent provide an example of a turbine nozzle. The turbine nozzle described herein may include an airfoil with a leading edge and a trailing edge and a flow fence extending from the leading edge to the trailing edge.
The present application and the resultant patent further provide an example of a turbine. The turbine described herein may include a number of stages with each of the stages including a number of nozzles and a number of buckets. Each of the buckets may include an airfoil with a leading edge, a trailing edge, and a flow fence extending therebetween.
The present application and the resultant patent further provide an example of a turbine nozzle airfoil. The turbine nozzle airfoil described herein may include a leading edge, a trailing edge, a pressure side, a suction side, and a flow fence extending from the leading edge to the trailing edge along the suction side. Other configurations may be used.
These and other features and improvements of the present application and the resultant patent will become apparent to one of ordinary skill in the art upon review of the following detailed description when taken in conjunction with the several drawings and the appended claims.
Referring now to the drawings, in which like numerals refer to like elements throughout the several views,
The gas turbine engine 10 may use natural gas, various types of syngas, and/or other types of fuels. The gas turbine engine 10 may be any one of a number of different gas turbine engines offered by General Electric Company of Schenectady, N.Y., including, but not limited to, those such as a 7 or a 9 series heavy duty gas turbine engine and the like. The gas turbine engine 10 may have different configurations and may use other types of components. Other types of gas turbine engines also may be used herein. Multiple gas turbine engines, other types of turbines, and other types of power generation equipment also may be used herein together.
The buckets 130, 160, 190 may be positioned in a circumferential array on a rotor 200 for rotation therewith. Likewise, the nozzles 120, 150, 180 may be stationary and may be mounted in a circumferential array on a casing 210 and the like. A hot gas path 215 may extend therethrough the turbine 100 for driving the buckets 130, 160, 190 with the flow of combustion gases 35 from the combustor 25. Other components and other configurations also may be used herein.
The nozzle 220 may have a flow fence 300 positioned about the airfoil 230. The flow fence 300 may be positioned near the tip 290 of the airfoil 230, i.e., the flow fence 300 may be positioned closer to the tip 290 than the platform 280. The flow fence 300 may extend outwardly from the leading edge 240 to the trailing edge 250 along the suction side 270. As is shown, the flow fence 300 may have a uniform thickness 330 across the suction side 270 from the leading edge 240 to the trailing edge 250. The flow fence 300 may smoothly blend into the leading edge 240 and the trailing edge 250. The flow fence 300 may extend in a largely linear direction 320 along the suction side 270 although other directions may be used herein. The flow fence 300 may have a largely V or U-shaped configuration 310 although other configurations may be used herein. Specifically, the flow fence 300 may have any size, shape, or configuration.
More than one flow fence 300 may be used herein. Although the flow fence 300 has been discussed in te s of the suction side 370, a flow fence 300 also may be positioned on the pressure side 260 and/or a number of flow fences 300 may be positioned along both the suction side 270 and the pressure size 260. The number, positioning, and configuration of the flow fences 300 thus may vary herein. Other components and other configurations may be used herein.
The use of the flow fence 300 about the nozzle 220 thus acts to direct the flow of combustion gases 35 in an axial direction so as to reduce the amount of radial flow migration. Reduction in the extent of the radial flow migration may be accompanied by a reduction in total pressure losses so as to improve overall blade row efficiency and performance. The flow fence 300 thus acts as a physical barrier to prevent such flow migration in that the flow fence 300 channels the flow in the desired direction. The use of the flow fence 300 also may be effective in reducing turbulence thereabout.
Numerous modifications on the flow fence 300 may be used herein. For example,
It should be apparent that the foregoing relates only to certain embodiments of the present application and the resultant patent. Numerous changes and modifications may be made herein by one of ordinary skill in the art without departing from the general spirit and scope of the invention as defined by the following claims and the equivalents thereof.
