The present disclosure relates generally to gas turbine engines and, more particularly, to nosecones for gas turbine engines.
A gas turbine engine is a type of power plant commonly used for generating thrust for aircrafts, power for land or sea based operations, or other applications. A typical gas turbine engine includes an inlet section for drawing in a large mass of air, a compressor section for receiving and compressing the large mass of air to provide high-pressure air, a combustion section for mixing and combusting air and fuel, and a turbine section for receiving combustion gases and causing turbine blades to rotate to generate the aforementioned thrust or power.
The inlet section of the gas turbine engine may employ a nosecone assembly attached to a support structure, such as a support structure attached to a rotor. The nosecone assembly is generally constructed of multiple pieces of a very specific shape which are manufactured and assembled to tight tolerances to provide aerodynamic flow of air into the gas turbine engine. The nosecone assembly often includes a nosecone and a separate end cap attached to the nosecone. A support structure is provided to allow the cap to be bolted thereto. Due to the nosecone being constructed of a thin metal sheet, it is difficult to attach the nosecone to the support structure and the cap to the nosecone without warping or breaking the nosecone. Furthermore, conventional support structures can disrupt the aerodynamic flow of air around the nosecone. Such support structures can be relatively bulky, heavy, and expensive.
According to the present invention, a method includes connecting an inboard extending portion of a flange of a support ring to a gas turbine engine and sliding a nosecone into the support ring until a tip of a rim of the support ring hits a step at one end of a platform of the nosecone. The rim of the support ring is connected to the platform of the nosecone.
Another embodiment is a support ring for connecting a nosecone to a gas turbine engine. The support ring includes a rim and a flange. The rim has a conical surface that follows a curve of the nosecone. The rim has a hole extending radially therethrough to connect to the nosecone. The flange has a first portion with a wall resting on top of a platform of the nosecone. The first portion has a hole aligned with the hole in the rim to connect to the nosecone. The second portion extends substantially radially from the first portion and has a hole extending therethrough.
Another embodiment is a gas turbine engine including a nosecone, a gas turbine engine static support structure, and a support ring. The nosecone has a platform having a step on one end thereof. The support ring connects the nosecone to the gas turbine engine static support structure. The support ring has a rim having a curved surface following a curvature of the nosecone and a flange having an inboard extending portion. The rim is employed to connect to the nosecone. The inboard extending portion is employed to connect to the gas turbine engine static support structure.
Referring now to the drawings, and with specific reference to
In the illustrated embodiment, gas turbine engine 2 also includes compressor section 3B and turbine section 6B connected by shaft 4B. Compressor section 3A can be a low pressure compressor section, compressor section 3B can be a high pressure compressor section, turbine section 6B can be a high pressure turbine section, and turbine section 6A can be a low pressure turbine section. Shafts 4A and 4B are concentric and can rotate about centerline axis CL. Turbine section 6C is a power turbine section rotating independently from and positioned downstream of turbine sections 6A and 6B. Turbine section 6C may, for example, drive an electrical generator, pump, or gearbox (not shown).
Accordingly, it can be seen that, generally speaking, gas turbine engine 2 works by having compressor sections 3A and 3B draw in ambient air and compressing the same. That compressed air is then delivered to combustion chamber 5 where it is ignited, with the resulting hot combustion gases then being delivered to turbine sections 6A, 6B, and 6C. The hot expanding combustion gases cause the blades of turbine section 6A to rotate, and as they are mounted on the same shaft 4A as the blades of compressor section 3A, compressor section 3A rotates as well to create a self-sustaining cycle. Similarly, the hot expanding combustion gases cause the blades of turbine section 6B to rotate, and as they are mounted on the same shaft 4B as the blades of compressor section 3B, compressor section 3B rotates as well to create a self-sustaining cycle. The hot expanding combustion gases then flow downstream to cause the blades of turbine section 6C to rotate, driving the connected electrical generator, pump, gearbox, or other load.
Referring to
Gas turbine engine 2 may also include nosecone 10 connected to IGV inner shroud 7 via support ring 12, the details of which are shown more clearly in
Turning now to
As will be described below, rim 14 and first portion 20 of flange 16 may be employed for connecting to nosecone 10 and second portion 28 of flange 16 may be employed for connecting to IGV inner shroud 7. Furthermore, second portion 28 of flange 16 may extend in an inboard direction from edge 30 of first portion 20, as shown in
To facilitate the connection of nosecone 10 and support ring 12, rim 14 and first portion 20 of flange 16 may be formed with holes 32 at short intervals throughout the circumference of support ring 12, with each hole extending radially from rim 14 through wall 22 of the first portion for receiving a screw or bolt that connects rim 14 to nosecone 10, in a manner described below. (The terms screw and bolt will be used interchangeably herein, with either term being used to refer to both screws and bolts.) Similarly, second portion 28 of flange 16 may also be formed with holes 34 throughout its circumference at short intervals, with each hole facilitating connection of support ring 12 to IGV inner shroud 7, as also described below.
Support ring 12 may be positioned between and connected to nosecone 10, as well as IGV inner shroud 7. As shown in
After connecting support ring 12 to IGV inner shroud 7, nosecone 10 may be secured to support ring 12. In order to facilitate the connection of nosecone 10 and support ring 12, nosecone platform 24 may be formed with small step 46 (see
Specifically, as shown in
By virtue of utilizing a flush head screw 60 to connect nosecone 10 to support ring 12, a flush surface at the intersection of nosecone 10 and support ring 12 may be achieved and the disruption to the flow of inlet air around nosecone 10 may be minimized, thereby substantially preserving the aerodynamic flow of air into IGV inner shroud 7. Notwithstanding the fact that in the present embodiment, a flush head screw (e.g., screw 60) with anti-rotation capabilities has been employed for connecting nosecone 10 to support ring 12, in at least some embodiments, other types of screw or fastening mechanisms that may provide a flush surface with rim 14 and have anti-rotational capabilities may be employed as well. Furthermore, flexibility for thermal growth between the stiffer support ring 12 and nosecone 10 can be provided by scallops or tabs 62 as shown in
Referring now to
In the embodiment shown in
In the embodiment illustrated in
Holes 68 and 70 are positioned nearer nosecone tip 10A than nosecone aft end 10B. In the illustrated embodiment, holes 68 and 70 are positioned about one-third of the way from nosecone tip 10A to nosecone aft end 10B. By positioning holes 68 and 70 away from nosecone aft end 10B, holes 68 and 70 can be spaced from IGV assembly 11 to reduce the effect of holes 68 and 70 on air flowing through IGV assembly 11. Hole 68 is positioned substantially circumferentially opposite hole 70. In alternative embodiments, holes 68 and 70 can be positioned elsewhere on nosecone 10′ suitable for the application. In further alternative embodiments, nosecone 10′ can include fewer or more than two holes 68 and 70. For example, in one alternative embodiment, a single hole (not shown) could be positioned at nosecone tip 10A. Although holes 68 and 70 are shown on nosecone 10′, holes 68 and 70 can also be included on nosecone 10 (shown in
Even though support ring 12 is positioned radially outward of and in friction contact with nosecone 10′, removal tools 76 and 78 can pull nosecone 10′ away from support ring 12 without heating support ring 12 and without damaging nosecone 10′. In one embodiment, removal tools 76 and 78 can be rigid tools configured specifically for use with nosecone 10′. In other embodiments, removal tools 76 and 78 can be other tools suitable for the application.
In the illustrated embodiment, two removal tools 76 and 78 are inserted into two holes 68 and 70. In alternative embodiments, fewer or more than two removal tools 76 and 78 can be inserted into fewer or more than two holes 68 and 70. For example, in one alternative embodiment, removal tool 76 can be lengthened and can be inserted first into hole 68 and then into hole 70 so as to apply a pulling force to both holes 68 and 70. In another alternative embodiment, hole 68 can be positioned at nosecone tip 10A, hole 70 can be omitted, and removal tool 76 can be inserted into hole 68 for applying a pulling force to nosecone 10′ at nosecone tip 10A. In further alternative embodiments, three or more removal tools 76 and 78 can be inserted into three or more holes 68 and 70.
It will be understood that while the connection between nosecone 10 (or 10′) and support ring 12 has been described as following a certain order of steps (e.g., first connecting the support ring to the IGV inner shroud and then connecting the nosecone to the support ring), this order is merely exemplary.
The foregoing disclosure stands in contrast to prior art designs employing multiple pieces to form the nosecone and in so doing making assembly and disassembly more difficult, time-consuming and prone to damage. In addition, the single piece construction of the nosecone of the present disclosure eliminates welding and allows the nosecone to be formed from sheet stock material by spinning or pressing process, resulting in lower cost components. The nosecone assembly of the present disclosure can have relatively few gaps and recesses improving aerodynamic flow. Further, the nosecone assembly can be attached to an inner shroud of an inlet guide vane without an intervening structural support. Omitting a separate structural support can reduce cost, reduce weight, and improve aerodynamics of an industrial gas turbine engine. The nosecone assembly of the present disclosure can also facilitate relatively easy and efficient assembly and disassembly while reducing risk of damage.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
The following are non-exclusive descriptions of possible embodiments of the present invention.
A method for connecting a nosecone to a gas turbine engine can include providing a nosecone having a platform and a step at one end of the platform and providing a support ring having a rim and a flange having an inboard extending portion. The inboard extending portion of the flange can be connected to the gas turbine engine. The platform of the nosecone can be slid until a tip of the rim hits the step of the nosecone. The rim of the support ring can be connected to the platform of the nosecone.
A method can include connecting an inboard extending portion of a flange of a support ring to a gas turbine engine and sliding a nosecone into the support ring until a tip of a rim of the support ring hits a step at one end of a platform of the nosecone. The rim of the support ring can be connected to the platform of the nosecone.
The method of the preceding paragraph can optionally include, additionally and/or alternatively any, one or more of the following features, configurations and/or additional steps:
at least one hole in the inboard extending portion of the flange can be aligned with at least one hole in a wall of an inlet guide vane inner shroud and inserting a fastener therethrough;
connecting the rim of the support ring to the platform of the nosecone can include attaching a nutplate on a inner wall of the platform around a hole in the platform, aligning a hole in the rim of the support ring with the hole in the platform, and inserting a fastener through the hole in the rim and the hole in the platform;
a flush-head anti-rotational screw can be employed to fasten the rim to the platform;
the screw can be peened to provide further anti-rotation capability;
the rim can have a curved profile such that upon assembly, the rim follows the curved profile of the nosecone;
the platform of the nosecone can include a plurality of tabs, each of the plurality of tabs capable of connecting to the rim of the support ring; and/or
the support ring continues the smooth aerodynamic flow of air around the nosecone.
A support ring for connecting a nosecone to a gas turbine engine can include a rim and a flange. The rim can have a conical surface that follows a curve of the nosecone. The rim can have a hole extending radially therethrough to connect to the nosecone. The flange can have a first portion with a wall resting on top of a platform of the nosecone. The first portion can have a hole aligned with the hole in the rim to connect to the nosecone. The second portion can extend substantially radially from the first portion and can have a hole extending therethrough.
The support ring of the preceding paragraph can optionally include, additionally and/or alternatively any, one or more of the following features, configurations and/or additional components:
the first portion can have a substantially triangular section configuration;
the rim and the flange can be constructed as a single piece;
the support ring can provide support to the nosecone without high attachment stresses; and/or
the support ring can continue the aerodynamic flow of air around the nosecone.
A gas turbine engine can include a nosecone, a gas turbine engine static support structure, and a support ring. The nosecone can have a platform having a step on one end thereof. The support ring can connect the nosecone to the gas turbine engine static support structure. The support ring can have a rim having a curved surface following a curvature of the nosecone and a flange having an inboard extending portion. The rim can be employed to connect to the nosecone. The inboard extending portion can be employed to connect to the gas turbine engine static support structure.
The gas turbine engine of the preceding paragraph can optionally include, additionally and/or alternatively any, one or more of the following features, configurations and/or additional components:
the platform can include a plurality of tabs, the tabs being connected to the support ring;
the nosecone can be connected in between a nut plate on a bottom surface of the platform and the support ring on a top surface of the platform;
the rim can include a plurality of holes capable of being aligned with a plurality of holes on the platform when the support ring is slid against the nosecone;
the plurality of holes on the platform can be aligned with the plurality of holes on the rim when the platform step is slid against and up to the rim;
the rim and the flange of the support ring can be constructed as a single piece; and/or
the nosecone can be connected to the support ring using flush head screws having anti-rotational capability.
Filing Document | Filing Date | Country | Kind |
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PCT/US2013/076790 | 12/20/2013 | WO | 00 |
Number | Date | Country | |
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61746775 | Dec 2012 | US |