Patent Application
20180094816
The present disclosure generally pertains to a resonator, and is directed toward a resonator for an injector of a gas turbine engine.
Gas turbine engines include compressor, combustor, and turbine sections. During operation of the gas turbine engine combustion oscillations may damage or reduce the operating life of the components of the combustor. Combustion oscillations may be the result of resonance within the fuel injectors.
U.S. Pat. No. 8,789,372 to Johnson, et al. discloses a system that may include a turbine engine. The turbine engine may include a fuel nozzle. The fuel nozzle may include an air path. The fuel nozzle may also include a fuel path such that the fuel nozzle is in communication with a combustion zone of the turbine engine. Furthermore, the fuel nozzle may include a resonator. The resonator may be disposed in the fuel nozzle directly adjacent to the combustion zone.
The present disclosure is directed toward overcoming one or more of the problems discovered by the inventors or that is known in the art.
A fuel injector for a combustor of a gas turbine engine is disclosed herein. In embodiments, the fuel injector includes an injector head, a stem, a fuel passage, a fitting, a fuel inlet, and a resonator. The stem extends from the injector head and includes a fitting portion distal to the injector head. The fuel passage extends within the stem from the fitting portion towards the injector head. The fitting is joined to the fitting portion. The fuel inlet fluidly connects the fitting to the fuel passage. The resonator is integral to the stem. The resonator includes a resonator body and a resonator neck passage. The resonator body encloses a resonator cavity. The resonator neck passage fluidly connects the resonator cavity to the fuel passage adjacent to the fuel inlet at the fitting portion.
A method for retrofitting a fuel injector including an injector head and a stem extending from the injector head is also disclosed. In embodiments, the method includes machining a hole through the stem to a stem fuel passage adjacent a fuel inlet fluidly connected to the stem fuel passage. The fuel inlet is located at a fitting portion of the stem at an end of the stem opposite the injector head. The method also includes metallurgically bonding a resonator to the fitting portion. The resonator includes a resonator body forming a resonator cavity fluidly connected to the stem fuel passage adjacent to the fuel inlet at the fitting portion.
The systems and methods disclosed herein include a resonator for a fuel injector. In embodiments, the fuel injector includes a fuel passage with an inlet for providing fuel into the fuel passage. The resonator includes a resonator body that forms a resonator cavity and a resonator neck passage that fluidly connects the resonator cavity to the fuel passage where the fluid connection is adjacent to the fuel inlet. Connecting the resonator neck passage adjacent to the fuel inlet may minimize the resonance of the fuel between the fuel passage and the flame, which may reduce combustor oscillations and increase the operating life of the components in the combustor.
In addition, the disclosure may generally reference a center axis 95 of rotation of the gas turbine engine, which may be generally defined by the longitudinal axis of its shaft 120 (supported by a plurality of bearing assemblies 150). The center axis 95 may be common to or shared with various other engine concentric components. All references to radial, axial, and circumferential directions and measures refer to center axis 95, unless specified otherwise, and terms such as “inner” and “outer” generally indicate a lesser or greater radial distance from center axis 95, wherein a radial 96 may be in any direction perpendicular and radiating outward from center axis 95.
A gas turbine engine 100 includes an inlet 110, a shaft 120, a compressor 200, a combustor 300, a turbine 400, an exhaust 500, and a power output coupling 50. The gas turbine engine 100 may have a single shaft or a dual shaft configuration.
The compressor 200 includes a compressor rotor assembly 210, compressor stationary vanes (stators) 250, and inlet guide vanes 255. The compressor rotor assembly 210 mechanically couples to shaft 120. As illustrated, the compressor rotor assembly 210 is an axial flow rotor assembly. The compressor rotor assembly 210 includes one or more compressor disk assemblies 220. Each compressor disk assembly 220 includes a compressor rotor disk that is circumferentially populated with compressor rotor blades. Stators 250 axially follow each of the compressor disk assemblies 220. Each compressor disk assembly 220 paired with the adjacent stators 250 that follow the compressor disk assembly 220 is considered a compressor stage. Compressor 200 includes multiple compressor stages. Inlet guide vanes 255 axially precede the compressor stages.
The combustor 300 includes a combustion chamber 390 and one or more fuel injectors 310. The fuel injectors 310 may be upstream of the combustion chamber 390 and may be annularly arranged about center axis 95.
The turbine 400 includes a turbine rotor assembly 410 and turbine nozzles 450. The turbine rotor assembly 410 mechanically couples to the shaft 120. In the embodiment illustrated, the turbine rotor assembly 410 is an axial flow rotor assembly. The turbine rotor assembly 410 includes one or more turbine disk assemblies 420. Each turbine disk assembly 420 includes a turbine disk that is circumferentially populated with turbine blades. Turbine nozzles 450 axially precede each of the turbine disk assemblies 420. Each turbine disk assembly 420 paired with the adjacent turbine nozzles 450 that precede the turbine disk assembly 420 is considered a turbine stage. Turbine 400 includes multiple turbine stages.
The exhaust 500 includes an exhaust diffuser 510 and an exhaust collector 520. The power output coupling 600 may be located at an end of shaft 120.
The fittings 315 supply fuel to the fuel injector 310 from a fuel source. The flange 311 may be joined to the stem 320, such as by metallurgical bonding. The flange 311 may include mounting holes 312 for securing the fuel injector 310 to the gas turbine engine 100. The fuel tube 317 may form part of the flow path of the fuel to the injector head 330 and may connect between the stem 320 and the injector head 330.
The resonator 350 may be integral to the stem 320, such as unitary with the stem 320 or metallurgically bonded to the stem 320. In the embodiment illustrated in
The fuel injector 310 may include stem fuel inlets 316 where the fittings 315 connect to the stem fuel passages. The stem fuel inlets 316 may form a transition between the fitting and a fuel passage. The stem fuel inlets 316 may include a flow restrictor, such as an orifice or a filter. In the embodiment illustrated, the stem fuel inlets 316 are located in the fittings 315 adjacent to the stem fuel passages and are distal to the injector head 330.
The fuel injector 310 may also include plugs 326. Each stem fuel passage may be machined into the stem 320. The plugs 326 may be inserted into the stem fuel passages and joined to the stem 320, such as by metallurgical bonding, to cap the ends of the stem fuel passages distal to the injector head 330.
The resonator 350 may include a resonator body 352, a resonator cavity 353, and a resonator neck passage 351. The resonator body 352 may include a resonator base 354, a resonator wall 355, and a resonator cap 356. The resonator base 354 may be adjacent to, such as next to or adjoining, the fitting portion 325. In the embodiment illustrated, the resonator base 354 includes the plugs 326 for the stem fuel passages. The resonator wall 355 may extend from the resonator base 354 in the direction opposite the fitting portion 325. The resonator wall 355 may be a hollow tube, such as a round tube (hollow cylinder), a square tube, and the like. The resonator cap 356 may be located at the end of the resonator wall 355 opposite the resonator base 354.
The resonator base 354, the resonator wall 355, and the resonator cap 356 may be integral to each other and to the stem 320. In the embodiment illustrated, the resonator base 354 (other than the plugs 326) and the resonator wall 355 are unitary to the stem 320, such as formed in the same bar stock; the resonator cap 356 is joined to the resonator wall 355, such as metallurgically bonded to the resonator wall 355. In other embodiments, the resonator base 354 (other than the plugs 326) is unitary to the stem 320, while the resonator wall 355 is joined to the resonator base 354, such as metallurgically bonded to the resonator base 354; and the resonator cap 356 may be unitary or joined to the resonator wall 355.
The resonator body 352 including the resonator base 354, the resonator wall 355, and the resonator cap 356 may form and enclose the resonator cavity 353. In the embodiment illustrated, the resonator cavity 353 includes a cylindrical shape. In other embodiments, the resonator cavity 353 may include, inter alia, a cuboidal shape, a prismatic shape, a spheroidal shape, or a conical shape.
The resonator neck passage 351 extends from a fuel passage, such as a stem fuel passage or an injector head fuel passage, to the resonator cavity 353. In the embodiment illustrated, the resonator neck passage 351 extends from the pilot fuel passage 321. The resonator neck passage 351 may include, inter alia, a cylindrical shape, cuboidal shape, or prismatic shape. In the embodiment illustrated, the resonator neck passage 351 extends through the resonator base 354, such as through a plug 326. The resonator neck passage 351 may fluidly connect the resonator cavity 353 to a fuel passage adjacent to a fuel inlet, such as a stem fuel inlet 316 or an injector head fuel inlet.
In the embodiment illustrated in
The axis of the resonator tube 357 and the resonator body 352 may be aligned on the same axis along with the fuel passage. The fuel passage may not be coaxial to the stem 320. Thus, in embodiments, the axis of the resonator 350 and of the stem 320 may be offset.
In the embodiment illustrated in
Gas turbine engines may be suited for any number of industrial applications such as various aspects of the oil and gas industry (including transmission, gathering, storage, withdrawal, and lifting of oil and natural gas), the power generation industry, cogeneration, aerospace, and other transportation industries.
Referring to
Once compressed air 10 leaves the compressor 200, it enters the combustor 300, where it is diffused and fuel is added. Air 10 and fuel are injected into the combustion chamber 390 and combusted. An air and fuel mixture is supplied via fuel injector 310. Energy is extracted from the combustion reaction via the turbine 400 by each stage of the series of turbine disk assemblies 420. Exhaust gas 90 may then be diffused in exhaust diffuser 510, collected and redirected. Exhaust gas 90 exits the system via an exhaust collector 520 and may be further processed (e.g., to reduce harmful emissions, and/or to recover heat from the exhaust gas 90).
A resonance may be linked between the flame and a fuel passage in the fuel injector 310, which may result in combustor oscillations. Fluidly connecting the resonator 350 to a fuel passage in the fuel injector 310, such as a pilot fuel passage 321 or a fuel gallery 332, may counteract the resonance between the flame and the fuel passage and may reduce or prevent combustor oscillations.
Connecting the resonator 350 to a fuel passage adjacent to a fuel inlet of the fuel injector 310, such as the stem fuel inlet 316 or the injector head fuel inlet 318 may place the resonator neck passage 351 adjacent to an antinode of the linked resonance between the flame and the fuel passage, which may increase the overall effectiveness of the resonator 350 and further reduce combustor oscillations. Counteracting and reducing combustor oscillations may increase the durability and operating life of the combustor 300 and the various components of the combustor 300.
The method also includes metallurgically bonding the resonator 350 to the fitting portion 325 where the resonator 350 includes a resonator body 352 forming a resonator cavity 353 fluidly connected to the stem fuel passage adjacent to the stem fuel inlet 316 at the fitting portion 325 at step 620.
In some embodiments, step 620 includes metallurgically bonding a resonator wall 355 of the resonator body 352 to the fitting portion 325. In these embodiments, the resonator body 352 includes a resonator cap 356 integral to the resonator wall 355 and the hole 327 forms the resonator neck passage 351 that fluidly connects the resonator cavity 353 to the stem fuel passage adjacent to the stem fuel inlet 316.
In other embodiments, the resonator 350 includes a resonator tube 357 extending from the resonator body 352 and step 620 includes metallurgically bonding the resonator 350 to the fitting portion 325 includes inserting the resonator tube 357 into the hole 327 and metallurgically bonding the resonator tube 357 to the stem 320. In these embodiments, the resonator tube 357 includes the resonator neck passage 351 that fluidly connects the stem fuel passage to the resonator cavity 353.
The preceding detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. The described embodiments are not limited to use in conjunction with a particular type of gas turbine engine or a particular combustion chamber. Hence, although the present disclosure, for convenience of explanation, depicts and describes particular embodiments of the fuel injector and resonator for a combustion chamber, it will be appreciated that the fuel injector and resonator in accordance with this disclosure can be implemented in various other configurations, can be used with various other types of combustion chambers and gas turbine engines, and can be used in other types of machines. Further, the resonator may be used in conjunction with a pilot or main fuel passage and can be used with gas or liquid fuel passages. Any explanation in connection with one embodiment applies to similar features of other embodiments, and elements of multiple embodiments can be combined to form other embodiments. Furthermore, there is no intention to be bound by any theory presented in the preceding background or detailed description. It is also understood that the illustrations may include exaggerated dimensions to better illustrate the referenced items shown, and are not consider limiting unless expressly stated as such.
