US20140230447A1

US20140230447A1 - Fuel nozzle for a gas turbomachine

Info

Publication number: US20140230447A1
Application number: US13/771,614
Authority: US
Inventors: Heena Vinodkumar Panchasara; Gilbert Otto Kraemer
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2013-02-20
Filing date: 2013-02-20
Publication date: 2014-08-21

Abstract

A fuel nozzle for a gas turbomachine includes an outer nozzle body including an inner surface defining a mixing zone, and an inner nozzle body arranged within the outer nozzle body. The inner nozzle body includes a fluid passage. At least one flow affector extends from the inner nozzle body to the outer nozzle body. The at least one flow affector includes an inner surface that defines an interior chamber having an inlet fluidly connected to the fluid passage and at least two openings fluidically linking the interior chamber and the mixing zone. One or more flow tuning elements are arranged at the interior chamber upstream of the at least two openings. The one or more flow affectors are configured and disposed to condition a fluid passing into the interior chamber to affect a substantially iso-kinetic distribution of the fluid within the interior chamber.

Description

BACKGROUND OF THE INVENTION

The subject matter disclosed herein relates to the art of turbomachines and, more particularly, to a fuel nozzle for a gas turbomachine.
Gas turbomachines include a compressor portion linked to a turbine portion through a common compressor/turbine shaft and a combustor assembly. An inlet airflow is passed through an air intake toward the compressor portion. In the compressor portion, the inlet airflow is compressed through a number of sequential stages toward the combustor assembly. In the combustor assembly, the compressed airflow mixes with a fuel to form a combustible mixture. The combustible mixture is combusted in the combustor assembly to form hot gases. The hot gases are guided to the turbine portion through a transition piece. The hot gases expand through the turbine portion acting upon turbine blades mounted on wheels to create work that is output, for example, to power a generator, a pump, or to provide power to a vehicle.
The combustor assembly includes one or more fuel nozzles in which fuel, air, and/or diluents may be mixed to form a combustible mixture prior to combustion. In some cases, the fuel nozzle includes a number of internal vanes that enhance mixing of the combustible mixture. The internal vanes often times include internal passages that receive fuel and/or air to provide cooling to vane surfaces. The fuel and/or air may pass through openings in the vanes to mix with fuel and/or air passing over the vanes.

BRIEF DESCRIPTION OF THE INVENTION

According to one aspect of an exemplary embodiment, a fuel nozzle for a gas turbomachine includes an outer nozzle body including an inner surface defining a mixing zone, and an inner nozzle body arranged within the outer nozzle body and extending along the mixing zone. The inner nozzle body includes a fluid passage. At least one flow affector extends from the inner nozzle body to the inner surface of the outer nozzle body. The at least one flow affector includes an outer surface portion and an inner surface portion that defines an interior chamber having an inlet fluidly connected to the fluid passage and at least two openings fluidically linking the interior chamber and the mixing zone. One or more flow tuning elements are arranged at the interior chamber upstream of the at least two openings. The one or more flow affectors are configured and disposed to condition a fluid passing into the interior chamber to affect a substantially iso-kinetic distribution of the fluid within the interior chamber.
According to another aspect of an exemplary embodiment, a method of establishing an iso-kinetic distribution of fluid within a flow affector of a fuel nozzle for a gas turbomachine includes guiding a fluid flow into the fuel nozzle, passing the fluid flow into an interior chamber of the flow affector, conditioning the fluid flow in the interior chamber to establish an iso-kinetic fluid distribution within the interior chamber, and passing the fluid flow through at least two openings formed in the flow affector into a mixing zone. A pressure of the fluid flow passing from one of the at least two openings being substantially similar to a pressure of fluid flow passing from another of the at least two openings.
These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF DRAWINGS

The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic view of a gas turbomachine including a fuel nozzle in accordance with an exemplary embodiment;

FIG. 2 is a partial cross-sectional side view of the fuel nozzle in accordance with an exemplary embodiment;

FIG. 3 is a partial cross-sectional view of a flow affector including a flow tuning element in accordance with an aspect of the exemplary embodiment;

FIG. 4 is a partial cross-sectional view of a flow affector including a flow tuning element in accordance with another aspect of the exemplary embodiment;

FIG. 5 is a partial cross-sectional view of a flow affector including a flow tuning element in accordance with still another aspect of the exemplary embodiment;

FIG. 6 is a partial cross-sectional view of a flow affector including a flow tuning element in accordance with yet another aspect of the exemplary embodiment;

FIG. 7 is a partial cross-sectional view of a flow affector including a flow tuning element in accordance with yet still another aspect of the exemplary embodiment; and

FIG. 8 is a partial cross-sectional view of a flow affector including a flow tuning element in accordance with still yet another aspect of the exemplary embodiment.

The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.

DETAILED DESCRIPTION OF THE INVENTION

A gas turbomachine system in accordance with an exemplary embodiment is indicated generally at 2 in FIG. 1. Turbomachine 2 includes a compressor portion 4 fluidically connected to a turbine portion 6 through a combustor assembly 8. Combustor assembly 8 includes one or more combustors such as indicated at 10. Compressor portion 4 is also mechanically linked to turbine portion 6 through a common compressor/turbine shaft 12. With this arrangement, air enters an inlet (not separately labeled) of compressor portion 4 and is compressed through a number of compressor stages (not shown). A first portion of the air is passed to combustor assembly 8 and a second portion of the air is passed into turbine portion 6. The first portion of air is mixed with fuel in the one or more combustors 10. More specifically, air and fuel are introduced into one or more fuel nozzles 20 arranged in each combustor 10. Fuel nozzle 20 establishes a desired mixing of the fuel and air to form a combustible mixture. The combustible mixture is combusted in a combustion chamber (not shown) of each combustor 10 to form hot gases. The hot gases flow from combustor assembly 8 and into turbine portion 6 to produce work.
In accordance with an exemplary embodiment illustrated in FIG. 2, fuel nozzle 20 includes an outer nozzle body 24 and an inner nozzle body 25. Outer nozzle body 24 extends from a first end 26 to a second end 28 and includes an outer surface 30 and an inner surface 32. Inner surface 32 defines a mixing zone 34. Inner nozzle body 25 extends from a first end section 42 to a second end section 44 and includes an outer surface section 46 and an inner surface section 48 that defines an interior flow passage 50. A flow affector 60 extends between inner nozzle body 25 and outer nozzle body 24. In the exemplary embodiment shown, flow affector 60 takes the form of a vane 61 having an aerodynamic profile (not separately labeled) that affects or conditions fluid passing between inner nozzle body 25 and outer nozzle body 24. However, it should be understood that flow affector 60 may take on a variety of forms.
Flow affector 60 extends from a first end portion 62 coupled to outer surface section 46 of inner nozzle body 25 to a second end portion 63 coupled to inner surface 32 of outer nozzle body 24. Flow affector 60 includes an outer surface portion 66 and an inner surface portion 67 that defines an interior chamber 68 having an inlet 69. Flow affector 60 is also shown to include a first side portion 71 and a second, opposing side portion 72 (FIG. 3). First side portion 71 includes first and second openings 74 and 75 that fluidically interconnect interior chamber 68 and mixing zone 34. In further accordance with the exemplary aspect shown, inner nozzle body 25 includes a fluid passage 80 that extends from a first end 82 defining an inlet (not separately labeled) to a second end 84 positioned adjacent inlet 69 of interior chamber 68. As will be discussed more fully below, fluid passage 80 delivers a fluid through inner nozzle body 25 into flow affector 60. The fluid passes from first and second openings 74 and 75 to mix with another fluid in mixing zone 34.
Conventionally, fluid passing into a flow affector impacts internal surfaces creating a flow pattern that leads to a pressure differential being formed within the interior chamber. The pressure differential may create an irregularity in fluid flow pressure passing from inboard and outboard openings formed in the flow affector. Generally, the flow passing from the outboard opening is at a pressure that is greater than fluid passing from the inboard opening. The pressure difference may lead to inconsistences in fluid mixing that could lead to variations in combustor performance. In accordance with an exemplary embodiment the fluid passing into interior chamber 68 and/or fluid flowing within interior chamber 68 is tuned to form an iso-kinetic fluid distribution that facilitates a more even pressure drop at first and second openings 74 and 75.
As shown in FIG. 3, flow affector 60 includes a first flow tuning element 100 and a second flow tuning element 102 arranged at inlet 69 of interior chamber 68. First flow tuning element 100 takes the form of a first tuning vane 106 and second flow tuning element 102 takes the form of a second tuning vane 108. First and second tuning vanes 106 and 108 include first and second curvilinear surfaces 110 and 112 respectively. First and second tuning vanes 106 and 108 create flow patterns that lead to an iso-kinetic distribution of fluid within interior chamber 68. The iso-kinetic distribution of fluid leads to fluid pressure passing from first opening 74 to be substantially similar to fluid pressure passing from second opening 75. The similarity in output pressure leads to greater consistency in combustor performance.
FIG. 4, wherein like reference numbers represent corresponding elements in the respective views, illustrates a flow tuning element 120 in accordance with another aspect of the exemplary embodiment. Flow tuning element 120 takes the form of a plate 124 positioned across inlet 69. Plate 124 includes a plurality of passages 128. Passages 128 extend, in a substantially linear array, from an upstream end 130 to a downstream end 131 of plate 124. In accordance with an aspect of the exemplary embodiment each passage 128 includes a dimension that defines a diameter. Of course the dimension may define other geometries for passages 128.
In accordance with another aspect of the exemplary embodiment, the diameter of passages 128 taper from upstream end 130 to downstream end 131. More specifically, the one of passages 128 closest to upstream end 130 has a diameter that is greater than the one of passages 128 closest to downstream end 131. It should however be understood that the diameter of each passage 128 could be substantially identical. Passages 128 create flow patterns in fluid entering flow condition member 60 that lead to an iso-kinetic distribution of fluid within interior chamber 68. The iso-kinetic distribution of fluid leads to fluid pressure passing from first opening 74 to be substantially similar to fluid pressure passing from second opening 75. The similarity in output pressure leads to greater consistency in combustor performance.
FIG. 5, wherein like reference numbers represent corresponding elements in the respective views, illustrates a flow tuning element 140 in accordance with another aspect of the exemplary embodiment. Flow tuning element 140 takes the form of a plate 144 including an upstream end 146 and a downstream end 148. Plate 144 includes a tapered slot 150 that extends from upstream end 146 to downstream end 148. Tapered slot 150 includes a dimension (not separately labeled) at upstream end 146 that is greater than a dimension (also not separately labeled) at downstream end 148. Tapered slot 150 creates flow patterns in fluid entering flow affector 60 that lead to an iso-kinetic distribution of fluid within interior chamber 68. The iso-kinetic distribution of fluid leads to fluid pressure passing from first opening 74 to be substantially similar to fluid pressure passing from second opening 75. The similarity in output pressure leads to greater consistency in combustor performance.
FIG. 6, wherein like reference numbers represent corresponding elements in the respective views, illustrates a flow tuning element 160 in accordance with another aspect of the exemplary embodiment. Flow tuning element 160 take the form of a plurality of obstacles 162 that extend transversely across interior chamber 68. More specifically, obstacles 162 extend between first and second side portions 71 and 72. In the exemplary aspect shown, obstacles 162 include a non-circular or generally rectangular cross-section. The generally rectangular cross-section may be square. Obstacles 162 create flow patterns in fluid entering flow affector 60 that lead to an iso-kinetic distribution of fluid within interior chamber 68. The iso-kinetic distribution of fluid leads to fluid pressure passing from first opening 74 to be substantially similar to fluid pressure passing from second opening 75. The similarity in output pressure leads to greater consistency in combustor performance.
In FIG. 7, wherein like reference numbers represent corresponding elements in the respective views, illustrates a flow tuning element 168 in accordance with another aspect of the exemplary embodiment. Flow tuning element 168 is shown in the form of a plurality of obstacles 170 having a generally circular cross-section. More specifically, obstacles 170 extend between first and second side portions 71 and 72. Obstacles 170 create flow patterns in fluid entering flow affector 60 that lead to an iso-kinetic distribution of fluid within interior chamber 68. The iso-kinetic distribution of fluid leads to fluid pressure passing from first opening 74 to be substantially similar to fluid pressure passing from second opening 75. The similarity in output pressure leads to greater consistency in combustor performance.
FIG. 8, wherein like reference numbers represent corresponding elements in the respective views, illustrates a flow tuning element 180 in accordance with another aspect of the exemplary embodiment. Flow tuning element 180 takes the form of a wall section 182 that extends radially within interior chamber 68. More specifically, wall section 182 extends from first end portion 62 toward second end portion 63 within interior chamber 68. Wall section 182 includes a first scoop element 184 and a second scoop element 186 that impart flow characteristics to fluid entering into interior chamber 68 to facilitate an iso-kinetic distribution of fluid within interior chamber 68. The iso-kinetic distribution of fluid leads to fluid pressure passing from first opening 74 to be substantially similar to fluid pressure passing from second opening 75. The similarity in output pressure leads to greater consistency in combustor performance.
At this point it should be understood that the exemplary embodiments provide a fuel nozzle that includes flow tuning elements that establish an iso-kinetic distribution of fluid within an interior chamber of a flow affector. It should also be understood that the number, type, and geometry of the flow tuning elements may vary. Further, it should be understood that various flow tuning elements may be combined to establish a desired flow output. For example, obstacles having a generally rectangular cross-section may be combined with obstacles including a generally circular cross-section. Moreover, obstacles may be combined with tuning vanes, and plates to establish a desired flow output.
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

Claims

What is claimed is:

1. A fuel nozzle for a gas turbomachine comprising:

an outer nozzle body including an inner surface defining a mixing zone;

an inner nozzle body arranged within the outer nozzle body and extending along the mixing zone, the inner nozzle body including a fluid passage;

at least one flow affector extending from the inner nozzle body to the inner surface of the outer nozzle body, the at least one flow affector including an outer surface portion and an inner surface portion that defines an interior chamber having an inlet fluidly connected to the fluid passage and at least two openings fluidically linking the interior chamber and the mixing zone; and

one or more flow tuning elements arranged at the interior chamber upstream of the at least two openings, the at least one flow affector being configured and disposed to condition a fluid passing into the interior chamber to affect a substantially iso-kinetic distribution of the fluid within the interior chamber.

2. The fuel nozzle according to claim 1, wherein the one or more flow tuning elements comprise a first tuning vane arranged in the interior chamber and a second tuning vane arranged in the interior chamber and spaced from the first tuning vane.

3. The fuel nozzle according to claim 2, wherein each of the first and second tuning vanes includes a curvilinear surface.

4. The fuel nozzle according to claim 2, wherein the first tuning vane is positioned upstream of the at least two openings and the second tuning vane is positioned downstream of the at least two openings.

5. The fuel nozzle according to claim 1, wherein the one or more flow tuning elements constitutes a plate positioned across the inlet of the interior chamber, the plate including at least one passage fluidically connecting the fluid passage and the interior chamber.

6. The fuel nozzle according to claim 5, wherein the at least one passage comprises a tapered slot.

7. The fuel nozzle according to claim 5, wherein the at least one passage comprises a plurality of passages each having an associated dimension.

8. The fuel nozzle according to claim 7, wherein each of the plurality of passages includes an associated dimension that is different than others of the plurality of passages.

9. The fuel nozzle according to claim 8, wherein the dimension associated with each of the plurality of passages constitutes a diameter of each of the plurality of passages.

10. The fuel nozzle according to claim 1, wherein the one or more flow tuning elements comprises a plurality of obstacles extending transversely across the interior chamber.

11. The fuel nozzle according to claim 10, wherein the plurality of obstacles include a generally circular cross-section.

12. The fuel nozzle according to claim 10, wherein the plurality of obstacles includes a non-circular cross-section.

13. The fuel nozzle according to claim 1, wherein the one or more flow tuning elements include a wall section extending transversely across the interior chamber, the wall section including at least one scoop element formed in the wall section.

14. The fuel nozzle according to claim 1, wherein the at least one flow affector comprises a vane including an aerodynamic profile.

15. A method of establishing an iso-kinetic distribution of fluid within a flow affector of a fuel nozzle for a gas turbomachine, the method comprising:

guiding a fluid flow into the fuel nozzle;

passing the fluid flow into an interior chamber of the flow affector;

conditioning the fluid flow in the interior chamber to establish an iso-kinetic fluid distribution within the interior chamber; and

passing the fluid flow through at least two openings formed in the flow affector into a mixing zone, a pressure of the fluid flow passing from one of the at least two openings being substantially similar to a pressure of fluid flow passing from another of the at least two openings.

16. The method of claim 15, wherein conditioning the fluid flow includes passing the fluid flow across one or more flow tuning elements arranged at the interior chamber.

17. The method of claim 16, wherein passing the fluid flow across one or more flow tuning elements includes passing the fluid flow across one or more tuning vanes.

18. The method of claim 16, wherein passing the fluid flow across one or more flow tuning elements includes passing the fluid flow through at least one passage formed in a plate extending across an inlet of the interior chamber.

19. The method of claim 16, wherein passing the fluid flow across one or more flow tuning elements includes passing the fluid flow across one or more obstacles extending transversely across the flow affector.

20. The method of claim 16, further comprising: passing another fluid flow across an outer surface portion of the flow affector, the fluid flow passing from the at least two openings mixing with the another fluid flow downstream of the flow affector.