U.S. patent application number 13/683015 was filed with the patent office on 2014-05-22 for turbomachine with trapped vortex feature.
This patent application is currently assigned to GENERAL ELECTRIC COMPANY. The applicant listed for this patent is GENERAL ELECTRIC COMPANY. Invention is credited to Bryan Wesley Romig, Lucas John Stoia.
Application Number | 20140137560 13/683015 |
Document ID | / |
Family ID | 49552210 |
Filed Date | 2014-05-22 |
United States Patent
Application |
20140137560 |
Kind Code |
A1 |
Stoia; Lucas John ; et
al. |
May 22, 2014 |
TURBOMACHINE WITH TRAPPED VORTEX FEATURE
Abstract
A turbomachine with a trapped vortex feature includes a unibody
liner formed to define a flow path for combustion products, the
unibody liner including first and second portions defining first
radial planes, a third portion defining a second radial plane and
fourth and fifth portions extending substantially radially between
proximal ends of the first and third portions and proximal ends of
the second and third portions, respectively, and an injector
configured to deliver a fuel or a fuel/air mixture to a space
partially bound by the third, fourth and fifth portions.
Inventors: |
Stoia; Lucas John; (Taylors,
SC) ; Romig; Bryan Wesley; (Simpsonville,
SC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GENERAL ELECTRIC COMPANY |
Schenectady |
NY |
US |
|
|
Assignee: |
GENERAL ELECTRIC COMPANY
Schenectady
NY
|
Family ID: |
49552210 |
Appl. No.: |
13/683015 |
Filed: |
November 21, 2012 |
Current U.S.
Class: |
60/752 |
Current CPC
Class: |
F23R 2900/00015
20130101; F23R 3/28 20130101; F23R 3/346 20130101; F23R 3/286
20130101; F23R 3/20 20130101; F23R 2900/03041 20130101 |
Class at
Publication: |
60/752 |
International
Class: |
F23R 3/28 20060101
F23R003/28 |
Claims
1. A turbomachine with a trapped vortex feature, comprising: a
unibody liner formed to define a flow path for combustion products,
the unibody liner comprising: first and second portions defining
first radial planes, a third portion defining a second radial plane
and fourth and fifth portions extending substantially radially
between proximal ends of the first and third portions and proximal
ends of the second and third portions, respectively; and an
injector configured to deliver a fuel or a fuel/air mixture to a
space partially bound by the third, fourth and fifth portions.
2. The turbomachine according to claim 1, wherein the injector is
configured to deliver the fuel or the fuel/air mixture to the space
in a substantially axial direction.
3. The turbomachine according to claim 1, wherein the unibody liner
comprises a combustor liner and a transition piece liner and the
space is defined proximate to a connection of the combustor liner
and the transition piece.
4. The turbomachine according to claim 1, wherein the space has an
annular shape.
5. The turbomachine according to claim 1, wherein the space has a
substantially rectangular cross-sectional shape.
6. A turbomachine, comprising: a unibody liner formed to define a
flow path for combustion products; the unibody liner being formed
to define a trapped vortex feature into which a portion of
combustion products flow; and an injector configured to deliver a
fuel or a fuel/air mixture to the trapped vortex feature.
7. The turbomachine according to claim 6, wherein the injector is
configured to deliver the fuel or the fuel/air mixture to the
trapped vortex feature in a substantially axial direction.
8. The turbomachine according to claim 6, wherein the unibody liner
comprises a combustor liner and a transition piece liner and the
trapped vortex feature is defined proximate to a connection of the
combustor liner and the transition piece.
9. The turbomachine according to claim 6, wherein the trapped
vortex feature has an annular shape.
10. The turbomachine according to claim 6, wherein the trapped
vortex feature has a substantially rectangular cross-sectional
shape.
11. A turbomachine, comprising: a combustor liner defining a first
interior in which combustion occurs and a second interior through
which products of combustion flow; a transition piece liner
disposed downstream from the combustor liner, the transition piece
liner defining a third interior, which is receptive of the products
of combustion and through which the products of combustion continue
to flow, at least one of the combustor liner and the transition
piece liner being formed to define a recess into which a portion of
the products of combustion flow; and an injector configured to
deliver combustible materials to the recess whereby the combustible
materials and the portion of the products of combustion form
respectively trapped vortices.
12. The turbomachine according to claim 11, wherein the combustible
materials comprise fuel or a fuel mixed with compressor discharge
casing air.
13. The turbomachine according to claim 11, further comprising: a
flow sleeve disposed about the combustor liner to define a first
annulus; and an impingement sleeve disposed about the transition
piece liner to define a second annulus, the second annulus being
fluidly coupled to the first annulus.
14. The turbomachine according to claim 11, wherein the injector
comprises: a vane formed to define a flowpath by which air is
transmitted from a compressor discharge casing to the recess; and a
fuel source configured to provide a supply of fuel to the
flowpath.
15. The turbomachine according to claim 14, wherein the vane
comprises a micromixer.
16. The turbomachine according to claim 14, wherein the fuel source
comprises a flexible hose.
17. The turbomachine according to claim 11, wherein the injector is
configured to deliver the combustible materials to the recess in a
substantially axial direction.
18. The turbomachine according to claim 11, wherein the recess is
defined proximate to a connection of the combustor liner and the
transition piece liner.
19. The turbomachine according to claim 11, wherein the recess has
an annular shape.
20. The turbomachine according to claim 11, wherein the recess has
a substantially rectangular cross-sectional shape.
Description
BACKGROUND OF THE INVENTION
[0001] The subject matter disclosed herein relates to turbomachines
and, more particularly, to turbomachines with trapped vortex
features.
[0002] A typical turbomachine includes a compressor to compress
inlet air, a combustor in which the compressed inlet air is
combusted along with fuel, a turbine in which products of the
combustion are receivable for power generation purposes and a
transition piece. The transition piece is fluidly interposed
between the combustor and the turbine.
[0003] In some cases, the typical turbomachine is configured to
support axially staged or late lean injection. In these cases, fuel
and air are injected into downstream sections of the combustor or
the transition piece in order to cause secondary combustion within
the downstream sections of the combustor or the transition piece.
This secondary combustion tends to reduce emissions of pollutants,
such as oxides of nitrogen.
BRIEF DESCRIPTION OF THE INVENTION
[0004] According to one aspect of the invention, a unibody liner
formed to define a flow path for combustion products, the unibody
liner including first and second portions defining first radial
planes, a third portion defining a second radial plane and fourth
and fifth portions extending substantially radially between
proximal ends of the first and third portions and proximal ends of
the second and third portions, respectively, and an injector
configured to deliver a fuel or a fuel/air mixture to a space
partially bound by the third, fourth and fifth portions.
[0005] According to another aspect of the invention, a turbomachine
is provided and includes a unibody liner formed to define a flow
path for combustion products, the unibody liner being formed to
define a trapped vortex feature into which a portion of combustion
products flow, and an injector configured to deliver a fuel or a
fuel/air mixture to the trapped vortex feature.
[0006] According to yet another aspect of the invention, a
turbomachine is provided and includes a combustor liner defining a
first interior in which combustion occurs and a second interior
through which products of combustion flow, a transition piece
disposed downstream from the combustor liner, the transition piece
defining a third interior, which is receptive of the products of
combustion and through which the products of combustion continue to
flow, at least one of the combustor liner and the transition piece
being formed to define a recess into which a portion of the
products of combustion flow and an injector configured to deliver
combustible materials to the recess whereby the combustible
materials and the portion of the products of combustion form
respectively trapped vortices.
[0007] These and other advantages and features will become more
apparent from the following description taken in conjunction with
the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] 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:
[0009] FIG. 1 is a schematic illustration of a turbomachine;
and
[0010] FIG. 2 is an enlarged view of a portion of the turbomachine
of FIG. 1.
[0011] 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
[0012] With reference to FIGS. 1 and 2, a turbomachine 10 includes
a compressor 11 to compress inlet air, a combustor 12 in which the
compressed inlet air is combusted along with fuel, a turbine 13 in
which products of combustion are receivable for power generation
purposes and a transition piece 14. The transition piece 14 is
fluidly interposed between the combustor 12 and the turbine 13. The
turbomachine 10 is configured to support axially staged injection
or late lean injection (LLI) whereby fuel and air are injected into
downstream sections of the combustor 12 or the transition piece 14
in order to cause secondary combustion processes. This secondary
combustion tends to reduce emissions of pollutants, such as oxides
of nitrogen, from the turbomachine 10.
[0013] In some axially staged injection or LLI configurations, it
has been found that almost all of the air available for
turbomachine operations is utilized for combustion in one form or
another and that little to no air is bypassed in the form of
combustor dilution air. This means that air used for axially staged
injection or LLI robs the head end of the combustor 12 of some
portion of air that could have otherwise been used to improve head
end performance for a given amount of fuel. Accordingly, the
turbomachine 10 is provided with a trapped vortex feature (which is
described below) that allows most of the air available for
combustion to be provided through the pre-mixers at the head end of
the combustor 12 and then be re-utilized later for axially staged
injection or LLI.
[0014] With reference to FIG. 2, the combustor 12 includes a
combustor liner 20 and a flow sleeve 21. The combustor liner 20 is
formed to define a first interior 201, in which a first stage of
the combustion occurs, and a second interior 202. The products of
combustion flow through the second interior 202 toward the turbine
13. The first interior 201 is generally defined proximate to a head
end of the combustor 12 at an axially upstream location and the
second interior 202 is defined fluidly and axially downstream from
the first interior 201. The flow sleeve 21 is disposed about the
combustor liner 20 to define a first annulus 22.
[0015] The transition piece 14 is disposed fluidly and axially
downstream from the combustor 12 and includes a transition piece
liner 30 and an impingement sleeve 31. The transition piece liner
30 is formed to define a third interior 301, which is fluidly
interposed between the second interior 202 and an interior of the
turbine 13. Thus, the third interior 301 is receptive of the
products of combustion from the second interior 202 of the
combustor 12 and provides for a flow path along or through which
the products of combustion can continue to flow toward the turbine
13. The impingement sleeve 31 is disposed about the transition
piece liner 30 to define a second annulus 32. The second annulus 32
is fluidly coupled with the first annulus 22. The impingement
sleeve 31 is formed to define impingement holes 310.
[0016] For purposes of clarity and brevity, in the following
description and claims, the combustor liner 20 and the transition
piece liner 30 may be referred to separately or as a unibody liner.
Thus, it will be understood that a unibody liner includes at least
portions of both the combustor liner 20 and the transition piece
liner 30.
[0017] Compressed air is exhausted from the compressor 11 and
enters a compressor discharge casing (CDC). From an interior of the
CDC, the compressed air enters the second annulus 32 via the
impingement holes 310. The compressed air then flows from the
second annulus 32 through the first annulus 22 toward the head end
of the combustor 12 where the compressed air is mixed with fuel and
combusted.
[0018] In some cases, a portion of the compressed air entering the
second annulus 32 may be used as a coolant for the transition piece
liner 30 within the third interior 301. In such cases, the
transition piece liner 30 may include a flange 33 that is sealed to
the transition piece liner 30 by hula seal 34. The flange 33 is
formed to define a cooling path 35 by which the portion of the
compressed air can be delivered to the third interior 301 along an
interior surface of the transition piece liner 30.
[0019] At least one or both of the combustor liner 20 and the
transition piece liner 30 is formed to define a substantially
annular recess 40 proximate to a connection of the combustor liner
20 and the transition piece liner 30. The recess 40 acts as a
trapped vortex feature 41 that extends radially outwardly from the
second interior 202 and/or the third interior 301. Thus, as the
products of combustion travel downstream through the second
interior 202 and then through the third interior 301 as a main
flow, a portion of the products of combustion flow into the recess
40 with a flow pattern (i.e., a second trapped vortex 70) to be
described below. In accordance with embodiments, the portion of the
products of combustion include air provided through the pre-mixers
at the head end of the combustor 12 and which is to be re-utilized
in the recess 40/trapped vortex feature 41.
[0020] In being formed to define the recess 40, the at least one of
the combustor liner 20 and the transition piece liner 30 includes a
first axial portion 401, a second axial portion 402, a third axial
portion 403, a fourth radial portion 404 and a fifth radial portion
405 with the recess at least partially bounded by the third axial
portion 403, the fourth radial portion 404 and the fifth radial
portion 405. The first axial portion 401 may be disposed upstream
from the second axial portion 402. The first and second axial
portions 401 and 402 may have annular shapes while respectively
defining first radial planes, RP1, which may be but need not be
substantially similar to one another. The third axial portion 403
may have an annular shape and defines a second radial plane, RP2,
which is displaced radially outwardly from the first radial planes,
RP1, by a predefined amount. The fourth radial portion 404 and the
fifth radial portion 405 each extend substantially radially to
connect the first and second axial portions 401 and 402 to the
third axial portion 403. That is, the fourth radial portion 404
extends substantially radially between proximal ends of the first
axial portion 401 and the third axial portion 403 while the fifth
radial portion 405 extends substantially radially between proximal
ends of the second axial portion 402 and the third axial portion
403.
[0021] In accordance with embodiments, the recess 40 may have a
substantially rectangular cross-sectional shape. In accordance with
further embodiments, the corners of the recess 40 (i.e., the
connections between the first axial portion 401 and the fourth
radial portion 404, the fourth radial portion 404 and the third
axial portion 403, the third axial portion 403 and the fifth radial
portion 405 and the fifth radial portion 405 and the second axial
portion 402) may be rounded to facilitate smooth fluid flow into
and out of the recess 40.
[0022] The turbomachine 10 further includes an injector 50. The
injector 50 is configured to deliver combustible materials, such as
a fuel or a fuel and air mixture, to the recess 40. In so doing,
the combustible materials form a first trapped vortex 60 while the
portion of the products of combustion that have flown into the
recess 40 form the second trapped vortex 70. The combustible
materials may include, for example, fuel and a quantity of air
derived from the CDC. As such, the combustible materials have a
pressure, P.sub.CD, which is substantially similar to the pressure
in the CDC interior.
[0023] As shown, the combustible materials forming the first
trapped vortex 60 tend flow in a first vortical pattern and the
portion of the products of combustion forming the second trapped
vortex 70 tends to flow in a second vortical pattern. The first and
second vortical patterns may be substantially oppositely oriented.
Thus, as the first and second vortices 60 and 70 are adjacent to
one another, the respective fluids in each one mix along the shear
line 80 such that the combustible materials injected into the
recess 40 by the injector 50 auto-ignite due to the temperatures
and pressures of the portion of the products of combustion. The
respective fluids, including the auto-ignited combustible
materials, are then returned to the main flow and proceed to flow
toward the turbine 13.
[0024] With the auto-ignited combustible materials returned to the
main flow, axially staged injection or LLI processes may be
engaged. This allows for secondary combustion to occur with the
associated advantages in terms of reduced pollutant emissions, for
example, but without the need to deprive the head end of the
combustor 12 of any of the air necessary for a given amount of
fuel.
[0025] The injector 50 may include a vane 51 and a fuel source 52.
The vane 51 is formed to define a flowpath 510 by which the
compressed air is transmittable from the CDC to the recess 40. The
fuel source 52 may include a flexible hose 520 and is configured to
provide a supply of fuel to the flowpath 510. The vane 51 is
substantially radially oriented and traverses the first annulus 22
and/or the second annulus 32. The vane 51 may be cylindrical or
otherwise aerodynamically formed to generate as little a
disturbance as possible in compressed air moving through the first
annulus 22 or the second annulus 32. The vane 51 may include a
micromixer 511 that is formed to mix the combustible materials to
be injected into the recess 40 and to prevent or substantially
reduce the possibility of flameholding in the recess 40 or the vane
51.
[0026] For most of the radial length of the vane 51, the flowpath
510 is oriented substantially radially. At a radially inward
location, however, the vane 51 may be configured such that the
flowpath 510 runs along the axial dimension of the turbomachine 10.
In this way, the injector 50 is configured to inject the
combustible materials into the recess 40 in a substantially axial
direction thus facilitating the formation of the first trapped
vortex 60.
[0027] In accordance with further embodiments, the fifth radial
portion 405 may be formed to define through-hole 53 by which
compressed air may flow from the second annulus 32 into the recess
40. In this way, additional air may be provided to enhance the
combustion of the fuel injected by the injector 50. Moreover, since
the through-hole 53 is defined through the fifth radial portion
405, the through-hole has a substantially axial orientation whereby
the compressed air flowing through the through-hole 53 flows in the
axial direction and thereby facilitates the formation of the first
trapped vortex 60. It will be understood that a similar effect can
be achieved with the through-hole 53 defined through a downstream
section of the third axial portion 403. In this case, the
compressed air flowing into the recess flows in the radial
direction and again facilitates the formation of the first trapped
vortex 60.
[0028] 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.
* * * * *