U.S. patent application number 15/521314 was filed with the patent office on 2017-10-26 for gas turbine combustor and gas turbine.
This patent application is currently assigned to KAWASAKI JUKOGYO KABUSHIKI KAISHA. The applicant listed for this patent is KAWASAKI JUKOGYO KABUSHIKI KAISHA. Invention is credited to Kohshi HIRANO, Yoshiharu NONAKA, Takeo ODA, Takahiro UTO.
Application Number | 20170307210 15/521314 |
Document ID | / |
Family ID | 56091560 |
Filed Date | 2017-10-26 |
United States Patent
Application |
20170307210 |
Kind Code |
A1 |
HIRANO; Kohshi ; et
al. |
October 26, 2017 |
GAS TURBINE COMBUSTOR AND GAS TURBINE
Abstract
Provided are a gas turbine combustor and a gas turbine, with
which the amount of NOx exhaust emissions from a diffuse
combustion-type duct burner can be reduced. A duct burner is
provided with cylindrical fuel injection nozzles and air holes. The
fuel injection nozzles are supported by an outside casing along
eight axial centers included within a plane orthogonal to a center
axis and arranged at equidistant intervals (45-degree intervals) in
the circumferential direction. Sets of eight fuel injection nozzles
are respectively constituted as single fuel injection nozzle rows,
four fuel injection nozzle rows being arrayed at prescribed spacing
along a direction of a center axis. The angular positions of the
fuel injection nozzles are arrayed so as to be shifted by a
half-pitch angle in opposing rows.
Inventors: |
HIRANO; Kohshi;
(Kakogawa-shi, Hyogo, JP) ; UTO; Takahiro;
(Kobe-shi, Hyogo, JP) ; ODA; Takeo; (Kobe-shi,
Hyogo, JP) ; NONAKA; Yoshiharu; (Kobe-shi, Hyogo,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KAWASAKI JUKOGYO KABUSHIKI KAISHA |
Hyogo |
|
JP |
|
|
Assignee: |
KAWASAKI JUKOGYO KABUSHIKI
KAISHA
Hyogo
JP
|
Family ID: |
56091560 |
Appl. No.: |
15/521314 |
Filed: |
November 25, 2015 |
PCT Filed: |
November 25, 2015 |
PCT NO: |
PCT/JP2015/082982 |
371 Date: |
April 24, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F23C 7/00 20130101; F23R
2900/00002 20130101; F23R 3/36 20130101; F23C 5/08 20130101; F23C
3/002 20130101; F23R 3/28 20130101; F23R 3/38 20130101; F23R 3/34
20130101; F23R 3/286 20130101 |
International
Class: |
F23C 5/08 20060101
F23C005/08; F23R 3/28 20060101 F23R003/28; F23R 3/38 20060101
F23R003/38; F23C 3/00 20060101 F23C003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 2, 2014 |
JP |
2014-244082 |
Claims
1. A combustor for use with a gas turbine engine, for mixing and
combusting a fuel with a compressed air introduced from a
compressor and supplying a generated combustion exhaust gas to a
gas turbine, comprising: a combustion cylinder forming a combustion
chamber therein; a premixed combustion type main burner disposed on
an upstream side of the combustion cylinder; and a plurality of
diffusion combustion type reheating burners disposed on a
downstream side of the main burner to extend through a peripheral
wall of the combustion cylinder for injecting a fuel from the
peripheral wall into the combustion chamber, the plurality of
reheating burners being aligned in a circumferential direction and
an axial direction of the combustion cylinder.
2. The combustor according to claim 1, wherein the plurality of
reheating burners in neighborhood arrays are disposed in a
staggered fashion in the circumferential direction.
3. The combustor according to claim 1, comprising a fuel header
configured to distribute the fuel to the plurality of reheating
burners.
4. The combustor according to claim 1, comprising a first fuel
header configured to distribute a first fuel mainly composed of
methane to a predetermined number of reheating burners among the
plurality of reheating burners, and a second fuel header configured
to distribute a second fuel composed of a hydrogen gas or a
hydrogen-containing gas to the remaining reheating burners.
5. A gas turbine engine comprising the combustor according to claim
1.
6. A gas turbine engine comprising the combustor according to claim
2.
7. A gas turbine engine comprising the combustor according to claim
3.
8. A gas turbine engine comprising the combustor according to claim
4.
1. A combustor for use with a gas turbine engine, for mixing and
combusting a fuel with a compressed air introduced from a
compressor and supplying a generated combustion exhaust gas to a
gas turbine, comprising: a combustion cylinder forming a combustion
chamber therein; a premixed combustion type main burner disposed on
an upstream side of the combustion cylinder; and a plurality of
diffusion combustion type reheating burners disposed on a
downstream side of the main burner to extend through a peripheral
wall of the combustion cylinder for injecting a fuel from the
peripheral wall into the combustion chamber, the plurality of
reheating burners being aligned in a circumferential direction and
an axial direction of the combustion cylinder.
2. The combustor according to claim 1, wherein the plurality of
reheating burners in neighborhood arrays are disposed in a
staggered fashion in the circumferential direction.
3. The combustor according to claim 1 or 2, comprising a fuel
header configured to distribute the fuel to the plurality of
reheating burners.
4. The combustor according to any one of claims 1 to 3, comprising
a first fuel header configured to distribute a first fuel mainly
composed of methane to a predetermined number of reheating burners
among the plurality of reheating burners, and a second fuel header
configured to distribute a second fuel composed of a hydrogen gas
or a hydrogen-containing gas to the remaining reheating
burners.
5. A gas turbine engine comprising the combustor according to any
one of claims 1 to 4.
Description
TECHNICAL FIELD
[0001] The present invention relates to a combustor for use with a
gas turbine engine and a gas turbine engine.
BACKGROUND
[0002] With regard to gas turbine engines, a strict environmental
standard has been established for an amount of nitrogen oxide
(hereinafter referred to as "NOx") contained in a gas exhausted
from the gas turbine engine.
[0003] The applicant of this application has proposed a combustor
for use with a gas turbine engine, which comprises a plurality of
premixed combustion type main burners arranged on an upstream side
(i.e., first combustion region) of a combustion chamber and a
plurality of diffusion combustion type reheating burners each
positioned on a downstream side (i.e., second combustion region) of
the combustion chamber to oppose an associated dilution air supply
opening, for introducing a combustion air into the combustion
chamber (see, for example, Patent Document 1).
PRIOR ART DOCUMENT
Patent Document
[0004] Patent Document 1: JP 8-210641 A
SUMMARY OF THE INVENTION
Technical Problem
[0005] Advantageously, the gas turbine combustor described in
Patent Document 1 has a reduced risk of backfire due to the
employment of the diffusion combustion type reheating burners.
However, an increase of the fuel flow rate may increase the fuel
concentration in the combustion region for the reheating burners
and the resultant combustion temperature, which disadvantageously
increases the amount of NOx emission.
[0006] It is therefore an object of the present invention to reduce
the amount of NOx emission from the diffusion combustion type
reheating burner in the gas turbine combustor and the gas turbine
with the structure described above.
[0007] A combustor for use with a gas turbine engine of the present
invention is a gas turbine combustor for mixing and combusting a
fuel with a compressed air introduced from a compressor and
supplying a generated combustion exhaust gas to a gas turbine,
comprising a combustion cylinder forming a combustion chamber
therein; a premixed combustion type main burner disposed on an
upstream side of the combustion cylinder; and a plurality of
diffusion combustion type reheating burners disposed on a
downstream side of the main burner to extend through a peripheral
wall of the combustion cylinder for injecting a fuel from the
peripheral wall into the combustion chamber, the plurality of
reheating burners being aligned in a circumferential direction and
an axial direction of the combustion cylinder.
[0008] According to this arrangement, since the main burner is of
the premixed combustion type, an amount of NOx in the
high-temperature combustion gas generated in a primary combustion
region on the upstream side of the combustion chamber is reduced.
Since the plurality of reheating burners are aligned in the
circumferential direction and the axial direction of the combustion
cylinder and the reheating fuel is distributed and supplied from
the reheating burners to the combustion chamber, a fuel flow rate
per reheating burner is reduced as compared to when the plurality
of reheating burners is arranged in alignment with the
circumferential direction. Therefore, the fuel concentration
becomes thinner in the combustion region of the reheating burners,
so that the combustion temperature of the reheating burners is
generally kept lower, and the amount of NOx in the combustion gas
can consequently be reduced.
[0009] The plurality of reheating burners in neighborhood arrays
may be disposed in a staggered fashion in the circumferential
direction.
[0010] According to this configuration, by arranging the reheating
burners in staggered fashion in the circumferential direction, the
combustion of the reheating burners arranged on the downstream side
is hardly affected by the combustion of the reheating burners
arranged on the upstream side, and the combustion of the reheating
burners on the downstream side can be stabilized.
[0011] The combustor may comprise a fuel header configured to
distribute the fuel to the plurality of reheating burners.
[0012] According to this configuration, the fuel can evenly be
distributed with a simple configuration to the plurality of
reheating burners.
[0013] The combustor may comprise a first fuel header configured to
distribute a first fuel mainly composed of methane to a
predetermined number of reheating burners among the plurality of
reheating burners, and a second fuel header distributing a second
fuel composed of a hydrogen gas or a hydrogen-containing gas to the
remaining predetermined number of reheating burners.
[0014] According to this configuration, the fuel can be distributed
with a simple structure to the plurality of reheating burners.
[0015] A gas turbine engine of the present invention includes any
one of the combustors described above. According to this
configuration, a gas turbine engine equipped with a combustor
capable of suppressing an amount of NOx emission can be
provided.
[0016] According to the present invention, the combustor and the
gas turbine engine are capable of reducing the amount of NOx
emission.
BRIEF DESCRIPTION OF DRAWINGS
[0017] FIG. 1 is a diagram schematically showing a general
construction of a gas turbine according to an embodiment of the
present invention.
[0018] FIG. 2 is a longitudinal sectional view of a combustor
according to an embodiment of the present invention.
[0019] FIG. 3A is an axial cross-sectional view of the combustor
taken along lines A-A in FIG. 2.
[0020] FIG. 3B is an axial cross-sectional taken along lines B-B in
FIG. 2.
[0021] FIG. 3C is an axial cross-sectional view of the combustor
taken along lines C-D in FIG. 2.
[0022] FIG. 3D is an axial cross-sectional taken along lines D-D in
FIG. 2.
[0023] FIG. 4 is a cross-sectional view of a modification of a
reheating burner (fuel injection nozzle).
DESCRIPTION OF THE EMBODIMENTS
[0024] With reference to the accompanying drawings, several
embodiments of a combustor of use with a gas turbine engine and a
gas turbine according to present invention will be described. The
following description merely shows embodiments of the invention and
is not intended to limit the present invention, an application
thereof, or a use thereof.
[0025] FIG. 1 is a schematic diagram of a general construction and
functions of the gas turbine engine. The gas turbine engine 1 has a
compressor 2 taking in atmospheric air to generate compressed air
200. The compressed air 200 is combusted together with fuel in the
combustor 3 to generate high-temperature high-pressure combustion
gas (hereinafter referred to as "combustion exhaust gas") 300. The
combustion exhaust gas 300 is supplied to a turbine 4 where it is
used for rotating a rotor 5. The rotation of the rotor 5 is
transmitted to the compressor 2 where it is used for generating the
compressed air (hereinafter referred to as "combustion air") 200.
The rotation of the rotor 5 is transmitted to, for example, a
generator 6 where it is used for electric generation.
[0026] FIG. 2 shows the combustor 3. In this embodiment, the
combustor 3 is a reverse-flow can-type combustor in which the
compressed air 200 supplied from the compressor (see FIG. 1) flows
in one direction (downward direction in FIG. 1) and the combustion
exhaust gas 300 flows in the opposite direction (upward direction
in FIG. 1). The combustor may be an annular type combustor in which
a plurality of fuel injection valves are provided at intervals in a
peripheral direction of the combustor.
[0027] The combustor 3 includes a combustion cylinder 34 and a
casing 35, both coaxially arranged on a central axis 302. A burner
unit 30 is mounted on the top of the combustion cylinder 34. The
combustion cylinder 34 defines thereinside a combustion chamber 33
for combusting fuel injected therein from the burner unit 30. The
combustion cylinder 34 is surrounded by a cylindrical casing 35 to
form between the combustion cylinder 34 and the casing 35 an
annular combustion air flow path 37 through which the combustion
air 200 supplied from the compressor flows. The casing 35 and the
combustion cylinder 34 support a plurality of reheating burners 36
on a downstream side of the burner unit 30.
[0028] In this embodiment, the burner unit 30 includes a premixing
type main burner 31 disposed along the central axis 302 for
injecting a premixed gas generated by mixing a fuel and the
combustion air 200 into the combustion chamber 33 and a diffusion
combustion type pilot burner 32 for directly injecting a fuel into
the combustion chamber 33. The main burner 31 is coaxially disposed
around the pilot burner 32. The main burner 31 and the pilot burner
32 communicate with a first fuel supply source 305 through pipes
304.
[0029] In this embodiment, the main burner 31 has an outer cylinder
310 and an inner cylinder 312 arranged coaxially along the central
axis 302. As shown, the inner cylinder 312 also serves as a
combustion air injection cylinder 322b of the pilot burner 32
described later. An annular space between the outer cylinder 310
and the inner cylinder 312 is used as a premixing flow path 314 for
mixing the fuel and the combustion air. The pilot burner 32
includes a fuel injection cylinder 322a extending along the central
axis 302 and the combustion air injection cylinder 322b coaxially
mounted on the fuel injection cylinder 322a, and a fuel injection
path (not shown) formed in the fuel injection cylinder 322a is
connected to the first fuel supply source 305 through the pipe 304b
including a flow regulating valve, so that by opening the flow
regulating valve at the start-up operation, a natural gas supplied
from the first fuel supply source 305 is injected into the
combustion chamber 33. An annular air flow path 324, which is
formed between the fuel injection cylinder 322a and the combustion
air injection cylinder 322b, is connected at one end thereof to the
combustion air flow path 37 and at the other end thereof to the
combustion chamber 33, so that the combustion air 200 supplied from
the compressor is injected into the combustion chamber 33.
[0030] The premixing flow path 314 has one end opened to the
combustion chamber 33 and the other end oriented radially outwardly
and opened to the combustion air flow path 37 through a plurality
of air intake ports 315. A plurality of primary fuel nozzles 316
ejecting a first fuel is arranged radially outside the air intake
ports 315. Although not shown, preferably, the air intake ports 315
and the associated primary fuel nozzles 316 are arranged at regular
intervals in the circumferential direction around the center axis
302.
[0031] The primary fuel nozzles 316, each having a plurality of
fuel injection holes (not shown) formed at a position facing the
air intake port 315 so as to eject the first fuel toward the air
intake port 315, are connected to the first fuel supply source 305
through the pipes 304a with a flow regulating valve. This allows
that, when the flow regulating valve is opened in the normal
operation, the fuel from the first fuel supply source 305 is
supplied from the air intake ports 315 to the premixing flow path
314 where the fuel is premixed with the combustion air 200 supplied
from the combustion air flow path 37 and then is injected into the
combustion chamber 33. In this embodiment, a plurality of swirl
vane members or swirlers 317 are provided in the air intake ports
315 to impart a swirling force to the combustion air 200 flowing
into the premixing flow path 314 so as to promote the premixing
with the first fuel.
[0032] The reheating burners 36, which are diffusion combustion
type burners, include cylindrical fuel injection nozzles 38 and air
holes 340. As shown in FIG. 3, the fuel injection nozzles 38 are
attached to both the casing 35 and the combustion cylinder 34 along
eight axial centers 360 included on respective planes orthogonal to
the central axis 302 and arranged at regular angles of 45 degrees
in the circumferential direction. In this embodiment, eight fuel
injection nozzles 38a-1 to 38a-8, 38b-1 to 38b-8, 38c-1 to 38c-8,
38d-1 to 38d-8 constitute respective fuel injection nozzle arrays,
and four fuel injection nozzle arrays 38a, 38b, 38c, 38d are
arranged at predetermined intervals along the direction of the
central axis 302 (see FIG. 2).
[0033] As shown in FIGS. 2 and 3, in this embodiment, upstream end
portions of the fuel injection nozzles 38a-1 to 38a-8, 38c-1 to
38c-8 constituting the fuel injection nozzle arrays 38a, 38c are
connected to first fuel headers 39a, 39c distributing the first
fuel to the fuel injection nozzles 38a-1 to 38a-8, 38c-1 to 38c-8.
The first fuel headers 39a, 39c are connected to the first fuel
supply source 305 through a pipe 306 with a flow regulating
valve.
[0034] Also, upstream end portions of the fuel injection nozzles
38b-1 to 38b-8, 38d-1 to 38d-8 constituting the fuel injection
nozzle arrays 38b, 38d are connected to second fuel headers 39b,
39d distributing a second fuel to the fuel injection nozzles 38b-1
to 38b-8, 38d-1 to 38d-8. The second fuel headers 39b, 39d are
connected to a second fuel supply source 307 through a pipe 308
including a flow regulating valve such that the first fuel and the
second fuel can be injected into the combustion chamber 33 by
opening the flow regulating valve in a high-load operation. The
first fuel is a gas containing 60 vol % or more hydrocarbons with
hydrogen gas equal to or less than 10 vol %, or a liquid containing
60 vol % or more hydrocarbons. The second fuel is a gas containing
50 vol % or more hydrogen. In this embodiment, a natural gas may be
an example of the first fuel and a hydrogen gas may be an example
of the second fuel.
[0035] The first and second fuel headers 39a, 39c, 39b, and 39d
extend annularly around the outer casing 35. The combustion
cylinder 34 has air holes 340 associated with the fuel injection
nozzles 38a-1 to 38a-8, 38b-1 to 38b-8, 38c-1 to 38c-8, and 38d-1
to 38d-8 so that a part of the compressed air 200 is introduced as
combustion air into the combustion chamber 33 around the fuel
injection nozzles 38a-1 to 38a-8, 38b-1 to 38b-8, 38c-1 to 38c-8,
and 38d-1 to 3d-8 (see FIGS. 2 and 3).
[0036] Features of the combustor 3 of this embodiment will
hereinafter be described. FIGS. 3A to 3D show cross sections taken
along lines A-A, B-B, C-C, and D-D and viewed in the direction of
arrows of FIG. 2. As shown in FIGS. 3A and 3C, the angular
positions of the eight fuel injection nozzles 38a-1 to 38a-8
constituting the fuel injection nozzle array 38a are coincident
with the angular positions of the eight fuel injection nozzles
38c-1 to 38c-8 constituting the fuel injection nozzle arrays
38c.
[0037] As shown in FIG. 3B, the angular positions of the eight fuel
injection nozzles 38b-1 to 38b-8 constituting the fuel injection
nozzle array 38b are shifted by a half-pitch angle (22.5 degrees)
relative to the angular positions of the eight fuel injection
nozzles 38a-1 to 38a-8, 38c-1 to 38c-8 of each of the facing fuel
injection nozzle arrays 38a, 38c.
[0038] As shown in FIG. 3D, the angular positions of the eight fuel
injection nozzles 38d-1 to 38d-8 constituting the fuel injection
nozzle array 38d are shifted by the half-pitch angle (22.5 degrees)
relative to the angular positions of the eight fuel injection
nozzles 38c-1 to 38c-8 of the facing fuel injection nozzle array
38c. Therefore, the fuel injection nozzles 38a-1 to 38a-8, 38b-1 to
38b-8, 38c-1 to 38c-8, 38d-1 to 38d-8 arranged in the neighborhood
arrays are in a staggered arrangement.
[0039] An operation of the combustor 3 so constructed will
hereinafter be described with reference to FIG. 2. As shown in the
drawing, when a gas turbine (not shown) is started, the flow
regulating valve is opened so that the first fuel (natural gas)
supplied from the first fuel supply source 305 through the piping
304b to the pilot burner 32 is injected into the combustion chamber
33. Subsequently, the first fuel is diffusively mixed in the
combustion chamber 33 with the combustion air 200 injected from the
annular air flow path 324 into the combustion chamber 33. The
mixture is then ignited by an ignition source not shown to form a
pilot flame from diffusion combustion.
[0040] When the gas turbine changes into a normal operation, the
first fuel from the first fuel supply source 305 through the pipes
304 to the primary fuel nozzles 316 and the combustion air 200
flowing in from the air intake ports 315 are mixed with each other
in the premixing flow path 314 to generate a premixed gas.
Subsequently, the premixed gas is injected from the premixing flow
path 314 and then ignited by the pilot flame in the combustion
chamber 33 and combusted in a primary combustion region S1 on the
proximal side of the combustion chamber 33. As described above, the
lean premixed gas is combusted, which results in that a combustion
flame temperature in the combustion chamber 33 is reduced and,
therefore, an amount of NOx in the combustion exhaust gas of the
main burner 31 is minimized.
[0041] When high-load combustion is requested to raise the output
of the gas turbine, the reheating burners 36 are operated.
Specifically, the first fuel is supplied to the first fuel headers
39a and 39c. The supplied first fuel is evenly distributed to the
eight fuel injection nozzles 38a-1 to 38a-8 constituting the fuel
injection nozzle array 38a and the eight fuel injection nozzles
38c-1 to 38c-8 constituting the fuel injection nozzle array 38c and
then injected into the flow of the combustion exhaust gas 300 from
outside thereof.
[0042] Similarly, the second fuel (hydrogen gas) supplied to the
second fuel headers 39b, 39d, is evenly distributed to the eight
fuel injection nozzles 38b-1 to 38b-8 constituting the fuel
injection nozzle array 38b and the eight fuel injection nozzles
38d-1 to 38d-8 constituting the fuel injection nozzle array 38d and
then injected into the flow of the combustion exhaust gas 300 from
outside thereof. The amount of and the ratio of the first fuel
(natural gas) and the second fuel (hydrogen gas) supplied are
appropriately determined in accordance with combustion
conditions.
[0043] As described above, the arrangement of the first fuel
headers 39a, 39c and the second fuel headers 39b, 39d allows the
intended fuel to be distributed evenly to the eight fuel injection
nozzles 38a-1 to 38a-8, 38b-1 to 38b-8, 38c-1 to 38c-8, 38d-1 to
38d-8 with a simple structure.
[0044] The first fuel injected from the fuel injection nozzles
38a-1 to 38a-8, 38c-1 to 38c-8 and the second fuel injected from
the fuel injection nozzles 38b-1 to 38b-8, 38d-1 to 38d-8 are
diffusively mixed with a portion of the combustion air 200 flowing
into the combustion chamber 33 through the air holes 340 from the
circumferences of the fuel injection nozzles 38a-1 to 38a-8, 38b-1
to 38b-8, 38c-1 to 38c-8, 38d-1 to 38d-8. Since the reheating fuels
(the natural gas and the hydrogen gas) are distributed and supplied
from the fuel injection nozzles 38a-1 to 38a-8, 38b-1 to 38b-8,
38c-1 to 38c-8, 38d-1 to 38d-8 into the combustion chamber 33, a
fuel flow rate of each of the reheating burners 36 is reduced.
Therefore, the fuel concentration becomes thinner in the combustion
region of the reheating burners 36 as compared to when a plurality
of the reheating burners 36 is arranged only in the circumferential
direction, so that the overall combustion temperature is kept lower
and, as a result, the amount of NOx in the combustion gas 300 which
may be dependent on the combustion temperature is minimized.
[0045] As described above, according to the embodiment of the
present invention the fuel injection nozzles 38a-1 to 38a-8, 38b-1
to 38b-8, 38c-1 to 38c-8, 38d-1 to 38d-8 in the neighborhood arrays
of the combustor 3 are arranged in the staggered fashion with
respect to the circumferential direction. With this arrangement,
the combustion of the reheating burners arranged on the downstream
side is hardly affected by the combustion of the reheating burners
arranged on the upstream side, which stabilizes the combustion of
the reheating burners on the downstream side. The angular positions
of the eight fuel injection nozzles 38a-1 to 38a-8, 38b-1 to 38b-8,
38c-1 to 38c-8, 38d-1 to 38d-8, constituting each of the four fuel
injection nozzles arrays 38a, 38b, 38c, and 38d may be the
same.
[0046] The combustion exhaust gas 300 increased by combustion of
the first and second fuels introduced from the reheating burners 36
is fed into the gas turbine and used for output adjustment of the
gas turbine.
[0047] The embodiment described above may be modified in various
ways. For example, in the above embodiment, the hydrogen gas is
injected as the second fuel from the fuel injection nozzles 38b-1
to 38b-8, 38d-1 to 38d-8. Since the hydrogen gas has the mass
considerably smaller than the mass of air (a mixture of oxygen and
nitrogen), the hydrogen gas simply applied to the flow of
combustion exhaust gas 300 from the side thereof may not reach a
mainstream (central portion) of the flow of the combustion exhaust
gas 300. Therefore, for example, as shown in FIGS. 4A and 4B, a
throttle part 40 may be formed at an opening in a downstream end
portion of each of the fuel injection nozzles 38b-1 to 38b-8 (38d-1
to 38d-8) to increase a kinetic energy at the time of ejection of
the hydrogen gas. With the arrangement, the hydrogen gas can
purposely be fed into the mainstream (central portion) of the flow
of the combustion product gas. As a result, a combustion flame
having uniform concentration distribution as a whole can be formed
in a secondary combustion region S2.
[0048] Although the first fuel is supplied to the fuel injection
nozzle arrays 38a, 38c and the second fuel is supplied to the fuel
injection nozzle arrays 38b, 38d in the configuration exemplified
in the embodiment described above, the present invention is not
limited thereto. The fuel headers can be produced in a proper
structure to employ a configuration such that, for example, the
first fuel is injected from the fuel injection nozzles 38a-1,
38a-3, 38a-5, 38a-7 out of the fuel injection nozzles 38a-1 to
38a-8 while the second fuel is injected from the remaining fuel
injection nozzles 38a-2, 38a-4, 38a-6, 38a-8 (the same applies to
the fuel injection nozzles 38b-1 to 38b-8, 38c-1 to 38c-8, 38d-1 to
38d-8 constituting the fuel injection nozzle arrays 38b, 38c,
38d).
[0049] Although the four fuel injection nozzle arrays 38a, 38b,
38c, 38d are arranged at predetermined intervals along the
direction of the center axis 302 in the exemplary embodiment
described above, the number of the fuel injection nozzle arrays may
be at least two or more, and the number can be changed as needed.
Although the fuel injection nozzles 38 are supported at eight
positions on the casing 35 on the outside at regular intervals
(intervals of 45 degrees) in the exemplary embodiment described
above, the number of the fuel injection nozzles 38 may be at least
two or more, and the number can be changed as needed. The pitch
angle shifting the angular position of the fuel injection nozzles
in the facing fuel injection nozzle arrays may also be changed in
accordance with the number of the fuel injection nozzles 38.
[0050] Although the first fuel is supplied to the first fuel
headers 39a, 39c and the second fuel is supplied to the second fuel
headers 39b, 39d in the exemplary embodiment described above, the
first fuel or the second fuel may be supplied to all of the first
fuel headers 39a, 39c and the second fuel headers 39b, 39d in
accordance with the invention.
PARTS LIST
[0051] 1 gas turbine [0052] 2 compressor [0053] 3 combustor [0054]
4 turbine [0055] 5 rotor [0056] 6 generator [0057] 31 main burner
[0058] 32 pilot burner [0059] 33 combustion chamber [0060] 34
combustion cylinder [0061] 36 reheating burner [0062] 37 combustion
air flow path (air flow path) [0063] 38 fuel injection nozzle
[0064] 38a to 38d fuel injection nozzle array [0065] 39a, 39c first
fuel header [0066] 39c, 39d second fuel header [0067] 40 throttle
part [0068] 200 compressed air (combustion air) [0069] 300
combustion exhaust gas [0070] 302 central axis [0071] 360 axial
center
* * * * *