BACKGROUND OF THE INVENTION
[0001] The subject matter disclosed herein relates to an injection apparatus and, more particularly,
to an injection apparatus for attachment to an outer vessel disposed about an inner
vessel formed to define a main flowpath.
[0002] A typical turbomachine, such as a gas turbine engine, includes a compressor, a combustor
and a turbine. The compressor compresses inlet gas to produce compressed gas, which
is transmitted to the combustor. Within the combustor, the compressed gas is mixed
with fuel and combusted to produce high temperature fluids. These high temperature
fluids are then directed to the turbine for power and/or electricity generation. In
some cases, a transition piece may be disposed between the combustor and the turbine
such that the high temperature fluids flow through the transition piece prior to entering
the turbine.
[0003] As a result of the process described above, pollutants, such as oxides of nitrogen
(NOx) may be produced and emitted to the atmosphere. Recently, efforts have been undertaken
to reduce pollutant production and emission. Such efforts include the development
of axially staged fuel injection systems, such as late lean injection (LLI) systems.
In LLI systems, a quantity of fuel and air are injected into the main flowpath through
the combustor or the transition piece downstream of the main combustion zone.
[0004] A problem with such systems, however, is that axially staged or LLI injectors must
be integrally mounted to the transition piece, which is a complicated process that
may lead to further assembly issues with the transition piece impingement sleeve.
BRIEF DESCRIPTION OF THE INVENTION
[0005] According to one aspect of the invention, an injection apparatus is provided and
includes an annular base defining an injection hole location and having a protrusion
about the injection hole location and a tubular body formed to define an injection
hole, the tubular body to be sealably fastened to the annular base and the protrusion
at the injection hole location such that the tubular body and the protrusion cooperatively
define a plenum, which is communicative with the injection hole.
[0006] According to another aspect of the invention, an injection apparatus for attachment
to an outer vessel disposed about an inner vessel formed to define a main flowpath
is provided. The injection apparatus includes an annular base to be fastened to the
outer vessel, the annular base defining an injection hole location and having a protrusion
about the injection hole location and a tubular body formed to define an injection
hole, the tubular body to be sealably fastened to the annular base and the protrusion
at the injection hole location such that the injection hole permits communication
between an exterior of the outer vessel and the main flowpath and the tubular body
and the protrusion cooperatively define a plenum, which is communicative with the
injection hole.
[0007] According to yet another aspect of the invention, an injection apparatus for attachment
to an outer vessel disposed about an inner vessel formed to define a main flowpath
is provided. The injection apparatus includes an annular base to be fastened to the
outer vessel, the annular base defining injection hole locations and having protrusions
about the injection hole locations and tubular bodies each formed to define an injection
hole and each to be sealably fastened to the annular bases and the protrusions at
each injection hole location such that at each injection hole location the corresponding
one of the injection holes permits communication between an exterior of the outer
vessel and the main flowpath and the corresponding one of the tubular bodies and the
corresponding one of the protrusions cooperatively define a plenum. The corresponding
one of the tubular bodies is further formed to define additional injection holes for
communication between the plenum and the injection hole.
[0008] These and other advantages and features will become more apparent from the following
description taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0009] Embodiments of the present invention will now be described, by way of example only,
with reference to the accompanying drawings in which:
[0010] A schematic side view of an injection apparatus in accordance with embodiments.
[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 the sole figure, an injection apparatus 10 is provided. The injection
apparatus 10 is attachable to an outer vessel 11, such as an impingement sleeve or
a flow sleeve of an exemplary turbomachine transition piece. The outer vessel 11 may
be disposed about an inner vessel 12, which may be the turbomachine transition piece
and may be formed to define a main flowpath 120. During turbomachine operations, high
temperature fluids are produced in a combustor and directed toward a turbine by way
of the turbomachine transition piece. The flow of the high temperature fluids thus
proceeds along the main flowpath 120 of the inner vessel 12. It is, however, to be
understood that the injection apparatus 10 may be attachable to other vessels in the
turbomachine and/or other systems. As an alternate example, the injection apparatus
10 may be attachable to a forward end of the impingement sleeve (i.e., proximate to
the axial injection flow sleeve), the aft end of the impingement sleeve or to a flow
sleeve of the combustor.
[0013] The injection apparatus 10 includes a ring-shaped or annular base 20 and a tubular
body 40. The annular base 20 is configured to be fastened to the outer vessel 11 by
one or more of bolting, welding, sealing and butt welding. The annular base 20 has
a first surface 21 that is formed to define an injection hole location 200 and a protrusion
25. The protrusion 25 protrudes from an interior facing surface 26 of the annular
base 20 and extends perimetrically about the injection hole location 200 such that
the protrusion 25 is axisymmetric about a centerline of the inner vessel 12. The protrusion
25 includes a first part 27 and a connector 30. The first part 27 protrudes from the
interior facing surface 26 such that the first part 27 is axisymmetric about the centerline
of the inner vessel 12. The connector 30 has a first end 31, which is configured to
be fastened by, for example, welding to a distal end of the protrusion 25 perimetrically
about the injection hole location 200, and a second end 32. The first end 31 and the
second end 32 supportively meet at bend 33, which may be angular or curved, such that
the second end 32 defines a secondary injection hole location 201, which may correspond
to the injection hole location 200.
[0014] In accordance with embodiments, the injection hole location 200 and the secondary
injection hole location 201 may be round or, in some cases, substantially circular.
Similarly, the protrusion 25, the connector 30 and the tubular body 40 may also have
round or, in some cases, substantially circular cross-sections (i.e., they may be
ring-shaped) in correspondence with the shape of the injection hole location 200 and
the secondary injection hole location 201.
[0015] The tubular body 40 has sufficient length to extend across an annulus defined between
the outer vessel 11 and the inner vessel 12 and has an interior facing surface 41
that is formed to define a tubular injection hole 400. The tubular body 40 is sealably
fastened to the first surface 21 of the annular base 20 at the injection hole location
200 by way of, for example, bolt 42 that engages with the annular base 20. The tubular
body 40 also has a protrusion 45 that may be sealably fastened to the second end 32
of the connector 30 at the secondary injection hole location 201. Seals 46, such as
o-rings or c-seals, may be sealably disposed between the tubular body 40 and the first
surface 21 and between the protrusion 45 and the second end 32 of the connector 30.
The tubular injection hole 400 permits fluid communication between an exterior of
the outer vessel 11 and the main flowpath 120.
[0016] In accordance with embodiments, at an inlet end of the tubular body 40, the tubular
body 40 may include a flange 47. The annular base 20 may include an exterior facing
surface 28 that faces radially outwardly and away from the main flowpath 120. This
exterior facing surface 28 may have a fastening surface 280 formed thereon at the
injection hole location 200 where the exterior facing surface 28 is machined to be
flat and/or smooth and therefore configured for mating with the flange 47. Where bolt
42 is employed to fasten the tubular body 40 to the annular base 20, the bolt 42 extends
through both the flange 47 and the fastening surface 280 of the exterior facing surface
28.
[0017] The tubular body 40, the connector 30, the protrusion 25 and the annular base 20
may cooperatively define a plenum 50. The tubular body 40 is further formed to define
an additional injection hole 401 for permitting fluid communication between an interior
of the plenum 50 and the tubular injection hole 400. The additional injection hole
401 may be defined as a plurality of additional injection holes 401, which are arrayed
about the tubular injection hole 400 of the tubular body 40 at the plenum 50. Separation
between adjacent additional injection holes 401 may be uniform or non-uniform.
[0018] Where the injection apparatus 10 is attachable to an impingement sleeve or another
similar feature of a turbomachine, the plenum 50 may be supplied with fuel and the
exterior of the outer vessel 11 may include compressed air, such as compressor discharge
air that is produced by a compressor of the turbomachine. In these cases, the compressed
air flows through the tubular injection hole 400 and entrains a flow of the fuel from
the plenum 50 into the tubular injection hole 400. The fuel is thereby mixed with
the compressed air and injected into the main flowpath 120 as a fuel/air mixture.
As such, the injection apparatus 10 may be employed as part of an axially staged injection
system of a turbomachine or, more particularly, as part of a late lean injection (LLI)
system of the turbomachine. In the latter case, the fuel/air mixture may be lean such
that combustion of the fuel/air mixture within the main flowpath 120 serves to reduce
the production and subsequent emission of pollutants, such as oxides of nitrogen (NOx).
[0019] The annulus defined between the outer vessel 11 and the inner vessel 12 is generally
supported by support structures 60, such as a-spacers arrayed about the inner vessel
12. In accordance with embodiments, these support structures 60 may be disposed between
an exterior facing surface of the inner vessel 12 and the interior facing surface
26 of the annular base 20.
[0020] In accordance with aspects of the invention, the injection hole location 200 (and
the accompanying structures as described above) may be provided as a plurality of
injection hole locations 200. In these cases, the plural injection hole locations
200 may be arrayed about the outer vessel 11 and the inner vessel 12 as non-axisymmetric
features. Separation between adjacent injection hole locations 200 may be uniform
or non-uniform. In accordance with an exemplary embodiment, four injection hole locations
200 may be clustered about respective lower portions of the outer vessel 11 and the
inner vessel 12.
[0021] 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.
1. An injection apparatus (10), comprising:
an annular base (20) defining an injection hole location (200) and having a protrusion
(25) about the injection hole location (200); and
a tubular body (40) formed to define an injection hole (400), the tubular body (46)
to be sealably fastened to the annular base (20) and the protrusion (25) at the injection
hole location (400) such that:
the tubular body (40) and the protrusion (25) cooperatively define a plenum (50),
which is communicative with the injection hole (400).
2. The injection apparatus according to claim 1, wherein the annular base (20) includes
an exterior facing surface (28) having a fastening surface (280) formed thereon at
the injection hole location (200).
3. The injection apparatus according to claim 1 or 2, further comprising seals (46) disposed
between the tubular body (40) and the annular base (20) and between the tubular body
(40) and the protrusion (25).
4. The injection apparatus of any of claims 1 to 3, further comprising:
a plurality of injection hole locations (200) and a plurality of protrusions (25)
about the injection hole locations (200) defined in the annular base (20); and
a plurality of tubular bodies (40) each formed to define an injection hole (400) and
each to be sealably fastened to the annular base (20) and the protrusions (25) at
each injection hole location (200),
the corresponding one of the tubular bodies (40) being further formed to define additional
injection holes (401) for communication between the plenum (50) and the injection
hole (400).
5. The injection apparatus according to claim 4, wherein the injection hole locations
(200) are non-uniformly separated from one another.
6. The injection apparatus according to claim 4, wherein the injection hole locations
(200) are clustered.
7. The injection apparatus according to any of claims 4 to 6, wherein the additional
injection holes (401) for each corresponding tubular body (40) are arrayed about a
circumference of the injection hole (200) defined by the corresponding tubular body
(40).
8. The injection apparatus of any of claims 1 to 7, for attachment to an outer vessel
(11) disposed about an inner vessel (120) formed to define a main flowpath (120),
wherein the annular base (20) is to be fastened to the outer vessel (11), and
the injection hole (400) permits communication between an exterior of the outer vessel
(11) and the main flowpath (120).
9. The injection apparatus according to claim 8, wherein the outer vessel (11) comprises
an impingement sleeve of a turbomachine transition piece.
10. The injection apparatus according to claim 8 or 9, wherein the plenum (50) is supplied
with fuel and the exterior of the outer vessel (11) comprises compressed air.
11. The injection apparatus according to claim 8, 9 or 10, wherein the annular base (20)
is fastened to the outer vessel (11) by one or more of bolting, welding, sealing and
butt welding.
12. The injection apparatus according to any of claims 8 to 11, further comprising support
structures (60) to support the annular base (20) on the inner vessel (12).