U.S. patent application number 11/001125 was filed with the patent office on 2005-10-06 for nozzle guide vanes.
Invention is credited to Self, Kevin P., Simms, Mark J..
Application Number | 20050220619 11/001125 |
Document ID | / |
Family ID | 30130196 |
Filed Date | 2005-10-06 |
United States Patent
Application |
20050220619 |
Kind Code |
A1 |
Self, Kevin P. ; et
al. |
October 6, 2005 |
Nozzle guide vanes
Abstract
A turbine nozzle guide vane with passages leading from a hollow
core to respective seal strip slots, to deliver cooling air to
abutment faces on each end of the vane.
Inventors: |
Self, Kevin P.; (Bristol,
GB) ; Simms, Mark J.; (Bristol, GB) |
Correspondence
Address: |
MANELLI DENISON & SELTER
2000 M STREET NW SUITE 700
WASHINGTON
DC
20036-3307
US
|
Family ID: |
30130196 |
Appl. No.: |
11/001125 |
Filed: |
December 2, 2004 |
Current U.S.
Class: |
416/174 |
Current CPC
Class: |
F01D 9/041 20130101;
F05D 2240/81 20130101; F01D 11/008 20130101 |
Class at
Publication: |
416/174 |
International
Class: |
F04D 029/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 12, 2003 |
GB |
0328952.7 |
Claims
We claim:
1. A turbine nozzle guide vane for a gas turbine engine, the nozzle
guide vane including a pair of platforms with an aerofoil extending
therebetween, seal strip slots provided on each end of each
platform characterised in that passages are provided extending
within the nozzle guide vane from the respective platforms to the
respective seal strip slots for delivering cooling air to the
respective abutment faces of the guide vanes.
2. A turbine nozzle guide vane according to claim 1, characterised
in that the passages extend from a main hollow core in the
respective platforms to the seal strip slots.
3. A turbine nozzle guide vane according to claim 2, characterised
in that the passages are inclined relative to the main hollow
core.
4. A turbine nozzle guide vane according to claim 1, characterised
in that a plurality of passages extend to each seal strip slot.
5. A turbine for a gas turbine engine, the turbine including a
plurality of nozzle guide vanes arranged in one or more rings,
characterised in that the nozzle guide vanes are according to claim
1.
6. A method of forming turbine nozzle guide vanes for a gas turbine
engine, the method including investment casting metal around a core
member, which core member defines openings in the guide vane,
subsequently removing the core member, characterised in that
projections on the core member define passages extending into where
seal strip slots are provided.
7. A method according to claim 6, characterised in that the seal
strip slots are machined into the nozzle guide vanes following
removal of the core member therefrom, so as to expose ends of said
passages in the slots.
Description
[0001] This invention concerns turbine nozzle guide vanes for gas
turbine engines, and a method of forming such nozzle guide
vanes.
[0002] Turbine nozzle guide vanes for gas turbine engines generally
comprise inner and outer platforms with an aerofoil extending
therebetween. Such guide vanes are formed as a plurality of
segments arranged in one or more rings around an engine. It is
necessary for a gap to be left between adjacent guide vanes to
allow for manufacturing tolerances and thermal expansion during
use. These gaps are conventionally sealed by providing cooperating
slots in each guide vane, with a metal seal strip extending in the
slots and between the segments.
[0003] Nozzle guide vanes are generally air cooled, and passages
can be provided in the platforms and aerofoil. It is generally
difficult however to cool the abutment faces between adjacent
vanes, and particularly due to the provision of the seal strips
extending therebetween. Higher engine gas temperatures are
generally now being used which make cooling of the nozzle guide
vanes increasingly important.
[0004] According to the present invention there is provided a
turbine nozzle guide vane for a gas turbine engine, the nozzle
guide vane including a pair of platforms with an aerofoil extending
therebetween, seal strip slots provided on each end of each
platform, and passages extending within the nozzle guide vane from
the respective platforms to the respective seal strip slots for
delivering cooling air to the respective abutment faces of the
guide vanes.
[0005] The passages preferably extend from a main hollow core in
the respective platforms to the seal strip slots.
[0006] The passages are preferably inclined relative to the main
hollow core. A plurality of passages preferably extend to each seal
strip slot.
[0007] The invention also provides a turbine for a gas turbine
engine, the turbine including a plurality of nozzle guide vanes
according to any of the preceding three paragraphs, the nozzle
guide vanes being arranged in one or more rings.
[0008] The invention yet further provides a method of forming
turbine nozzle guide vanes for a gas turbine engine, the method
including investment casting metal around a core member, which core
member defines openings in the guide vane, subsequently removing
the core member, wherein projections on the core member define
passages extending into where seal strip slots are provided.
[0009] The seal strip slots are preferably machined into the nozzle
guide vanes following removal of the core member therefrom, so as
to expose ends of said passages in the slots.
[0010] An embodiment of the present invention will now be described
by way of example only and with reference to the accompanying
drawings, in which:
[0011] FIG. 1 is a perspective view of a nozzle guide vane
according to the invention;
[0012] FIG. 2 is a perspective plan view of a core member usable in
forming the nozzle guide vane of FIG. 1;
[0013] FIG. 3 is a diagrammatic perspective side view of the core
member of FIG. 2;
[0014] FIG. 4 is a diagrammatic cross sectional side view of part
of the guide vane of FIG. 1; and
[0015] FIG. 5 is a diagrammatic end view of part of the guide vane
of FIG. 1.
[0016]
[0017] FIG. 1 shows a turbine nozzle guide vane 10. The vane 10 has
an outer platform 12 and an inner platform 14. An aerofoil 16
extends between the platforms 12, 14. Abutment faces 18 are
provided on the end of each of the platforms 12, 14, and seal strip
slots 20 are provided in the abutment faces 18.
[0018] FIGS. 2 and 3 show a ceramic core member 22 usable in
investment casting of the guide vane 10. The core member 22 has a
body 24 to define a main hollow core in the guide vane 10, and four
inclined projections 26 extending from the body 24 to define
passages 28 extending into the seal strip slots 20.
[0019] FIGS. 4 and 5 diagrammatically show the nozzle guide vane 10
in use. In FIG. 4 there is shown part of a seal strip 30 locating
in the seal strip slot 20. FIG. 4 shows part of an outer platform
12, and above the guide vane 10 as shown in the drawing would be
the coolant side at high pressure. Cooling air would be supplied
through the main hollow core 32 formed in the body 24 and would
then pass through the passages 28 into the seal strip slot 20. The
cooling air would generally pass under the seal strip 20 as shown
by the arrow, and pass across the abutment face 18 which would face
a similar nozzle guide vane 10, to beneath the guide vane 10 as
shown, which would be the hot gas side at a lower pressure than the
cooling air within the guide vane 10.
[0020] In use, the nozzle guide vane 10 would be formed by casting
an appropriate metal around the core member 22 in an appropriate
shape mould. Following casting the core member 22 would be
destroyed, for instance by leaching. The seal strip slots 20 would
then be formed by machining until the slot 20 exposes ends of the
passages 28. By inclining the projections 26 and hence passages 28,
it means that this machining operation will not affect the main
hollow core 32 of the guide vane 10.
[0021] There is thus described a nozzle guide vane which provides
for cooling of the abutment edge and is thus suitable for use at
high gas temperatures. No additional manufacturing processes or
steps are required in forming such a nozzle guide vane, and
therefore such guide vanes can readily be manufactured.
[0022] Various modifications may be made without departing from the
scope of the invention. For instance, a different number of
passages may be provided, and these may be of a different
shape.
[0023] Whilst endeavouring in the foregoing specification to draw
attention to those features of the invention believed to be of
particular importance it should be understood that the Applicant
claims protection in respect of any patentable feature or
combination of features hereinbefore referred to and/or shown in
the drawings whether or not particular emphasis has been placed
thereon.
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