U.S. patent application number 10/561279 was filed with the patent office on 2009-10-08 for blade and gas turbine.
Invention is credited to Fathi Ahmad, Tobias Buchal, Michael Dankert, Gernot Lang, Michael Scheurlen.
Application Number | 20090252612 10/561279 |
Document ID | / |
Family ID | 33395823 |
Filed Date | 2009-10-08 |
United States Patent
Application |
20090252612 |
Kind Code |
A1 |
Ahmad; Fathi ; et
al. |
October 8, 2009 |
Blade and gas turbine
Abstract
The invention relates to a turbomachine, in particular to a gas
turbine and to a method for accelerating a temperature modification
of a rotor shaft rotationally mounted in said turbomachine. The aim
of said invention is to develop a device and a method for the
turbomachine making it possible to reduce the size of a radial
split of the turbomachine in order to obtain greater degree of
efficiency. The inventive turbomachine comprises a rotor
rotationally mounted in the case of the turbomachine, a feeding
channel embodied in the rotor for introducing a fluid and an outlet
channel embodied in the rotor for removing said fluid. An inlet
orifice of the feeding channel is disposed further inside than the
outlet orifice of the outlet channel, and means influencing a
liquid flow is formed of an actuating device dependent on
centrifugal force. Methods for cooling the rotor only by
decelerating the gas turbine and for heating the turbomachine rotor
by heating fluid flowing therethrough are also disclosed.
Inventors: |
Ahmad; Fathi; (Kaarst,
DE) ; Buchal; Tobias; (Dusseldorf, DE) ;
Dankert; Michael; (Offenbach, DE) ; Lang; Gernot;
(Baesweiler, DE) ; Scheurlen; Michael; (Orlando,
FL) |
Correspondence
Address: |
Siemens Corporation;Intellectual Property Corporation
170 Wood Avenue South
Iselin
NJ
08830
US
|
Family ID: |
33395823 |
Appl. No.: |
10/561279 |
Filed: |
May 27, 2004 |
PCT Filed: |
May 27, 2004 |
PCT NO: |
PCT/EP04/05753 |
371 Date: |
March 31, 2009 |
Current U.S.
Class: |
416/241A ;
416/223A; 416/241B |
Current CPC
Class: |
F01D 5/147 20130101;
F05D 2230/61 20130101; F01D 5/282 20130101; B23P 15/04 20130101;
F01D 5/14 20130101; F01D 5/284 20130101 |
Class at
Publication: |
416/241.A ;
416/223.A; 416/241.B |
International
Class: |
F01D 5/14 20060101
F01D005/14 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 18, 2003 |
EP |
03013857.2 |
Claims
1-14. (canceled)
15. A blade for use in a turbomachine, comprising: a blade root; a
platform region; and a main blade part having a blade length from a
blade leading edge to a blade trailing edge and a blade height from
the platform region to a main blade part tip and that is formed
from at least one base body segment and in the region of at least
one of two blade edges and from at least one edge segment that is
connected in a positively locking manner to the base body segment,
wherein in that the positively locking connection is produced by
means of projections which are formed integrally on one of the
segments and are spaced apart from one another in the direction of
the blade height, with the other segment at least partially
arranged projecting in between the projections.
16. The blade as claimed in claim 15, wherein the base body segment
and the edge segment each have a plurality of projections with
recesses between the projections and in that the projections
arranged on one of the two segments project in a positively locking
manner into the opposite recesses in the other segment forming
positively locking toothing.
17. The blade as claimed in claim 15, wherein a pin-like holding
element that extends in the direction of the blade edge secures the
segments against relative movements by the holding element
penetrating transversely through the projections of both
segments.
18. The blade as claimed in claim 15, wherein the segments are made
from different materials.
19. The blade as claimed in claim 15, wherein at least one segment
is made from a particularly thermally conductive material.
20. The blade as claimed in claim 15, wherein at least one segment
is made from a material which is resistant to high
temperatures.
21. The blade as claimed in claim 15, wherein at least one segment
is made from a ceramic material.
22. The blade as claimed in claim 15, wherein at least one segment
is made from a metal and/or a metal alloy.
23. The blade as claimed in claim 15, wherein at least one segment
is made from a plastic material.
24. The blade as claimed in claim 15, wherein the segments are
coated.
25. The blade as claimed in claim 15, wherein at least one segment
has a cavity.
26. The blade as claimed in claim 25, wherein the cavity is filled
with a material that is different from the segment material.
27. The blade as claimed in claim 15, wherein the blade is designed
as a guide vane or as a rotor blade.
28. A gas turbine, comprising: a compressor element; a combustion
element; a turbine element, wherein the turbine element has a
plurality of blades, the blades comprising; a blade root, a
platform region, and a main blade part having a blade length from a
blade leading edge to a blade trailing edge and a blade height from
the platform region to a main blade part tip and that is formed
from at least one base body segment and in the region of at least
one of two blade edges and from at least one edge segment that is
connected in a positively locking manner to the base body segment,
wherein in that the positively locking connection is produced by
means of projections which are formed integrally on one of the
segments and are spaced apart from one another in the direction of
the blade height, with the other segment at least partially
arranged projecting in between the projections.
29. The gas turbine as claimed in claim 28, wherein the blades have
at least one segment that has a cavity.
30. The gas turbine as claimed in claim 29, wherein the cavity is
filled with a material that is different from the segment material.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is the US National Stage of International
Application No. PCT/EP2004/005753, filed May 27, 2004 and claims
the benefit thereof. The International Application claims the
benefits of European Patent application No. 03013857.2 EP filed
Jun. 18, 2003, both of the applications are incorporated by
reference herein in their entirety.
FIELD OF THE INVENTION
[0002] The invention relates to a blade for use in turbomachines,
having a blade root, a platform region and a main blade part, which
main blade part has a blade length from a blade leading edge to a
blade trailing edge and a blade height from the platform region to
a main blade part tip, and which is formed from at least one base
body segment and, in the region of at least one of the two blade
edges, from at least one edge segment which is connected in a
positively locking manner to the base body segment.
BACKGROUND OF THE INVENTION
[0003] A corresponding turbine blade of modular construction is
known from U.S. Pat. No. 4,786,234. The main blade part disclosed
in that document is composed of a plurality of components or
segments. In this case, the different segments are divided over the
blade height. In a variant, U.S. Pat. No. 4,786,234 shows a main
blade part which is divided in the direction of the blade length,
with in particular the leading edge and the trailing edge of the
main blade part being designed as separate, radially movable
components.
[0004] To apply, for example, the latter embodiment of U.S. Pat.
No. 4,786,234 to a guide vane with a base body segment and two
cast-on platforms, at least one of the two platforms must have an
opening through which the radially displaceable blade edge can be
pushed onto the main blade part. In this case, special design
measures, such as for example sealing measures in the transition
region between main blade part and platform, are required, and
these measures are disadvantageous for production and
operation.
[0005] The invention is therefore based on the object of providing
an alternative, simplified design of a modular blade while at the
same time increasing the service life. A further object of the
invention is to provide a turbomachine with reduced maintenance and
production costs.
SUMMARY OF THE INVENTION
[0006] The object relating to the blade is achieved by the features
of the claims. Advantageous configurations are given in the
subclaims.
[0007] As a solution, it is proposed that the positively locking
connection is produced by means of projections which are formed
integrally on one of the segments and are spaced apart from one
another in the direction of the blade height, with the other
segment at least partially arranged projecting in between the
projections.
[0008] This connection allows particularly simple fitting of the
blade trailing edge and/or the blade leading edge, since the edge
segments are formed such that they can be displaced transversely
with respect to the blade edge. Therefore, with the blade according
to the invention, the edge segment can be exchanged without having
to dismantle the blade, which shortens the repair time.
Furthermore, the modular structure allows the blade edges of the
main blade part, which are subject to higher stresses and are
accordingly more vulnerable, to be selectively exchanged. This
increases the service life of the base body segment, which is
subject to less wear. Furthermore, the exchangeable regions can be
deliberately matched to the mechanical and thermal demands, which
leads to cost savings.
[0009] Furthermore, the segmentation allows production of standard
segments for the individual blade sizes, with the result that,
based on use and wear, the costs can be reduced further by
standardization. It is in this context advantageous if the segments
have different dimensions, so that the regions of the individual
wear levels can be optimally combined. The connection can be
effected by a press fit, soldering, welding, adhesive bonding or
pinned connections. In this context, it is advantageous for the
segment connecting surfaces to be oriented horizontally and/or
vertically.
[0010] In an advantageous configuration, a particularly effective
connection can be achieved if the base body segment and the edge
segment each have a plurality of projections with recesses between
them. Then, the projections arranged on one of the two segments can
project in a positively locking manner into the opposite recesses
in the other segment, forming positively locking toothing. This
allows secure attachment of the blade edges in particular in the
case of rotor blades, since the centrifugal forces acting on the
edge segments in the radial direction during operation can be
compensated for by a segment connecting surface of the base body
segment running transversely with respect thereto.
[0011] According to a particularly advantageous configuration, a
holding pin which runs in the direction of the blade edge secures
the segments against relative movements by virtue of this holding
pin penetrating transversely through the projections of both
segments. The toothed arrangement of the projections results in
overlapping, intermeshing regions through which an aligned bore, in
which the holding pin is fitted, can extend.
[0012] A further advantageous configuration provides for the
segments which form the main blade part to be made from different
materials. This is advantageous since there are regions which are
subject to higher mechanical stress and regions which are subject
to higher thermal stresses, with the result that the main blade
part can be optimally matched in its segmented structure to the
individual wear conditions by virtue of the different materials.
According to further teaching of the invention, some of the
segments may be made from a particularly thermally conductive
material, and others may be made from a material which is resistant
to high temperatures.
[0013] Suitable materials in this context are ceramic material,
metals, metal alloys and plastics materials. In addition, further
teaching of the invention provides for the segments to be coated.
This allows the properties of the segments to be deliberately
influenced further.
[0014] To reduce weight, the segments may have cavities. These
cavities may in this case be filled with a material which is
different from the segment material. This material may, for
example, be foams. It is in this way possible to deliberately
influence strength properties of the segments.
[0015] It is expedient for the blade to be designed as a guide vane
or as a rotor blade. It is particularly advantageous for a blade of
this type to be used in a gas turbine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Further features and advantages of the invention will emerge
from the following description of the associated drawing, which
diagrammatically depicts an exemplary embodiment of a modular blade
edge of a main blade part for a turbomachine. In the drawing:
[0017] FIG. 1 shows a perspective view of a blade according to the
invention with a trailing edge segment,
[0018] FIG. 2 diagrammatically depicts a partial sectional view of
a blade according to the invention with a trailing edge
segment,
[0019] FIG. 3 shows a diagrammatic side view of a blade with an
alternative trailing edge segment,
[0020] FIG. 4 shows a perspective view of a blade according to the
invention with a leading edge segment, and
[0021] FIG. 5 shows a diagrammatic partial sectional view of a
blade according to the invention with a leading edge segment.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Turbomachines use blade stages, which comprise adjacent
rotor blades and guide vanes, to convert flow energy into rotary
energy and vice versa. The guide vanes are arranged on the machine
housing, while the rotor blades are directly connected to the
rotor.
[0023] A blade 1 according to the invention with a segmented
trailing edge is illustrated in FIGS. 1 to 3. The blade 1 itself
has a platform 2a and a main blade part 3 with a blade leading edge
4 and a blade trailing edge 5. A second platform 2b, which is
formed integrally at the upper end 5a of the main blade part 3, is
illustrated by dashed lines. The main blade part 3 is composed of a
base body segment 3b and a trailing edge segment 3c. As can be seen
at the upper end 5a of the main blade part 3, the base body segment
3b has a plurality of cavities 6 which, given sufficient strength,
are used to reduce the blade mass in order to lower the mechanical
and thermal stresses in operation. One or more cavities 6 may be
filled with a foam in order to increase the strength of the main
blade part 3.
[0024] In the region of the blade trailing edge 5, the trailing
edge segment 3c has projections 7 which are spaced apart over the
blade height H and engage in a positively locking manner in
recesses 8 arranged opposite them in the base body segment 3b, so
that the two segments 3b, 3c are in a positively locking toothed
engagement. The projections 7 and the recesses 8 extend over only
part of the blade height. A permanent connection can be produced by
a press fit or, after assembly, by soldering or welding. This
arrangement may also be suitable for rotor blades, since a segment
connecting surface 11 which is oriented transversely with respect
to the centrifugal force is present for the mountable trailing edge
segment 3c and serves as a counterpoint to the centrifugal forces
acting on the trailing edge segment 3c in operation.
[0025] FIG. 2 illustrates a pinned connection between the trailing
edge segment 3c and the base body segment 3b in partial section. In
the base body segment 3b there are recesses 8 which lie opposite
the further recesses 9 arranged in the trailing edge segment 3c,
with a pin-like holding segment 10 projecting into each of them.
For assembly, the holding segments 10 are inserted into the
trailing edge segment 3c, for example as a press fit, and are then
secured to the base body segment 3b in the same way by means of a
displacement oriented transversely with respect to the blade
trailing edge 5.
[0026] FIG. 3 shows a guide vane of alternative configuration for a
turbine with two platforms 2a, 2b, each arranged at the end of the
main blade part 3. A part of the main blade part 3 is designed as
an exchangeable trailing edge segment 3c at the blade trailing edge
5. The base body segment 3b of the blade 1 has a recess 8 between
two projections 7, in which the trailing edge segment 3c is
entirely inserted. The projections 7 and the trailing edge segment
3c, in order for the latter to be attached and/or secured, have a
pin-like holding element 10 penetrating through them in the
direction of the blade trailing edge 5, which holding element can
be introduced from the rear side of the platform 2b and can then be
welded to the platform 2b. As a result, the platform 2b, in the
region of the blade trailing edge 5, can merge into the base body
segment 3b as projection 7, so that a complex construction can be
avoided in this transition region and, by way of example, there is
no need for a sealing means. Of course, a construction of this type
can also be used for highly stressed blade leading edges 4 of a
blade 1. Furthermore, it is possible for both blade edges 12 of the
blade 1 to be simultaneously segmented in form.
[0027] Similar to FIGS. 1 and 2, the segmented structure of the
blade leading edge 4 with respect to the main blade part 3 is
illustrated in FIGS. 4 and 5. In this case, the connection between
a leading edge segment 3a and the base body segment 3b is produced
by means of toothing formed by projections 7 and recesses 8 in FIG.
4 and by means of a pinned connection with pin-like holding
segments 10 in FIG. 5.
[0028] Dividing the blade into a number of components makes it
possible to reduce the casting accuracy, which contributes to a
drop in costs. Furthermore, when refurbishing the guide vane, it is
possible to replace only the worn edge.
[0029] It is particularly advantageous for the segments to be
formed from different materials with different strength and thermal
conductivity properties, in order for the blade to be inexpensively
matched to the local requirements.
* * * * *