U.S. patent application number 10/221309 was filed with the patent office on 2003-03-13 for reinforcement and cooling structure of a turbine blade.
Invention is credited to Bolms, Hans-Thomas, Tiemann, Peter.
Application Number | 20030049125 10/221309 |
Document ID | / |
Family ID | 8168202 |
Filed Date | 2003-03-13 |
United States Patent
Application |
20030049125 |
Kind Code |
A1 |
Bolms, Hans-Thomas ; et
al. |
March 13, 2003 |
Reinforcement and cooling structure of a turbine blade
Abstract
The invention relates to a blade (13, 14) for a turbine (10)
which has at least one channel (22) that can be impinged with a
coolant fluid. Several turbulators (23) which improve the heat
exchange between the wall (19, 20) and the coolant fluid are
provided on at least one wall (19, 20) of the channel (22). In
addition, the turbulators (23) reinforce the wall (19; 20) and
converge. As a result of said reinforcement, the thickness (d) of
the wall (19, 20) in the area between the turbulators (23) can be
reduced.
Inventors: |
Bolms, Hans-Thomas;
(Muelheim, DE) ; Tiemann, Peter; (Witten,
DE) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O.BOX 8910
RESTON
VA
20195
US
|
Family ID: |
8168202 |
Appl. No.: |
10/221309 |
Filed: |
September 11, 2002 |
PCT Filed: |
March 15, 2001 |
PCT NO: |
PCT/EP01/02982 |
Current U.S.
Class: |
416/97R |
Current CPC
Class: |
F05D 2260/22141
20130101; F05D 2260/2212 20130101; F01D 5/187 20130101; F05D
2250/28 20130101; F01D 5/147 20130101 |
Class at
Publication: |
416/97.00R |
International
Class: |
F01D 005/08 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 22, 2000 |
EP |
00106246.2 |
Claims
1. A blade/vane, in particular a turbine blade/vane (13; 14),
having at least one duct (22), which is bounded by walls (19, 20,
21) and to which a cooling fluid can be admitted, a plurality of
turbulators (23) being provided on at least one wall (19; 20) to
improve the heat exchange between the wall (19; 20) and the cooling
fluid, characterized in that the turbulators (23) merge into one
another and are used to reinforce the wall (19; 20).
2. The blade/vane as claimed in claim 1, characterized in that the
turbulators (23) have a straight configuration.
3. The blade/vane as claimed in claim 2, characterized in that all
the turbulators (23a, 23b) include the same angle (.alpha., .beta.)
with a longitudinal center line (25) of the blade/vane (13;
14).
4. The blade/vane as claimed in claim 2 or 3, characterized in that
the turbulators (23a, 23b) include a right angle (26).
5. The blade/vane as claimed in claim 2, characterized in that a
first group of turbulators (23a) includes a first angle (.alpha.)
with a longitudinal center line (25) of the blade/vane (13; 14) and
a second group of turbulators (23b) includes a second angle
(.beta.) with the longitudinal center line (25) of the blade/vane
(13; 14).
6. The blade/vane as claimed in one of claims 2 to 5, characterized
in that the turbulators (23) are arranged in such a way that they
form recesses located adjacent to one another and above one another
in the form of polygons, in particular squares, rhombuses or
hexagons.
7. The blade/vane as claimed in one of claims 1 to 6, characterized
in that the wall thickness (d) of the wall (19; 20) is reduced, at
least in the region between the turbulators (23).
8. The blade/vane as claimed in one of claims 1 to 7, characterized
in that the blade/vane (13; 14) has a plurality of sections (28,
29, 30) provided with different arrangements of turbulators
(23).
9. The blade/vane as claimed in claim 8, characterized in that the
sections (28, 29, 30) are at a distance from one another.
10. The blade/vane as claimed in claim 8, characterized in that the
sections (28, 29, 30) merge into one another.
11. The blade/vane as claimed in one of claims 1 to 10,
characterized in that the blade is configured as a guide vane (13)
or as a rotor blade (14) of a turbomachine (10).
Description
[0001] The present invention relates to a blade/vane, in particular
a turbine blade/vane, having at least one duct, which is bounded by
walls and to which a cooling fluid can be admitted, a plurality of
turbulators being provided on at least one wall to improve the heat
exchange between the wall and the cooling fluid.
[0002] Such a turbine blade/vane is known, for example, from EP 0
758 932 B1. This known turbine blade/vane has a hollow
configuration and four ducts. The ducts are respectively bounded by
the two outer walls of the turbine blade/vane and by separating
walls and a cooling fluid flows through them for cooling purposes.
The outer walls are provided with turbulators in order to improve
the heat exchange between the outer walls and the cooling
fluid.
[0003] In the known turbine blades/vanes, the turbulators are only
used to improve the heat exchange. The loads on the turbine
blades/vanes occurring in operation are accepted, almost
exclusively, by the outer walls which must, in consequence, have a
relatively thick configuration. When the load is increased, the
wall thickness of the external walls must be further increased. Due
to this increase in the wall thickness, however, the cooling
efficiency, and therefore the overall efficiency, are reduced.
[0004] The object of the present invention is, therefore, to make
available a blade/vane which permits a higher load-carrying
capability without increasing the wall thickness or, alternatively,
permits a reduction in the wall thickness for the same
load-carrying capability.
[0005] In order to achieve this object, according to the invention,
in a blade/vane of the type mentioned at the beginning, provision
is made for the turbulators to merge into one another and to be
used to reinforce the wall.
[0006] According to the invention and for the first time, the
turbulators merge into one another and are used to reinforce the
walls. By this means, substantially increased reinforcement is
achieved without additional material and without increasing the
wall thickness. At the same time, good heat transfer is achieved
between the walls and the cooling fluid. There is, therefore, a
high cooling efficiency and a high overall efficiency. The
reinforcement of the wall does not only occur in the region of an
individual turbulator. The connection of the turbulators with one
another does, rather, make large-area reinforcement available.
[0007] Advantageous embodiments and developments of the invention
are given in the dependent claims. The turbulators have,
advantageously, a straight configuration. The use of straight
turbulators permits a high level of reinforcement in conjunction
with simple manufacture.
[0008] In an advantageous first embodiment, all the turbulators
include the same angle with a longitudinal center line of the
blade/vane. This provides a symmetrical arrangement of the
turbulators, which arrangement can accept the loads uniformly from
all directions.
[0009] In an advantageous development, the turbulators include a
right angle. As an alternative, an acute or obtuse angle can also
be selected.
[0010] According to an advantageous second embodiment, a first
group of turbulators includes a first angle with a longitudinal
center line of the blade/vane and a second group of turbulators
includes a second angle with the longitudinal axis of the
blade/vane.
[0011] The two groups of turbulators therefore have different
inclinations relative to the longitudinal center line of the
blade/vane. The reinforcement of the blade/vane therefore depends
on the angle of attack of the load. A specific matching of the
reinforcement in different directions can therefore be achieved by
the different inclinations.
[0012] The turbulators are advantageously arranged in such a way
that they form recesses located adjacent to one another and above
one another in the form of polygons, in particular squares,
rhombuses or hexagons. The inner surface of the wall is provided
with a honeycomb structure. The individual polygons or honeycombs
respectively form a closed, highly loadable cross section and
mutually support one another. A substantial increase in the
reinforcement can be achieved.
[0013] In an advantageous development, the thickness of the wall is
reduced, at least in the region between the turbulators. This
reduction in the wall thickness is made possible by the fact that
the turbulators effect a reinforcement of the wall. The cooling
efficiency is further increased by the reduction in the wall
thickness. During the casting of the blade/vane, the turbulators
can, in this arrangement, be advantageously used as metal feed
ducts. The honeycomb structure can therefore be easily
manufactured.
[0014] According to an advantageous embodiment, the blade/vane has
a plurality of sections provided with different arrangements of
turbulators. The reinforcement of the blade can be specifically
influenced in the individual sections by these different
arrangements. The result is optimum matching to the loads present
in the individual section of the blade/vane.
[0015] In an advantageous, first development, the sections are at a
distance from one another. This permits a simple transition between
different arrangements of turbulators.
[0016] According to a second advantageous development, the sections
merge into one another. There is a continuous increase in the
reinforcement of the blade/vane.
[0017] The blade/vane according to the invention can be configured
as a guide vane or as rotor a blade of a turbomachine.
[0018] The invention is described in more detail below using
exemplary embodiments, which are diagrammatically represented in
the drawing. The same designations are used throughout for similar
or functionally identical components. In the drawing:
[0019] FIG. 1 shows a longitudinal section through a
turbomachine;
[0020] FIG. 2 shows a perspective, exploded representation of a
blade/vane;
[0021] FIG. 3 shows an enlarged representation of the detail X from
FIG. 2;
[0022] FIG. 4 shows an end view onto the inner surface of an outer
wall of the blade/vane, in a first embodiment;
[0023] FIG. 5 shows a view similar to FIG. 4 in a second
embodiment;
[0024] FIG. 6 shows a view similar to FIG. 4 in a third
embodiment;
[0025] FIG. 7 shows a diagrammatic representation of a rotor blade;
and
[0026] FIG. 8 shows a diagrammatic representation of a guide
vane.
[0027] FIG. 1 shows a longitudinal section through a turbomachine
in the form of a turbine 10 with a casing 11 and a rotor 12. The
casing 11 is provided with guide vanes 13 and the rotor 12 is
provided with rotor blades 14. In operation, fluid flows through
the turbine 10 in the arrow direction 15, which fluid flows along
the guide vanes 13 and rotor blades 14 and sets the rotor 12 into
rotation about a center line 16.
[0028] In many applications, the temperature of the fluid is
relatively high, particularly in the region of the first blading
row (shown on the left in FIG. 1). For this reason, cooling is
provided for the guide vanes 13 and rotor blades 14. The flow of
the cooling fluid is diagrammatically indicated by the arrows 17,
18. Air, in particular, can be used as the cooling fluid.
[0029] FIG. 2 shows, diagrammatically, an exploded representation
of a guide vane 13. The guide vane 13 has curved outer walls, 19,
20. The internal space located between the outer walls 19, 20 is
subdivided into a total of three ducts 22 by means of two
separating walls 21. In operation, a cooling fluid is admitted to
the ducts 22.
[0030] In order to improve the heat exchange between the outer
walls 19, 20 and the cooling fluid, the outer walls 19, 20 are
provided with a plurality of turbulators 23. For reasons of drawing
representation, the turbulators 23 in FIG. 2 are represented in an
extremely simplified manner. It can, however, be seen that the
turbulators 23 merge into one another and form a honeycomb
structure. This honeycomb structure produces reinforcement of the
outer walls 19, 20.
[0031] FIG. 3 shows an enlarged representation of the detail X from
FIG. 2. The turbulators 23 have a straight configuration and merge
into one another. In the exemplary embodiment represented, each
recess 24 is bounded by four turbulators. The wall thickness d of
the outer wall 19 is continually reduced, starting from the
turbulators 23, as far as the center of the recess 24. This
reduction in the wall thickness d is made possible because the
turbulators 23 support one another and, by this means,
substantially increase the reinforcement of the guide vane 13. At
the same time, the turbulators 23 act as an impact protection.
[0032] Because of the reduced wall thickness d, the cooling
efficiency is increased. In consequence, less cooling fluid is
required so that a higher overall efficiency of the turbine 10 can
be achieved.
[0033] The turbulators 23 have an approximately triangular
configuration in cross section and taper, starting from the outer
wall 19. During the casting of the guide vane 13, therefore, they
can be used as metal feed ducts. The guide vane 13 according to the
invention is, therefore, easy to manufacture.
[0034] FIGS. 4 to 6 show a diagrammatic end view onto the inside of
the outer wall 19, in three different embodiments. In the
embodiment of FIG. 4, all the turbulators 23a, 23b include the same
angle .alpha., .beta., with a center line 25 of the guide vane 13.
The turbulators 23a, 2b include, between them, a right angle 26.
The recesses 24 bounded by the turbulators 23a, 23b therefore form
squares.
[0035] A turbulator 23a, 23b extends between two contact points 31
in each case. In the region of the contact points 31, the
turbulators 23a, 23b merge into one another. The use of straight
turbulators 23a, 23b simplifies the manufacture. In addition,
increased reinforcement is produced.
[0036] In the embodiment of FIG. 5, a first group of turbulators
23a includes a first angle .alpha. with the longitudinal center
line 25, whereas a second group of turbulators 23b includes a
second angle .beta. with the longitudinal axis 25. In this
embodiment, the angle 26 between the turbulators is greater than
90.degree.. The result, correspondingly, is a recess 24 in the form
of a rhombus. The different inclination of the turbulators 23a, 23b
relative to the longitudinal axis, results in a different
reinforcement of the guide vane 13, depending on the direction of
the load.
[0037] Good matching to different boundary conditions is therefore
achieved.
[0038] In the embodiment of FIG. 6, six turbulators 23 form a
recess 24 in the form of a hexagon in each case. The result is a
honeycomb structure which substantially increases the reinforcement
of the guide vane 13.
[0039] Other appropriate arrangements of turbulators 23 can, of
course, be used. The turbulators 23 are advantageously arranged in
such a way that the recesses 24 represented in FIGS. 4 to 6 are
produced. In the end view, these recesses 24 have a closed cross
section and, therefore, a high level of reinforcement. As an
alternative, the turbulators 23 can also be arranged in the form of
a V or X.
[0040] The turbulators 23 can also, of course, be provided in the
case of a rotor blade 14. FIG. 7 shows, diagrammatically, such a
rotor blade 14, which has a plurality of sections 28, 29, 30
provided with different arrangements of turbulators 23. The
arrangement of the section 28 corresponds, in this case, to the
representation of FIG. 4, whereas the sections 29, 30 correspond to
the configurations of FIGS. 5 and 6. The individual sections 28,
29, 30 are at a distance from one another. Cross-sectional and
shape changes of the rotor blade 14 can be undertaken, with little
manufacturing outlay, in the region between the sections 28, 29,
30. In order to achieve the necessary reinforcement, the wall
thickness d of the outer walls 19, 20 is correspondingly increased
in these transition regions. The use of different arrangements of
turbulators 23 permits the reinforcement of the blade 14 to be
specifically influenced in the individual sections 28, 29, 30. The
result is, therefore, optimum matching to different boundary
conditions along the longitudinal center line 25.
[0041] The sections 28, 29, 30 can also merge into one another, as
is diagrammatically represented using a guide vane 13 in FIG. 8. In
this case, the turbulators 23 of the individual sections 28, 29, 30
merge into one another at contact points (not represented in any
more detail). The result, therefore, is a continuous reinforcement
of the guide vane 13 along its longitudinal center line 25.
[0042] The present invention permits an increase in the
reinforcement by means of a specific arrangement of the turbulators
provided to improve the heat exchange. For the same load, the wall
thickness d of the outer walls 19, 20 can be reduced. The cooling
efficiency is increased by this reduction in the wall thickness so
that this results in, overall, a higher overall efficiency of the
turbine 10.
* * * * *