U.S. patent application number 13/858408 was filed with the patent office on 2013-10-17 for moving blade and turbomachine.
The applicant listed for this patent is MTU AERO ENGINES GMBH. Invention is credited to Alexander Boeck.
Application Number | 20130272880 13/858408 |
Document ID | / |
Family ID | 48082873 |
Filed Date | 2013-10-17 |
United States Patent
Application |
20130272880 |
Kind Code |
A1 |
Boeck; Alexander |
October 17, 2013 |
MOVING BLADE AND TURBOMACHINE
Abstract
A moving blade for a turbomachine, in particular an aircraft
engine, is disclosed, having an inner shroud which has a front
elongation for forming an axial overlap with an upstream guide
blade, and on which at least one flow guide element for deflecting
a leakage flow of a cooling air flow in the peripheral direction is
situated. The at least one flow guide element is guided beyond a
leading edge of the elongation. A turbomachine having a plurality
of these types of moving blades is also disclosed.
Inventors: |
Boeck; Alexander;
(Kottgeisering, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MTU AERO ENGINES GMBH |
Muenchen |
|
DE |
|
|
Family ID: |
48082873 |
Appl. No.: |
13/858408 |
Filed: |
April 8, 2013 |
Current U.S.
Class: |
416/95 |
Current CPC
Class: |
F01D 5/141 20130101;
F05D 2240/80 20130101; F01D 11/001 20130101 |
Class at
Publication: |
416/95 |
International
Class: |
F01D 5/14 20060101
F01D005/14 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 13, 2012 |
DE |
102012206126.6 |
Claims
1. A moving blade for a turbomachine comprising: an inner shroud
having a front elongation for forming an axial overlap with an
upstream guide blade; at least one flow guide element for
deflecting a leakage flow of a cooling air flow being situated in a
peripheral direction, the at least one flow guide element extending
in an axial direction beyond a leading edge of the elongation.
2. The moving blade as recited in claim 1 wherein the flow guide
element terminates in flush alignment with a hot gas side and with
a cooling air side of the elongation.
3. The moving blade as recited in claim 1 wherein the flow guide
element protrudes beyond a hot gas side and a cooling air side of
the elongation in the radial direction.
4. The moving blade as recited in claim 1 wherein the flow guide
element has a hot gas side section on a hot gas side of the
elongation.
5. The moving blade as recited in claim 4 wherein the hot gas side
is located over an entirety of an axial extension of the
elongation.
6. The moving blade as recited in claim 4 wherein the hot gas side
section has a constant height.
7. The moving blade as recited in claim 1 wherein the flow guide
element has a cooling air side section on a cooling air side of the
elongation.
8. The moving blade as recited in claim 7 wherein the cooling gas
side is located over an entirety of an axial extension of the
elongation.
9. The moving blade as recited in claim 7 wherein the cooling gas
side section has a constant height.
10. The moving blade as recited in claim 1 wherein the flow guide
element has a hot gas side section on the hot gas side of the
elongation, and a cooling air side section on a cooling air side of
the elongation.
11. The moving blade as recited in claim 6 the hot gas side section
and the cooling air side section are oriented oppositely with
respect to one another, viewed in a direction of rotation.
12. The moving blade as recited in claim 10 wherein the hot gas
side and/or the cooling air section is located over an entirety of
an axial extension of the elongation.
13. The moving blade as recited in claim 10 wherein the hot gas
side section and/or the cooling air side section has a constant
height.
14. The moving blade as recited in claim 1 wherein the at least one
flow guide element includes a plurality of flow guide elements.
11. A turbomachine comprising: a moving blade row having a
plurality of moving blades as recited in claim 1.
12. An aircraft engine comprising the turbomachine as recited in
claim 11.
Description
[0001] This claims the benefit of German Patent Application DE 10
2012 206 126.6, filed Apr. 13, 2012 and hereby incorporated by
reference herein.
[0002] The present invention relates to a moving blade for a
turbomachine and a turbomachine.
BACKGROUND
[0003] In engine construction it is generally known that the
turbine efficiency may be increased when a leakage flow of a
cooling air flow which is branched off on the compressor side, for
example, is introduced into a hot gas flow between the guide blades
and the moving blades. This type of introduction is described in
U.S. Pat. No. 7,244,104 B2, for example, which is hereby
incorporated by reference herein. In the patent it is proposed to
provide a plurality of flow guide elements in the form of ribs or
indentations on an upstream or front elongation of a moving blade
inner shroud for forming an axial overlap with an upstream guide
blade. The flow guide elements are situated on the elongation on
the hot gas side, and have a front curved section and a rear axial
section on the hot gas side. The curved sections, which extend away
from a leading edge of the elongation in an axial direction and
merge into the axial sections, are oriented in the direction of
rotation. The aim is for the flow guide elements to "blade," in a
manner of speaking, the leakage flow from a root-side cavity in the
guide blades into the hot gas flow, and to impart a peripheral
speed to the leakage flow corresponding approximately to the
peripheral speed of the inner shroud. However, a basic problem in
this regard is how the peripheral speed may be imparted to the
leakage flow without resulting in a hot gas intake into the cavity
on the root side, which could result in overheating of the guide
blades and moving blades in the root area.
SUMMARY OF THE INVENTION
[0004] It is an object of the present invention to provide a moving
blade which allows an optimized introduction of a leakage flow into
a hot gas flow and effectively prevents a hot gas intake, as well
as a turbomachine having improved efficiency.
[0005] The present invention provides a moving blade for a
turbomachine, in particular an aircraft engine, has an inner shroud
having a front elongation for forming an axial overlap with an
upstream guide blade, on which at least one flow guide element for
deflecting a leakage flow of a cooling air flow in the peripheral
direction is situated. According to the present invention, the at
least one flow guide element is guided in the axial direction
beyond a leading edge of the elongation.
[0006] As a result of the at least one flow guide element being
guided in the axial direction beyond the leading edge, a speed is
imparted early to the leakage flow in the peripheral direction, and
thus in the direction of rotation of the moving blade. The leakage
flow is introduced with a swirl into a hot gas flow, thus improving
the introduction of the leakage flow. Hot gas intake from the hot
gas flow in the direction of the cooling air flow is effectively
prevented. The at least one flow guide element is preferably
integrally formed together with the elongation. The at least one
flow guide element may have a linear, curved, wave-like, or other
shape. It must be ensured that the flow guide element does not run
against an axially opposite guide blade section due to thermal
expansion, so that it may be necessary to enlarge an axial distance
between the leading edge and the axially opposite guide blade
section.
[0007] In one exemplary embodiment, the at least one flow guide
element is in flush alignment with a hot gas side and with a
cooling air side of the elongation. The at least one flow guide
element is thus designed as an axial finger, in a manner of
speaking. When there is a plurality of flow guide elements spaced
circumferentially or peripherally apart, the leading edge has a
comb-like shape. The finger-like design has the advantage that, due
to the at least one flow guide element, the elongation does not
become thicker in the radial direction, but, rather, has a radial
extension which has the original thickness or height of the
elongation. Thus, an existing radial plate gap is not diminished by
the at least one flow guide element, and therefore also does not
have to be reset.
[0008] In one alternative exemplary embodiment, the flow guide
element protrudes beyond the hot gas side and beyond the cooling
air side in the radial direction. The at least one flow guide
element therefore has a paddle-like shape. Compared to the
previously mentioned finger-shaped exemplary embodiment, this
exemplary embodiment has the advantage that an effective area of
the flow guide element is enlarged. However, for implementing this
paddle-like flow element, structural changes for radial gap
maintenance may be necessary to prevent the at least one flow guide
element from running against adjacent radial guide blade sections
or components in the radial direction due to thermal expansion.
[0009] In another exemplary embodiment, the at least one flow guide
element has a hot gas side section which is guided on the hot gas
side. The flow guide element is thus elongated on the hot gas side
in a direction away from the leading edge. The aerodynamic action
of the flow guide element may be further intensified in this way.
Depending on the angular setting of the section on the hot gas side
in the axial direction, the leakage flow may be accelerated to a
speed in the peripheral direction which is greater than the
peripheral speed of the inner shroud, thus ensuring that a speed
that is less than or significantly less than the peripheral speed
is not imparted to the leakage flow. At the same time, the
extension of the at least one flow guide element on the elongation
brings about a structural/mechanical stabilization of the
elongation, so that the elongation has a reduced cross section, at
least in the area of the flow guide element, and therefore may be
designed in a weight-optimized manner. Thus, in this exemplary
embodiment the at least one flow guide element also acts as a
reinforcing structure in the form of a rib. Since the at least one
rib-like flow guide element radially outwardly thickens the
elongation at least in sections, for radial gap maintenance,
structural changes may be necessary which compensate for the
diminished original radial distance. For example, for radial gap
maintenance it may be necessary to radially inwardly offset the
elongation.
[0010] In another exemplary embodiment, the at least one flow guide
element has a cooling air side section which is guided on the
cooling air side. In this way, a swirl is already imparted to the
leakage flow in the area of the cooling air side. For accelerating
the leakage flow to a speed in the peripheral direction which is
greater than the peripheral speed of the inner shroud, the at least
one rib-like flow guide element on the cooling air side opposite
from the above-mentioned rib-like flow guide element on the hot gas
side should be angularly set in the axial direction. Since the at
least one rib-like flow guide element radially inwardly thickens
the elongation at least in sections, structural changes may be
necessary for radial gap maintenance.
[0011] In one exemplary embodiment, the at least one flow guide
element has a section on the hot gas side and a section on the
cooling air side. This type of U-shaped flow guide element has the
advantage that the leakage flow is influenced by the at least one
flow guide element on the cooling air side, the leading edge side,
and the hot gas side.
[0012] The section on the hot gas side and the section on the
cooling air side are preferably angularly set oppositely with
respect to one another, viewed in the direction of rotation. As a
result, the leakage flow on the cooling air side and on the hot gas
side is acted on by a velocity component in the same direction. In
particular, the section on the hot gas side is situated in front of
the section on the cooling air side, viewed against the direction
of rotation.
[0013] In particular due to structural-mechanical and production
engineering reasons, it may be advantageous for the section on the
hot gas side and/or the section on the cooling air side to be
guided over the entire length of the elongation. Due to the
stabilizing effect of the at least one flow guide element, it is
thus possible to design the elongation to be thinner, at least in
sections, and thus in a weight-optimized manner, so that the rotor
mass may be reduced.
[0014] From the standpoint of radial gap maintenance, it is
advantageous when the section on the hot gas side and/or the
section on the cooling air side extend(s) in parallel or
essentially in parallel to the respective radially opposite guide
blade section or component. It is therefore preferred that the
section on the hot gas side and/or the section on the cooling air
side has/have a constant height. However, the height of the at
least one flow guide element may also vary. In that case, however,
in order to not adversely affect the separation effect of the plate
gap, it is preferred for the at least one flow guide element to be
flat on the other side of the leading edge.
[0015] The swirl action or aerodynamic effect of the leakage flow
may be additionally influenced by the number of flow guide elements
per elongation. Thus, in one exemplary embodiment, multiple flow
guide elements are situated next to one another on an elongation,
viewed in the peripheral direction.
[0016] A preferred turbomachine has at least one moving blade row
having a plurality of the moving blades according to the present
invention. This type of turbomachine is characterized by an
improved efficiency compared to a turbomachine having conventional
moving blade rows. Significant structural changes to the components
adjacent to this moving blade row, such as guide blade rows and
systems, are not necessary. Depending on the design of the flow
guide elements, only minor structural changes are necessary for gap
maintenance or setting the plate gap.
[0017] Other advantageous exemplary embodiments of the present
invention are the subject matter of further subclaims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Preferred exemplary embodiments of the present invention are
explained in greater detail below with reference to greatly
simplified schematic illustrations.
[0019] FIG. 1 shows a finger-shaped flow guide element, according
to the present invention, of a moving blade;
[0020] FIG. 2 shows a paddle-like flow guide element;
[0021] FIG. 3 shows an example of other exemplary embodiments of
the flow guide element according to the present invention;
[0022] FIG. 4 shows another paddle-like flow guide element;
[0023] FIG. 5 shows a flow guide element having a section on the
hot gas side;
[0024] FIG. 6 shows a flow guide element having a section on the
cooling air side; and
[0025] FIG. 7 shows a flow guide element having a section on the
hot gas side and a section on the cooling air side.
DETAILED DESCRIPTION
[0026] FIG. 1 shows an axial section of a turbomachine 1 in the
area of a guide blade 2 and a downstream moving blade 4. The
turbomachine is preferably an aircraft engine, but may also be a
stationary gas turbine. Guide blade 2 is fastened at the root side
to a housing section or guide blade support ring, and together with
a plurality of further guide blades 2 forms a stationary guide
blade row which surrounds a rotor hub which rotates about a
rotational axis 6. Moving blade 4 is connected at the root side to
the rotor hub via a disk element, for example, and together with a
plurality of further moving blades 4 forms a moving blade row which
rotates with the rotor hub about rotational axis 6. A direction of
rotation or peripheral direction is indicated by the arrow denoted
by reference character u.
[0027] Guide blade 2 has a platform 8 which extends from a blade
tip 10 and represents a radial inner delimitation of a hot gas
path. A hot gas flow 12 flows axially through the hot gas path (in
the x direction). In the exemplary embodiment shown, the hot gas
flow flows through turbomachine 1 from left to right. In order to
stabilize platform 8, the platform has a plurality of webs 14
situated on a side facing away from blade tip 10. However, if
platform 8 has sufficient inherent stability, the webs may be
dispensed with
[0028] A radially inwardly directed fastening flange 16 for
fastening guide blade 2 to a stationary connecting ring surrounding
the rotor hub extends from platform 8. Fastening flange 16 is
situated at a distance from a trailing edge 18 of platform 8, and
together with platform 8 delimits an annular space 20. A peripheral
plate 22 is connected to fastening flange 16, and delimits annular
space 20 in the direction of the rotor hub, thus dividing annular
space 20 into a radially outer cavity and a radially inner
cavity.
[0029] Moving blade 4 has an inner shroud 24 which is situated
between a blade neck 26 or blade shank and a blade 28, and which
represents an inner radial delimitation of the hot gas path. In the
exemplary embodiment shown, the inner shroud is situated
approximately at the same radial position as platform 8. Moving
blade 4 and guide blade 2 are situated with respect to one another
in the axial direction in such a way that between trailing edge 18
of platform 8 and an outer end face 30 of inner shroud 24 an
annular gap 32 is formed, through which a gas exchange between hot
gas flow 12 and a hub-side cooling air flow may take place in
principle. For practically complete structural sealing of annular
gap 32 in the radial direction (y direction), inner shroud 24 has a
front elongation 34 for forming an axial overlap with guide blade 2
or with its platform 8. Elongation 34 extends from outer end face
30 in the direction of guide blade 2, and has a length such that it
protrudes into annular space 20, i.e., the outer cavity between
platform 8 and peripheral plate 22.
[0030] To avoid a hot gas intake, a leakage flow 36 of the cooling
air flow is blown through annular gap 32 into hot gas flow 12.
According to the present invention, at least one flow guide element
38 is provided for introducing leakage flow 36 with a swirl into
hot gas flow 12 or for imparting the peripheral speed of inner
shroud 24 to leakage flow 36. At the same time, the machine
efficiency is improved by the introduction of leakage flow 36,
imparted with swirl, into the hot gas flow.
[0031] In the first exemplary embodiment shown in FIG. 1, flow
guide element 38 is designed as a finger-shaped projection which
extends essentially in the axial direction from a leading edge 40
of front elongation 34. The projection, i.e., flow guide element
38, is preferably linear, but may also be concave, for example in
peripheral direction u. For a plurality of these types of
finger-shaped projections 38, leading edge 40 has a comb-like
shape. Flow guide element 38 preferably merges with flush alignment
into a hot gas side 42 and into a cooling air side 44 of front
elongation 34. In this exemplary embodiment, the projection thus
has the same radial extension as front elongation 34, so that flow
guide element 38 does not act on a radial plate gap between
elongation 34 and web 14 or between elongation 34 and peripheral
plate 22. Depending on the axial extension of the at least one flow
guide element 38 beyond leading edge 40, for the axial gap
maintenance an original axial distance between leading edge 40 and
the fastening flange must be increased.
[0032] In one exemplary embodiment shown in FIG. 2, flow guide
element 38 is designed as a projection on the leading edge side
which is guided beyond hot gas side 42 and beyond cooling air side
44 in the radial direction. Thus, this flow guide element 38 has a
shape that is paddle-like and in particular half moon-like. In
particular, flow guide element 38 has flat outer surfaces. Flow
guide element 38 is preferably not angularly set in axial direction
x and in radial direction y (axial setting angle and radial setting
angle=0.degree.). However, it may also be angularly set in axial
direction x and/or in radial direction y (axial setting angle
and/or radial setting angle.noteq.0.degree.).
[0033] Due to the radial elongation of flow guide element 38 beyond
hot gas side 42 and cooling air side 44, compared to the preceding
finger-shaped exemplary embodiment according to FIG. 1 the at least
one flow guide element 38 according to FIG. 2 has an enlarged
effective area for imparting swirl to leakage flow 36. For radial
gap maintenance or to prevent flow guide element 38 from running
against web 14 and the peripheral plate due to thermal expansion,
it may be necessary to radially inwardly offset elongation 34 and
peripheral plate 22 with respect to the finger-shaped exemplary
embodiment according to FIG. 1. Since the at least one flow guide
element 38 also extends in the direction of peripheral plate 22,
for an axially symmetrical design of flow guide element 38,
peripheral plate 22 must then be radially inwardly offset by twice
the distance compared to elongation 34.
[0034] Further exemplary embodiments of flow guide element 38 are
outlined in FIG. 3. In contrast to the above-mentioned exemplary
embodiments according to FIGS. 1 and 2, these exemplary embodiments
additionally have a rib-like extension in the direction of a blade
neck 26, i.e., a radially outer end face 30, as well as a radially
inner end face 46 of blade neck 26. In this regard, these flow
guide elements 38 have a head section 48 which extends beyond a
leading edge 40 in axial direction x, and a section 50 on the hot
gas side and/or a section 52 on the cooling gas side which
extend(s) from the head section in the direction of blade neck 26.
As indicated by the dashed lines, sections 50, 52 may extend only
over a length of elongation 34, or may merge into end faces 30,
46.
[0035] If sections 50, 52 are guided only over a length of
elongation 34, for structural-mechanical reasons it is preferred
that these sections merge into hot gas side 42 or cooling air side
44 in a stepless, for example ramped, manner. If sections 50, 52
extend to blade neck 26, it is preferred that these sections have a
constant height or extension in the radial direction. Due to
sections 50, 52, the effective area of the at least one flow guide
element 38 is further increased compared to the second exemplary
embodiment according to FIG. 2, which has a positive effect on the
imparting of swirl to leakage flow 36. In addition, in contrast to
the preceding exemplary embodiments according to FIGS. 1 and 2,
flow guide element 38 is stabilized since it surrounds leading edge
40.
[0036] FIG. 4 shows one exemplary embodiment of flow guide element
38 having a section 50 on the hot gas side and a section 52 on the
cooling air side which extend only over a length of an elongation
34. Flow guide element 38 surrounds a leading edge 40 in a U-shaped
manner, and merges continuously into a hot gas side 42 and into a
cooling air side 44. For example, in the side view flow guide
element 38 is a flat circular disk which is interrupted by
elongation 34 in the area of hot gas side 42 and cooling air side
44. Thus, this paddle-like flow guide element 38 has a full-moon
shape, with a head section 48 and two runout sections 50, 52, in a
manner of speaking. Due to the elongation of flow guide element 38
on hot gas side 42 and on cooling air side 44, for the same
extension in the radial direction this exemplary embodiment has a
larger effective area than the exemplary embodiment according to
FIG. 2.
[0037] The at least one flow guide element 38 is preferably not
angularly set in axial direction x and in radial direction y.
However, it may also be angularly set, i.e., positively or
negatively inclined, in axial direction x or in radial direction y.
For radial gap maintenance, elongation 34 and a peripheral plate 22
may be radially inwardly offset, similarly to the exemplary
embodiment according to FIG. 2.
[0038] FIG. 5 shows one exemplary embodiment of a rib-like flow
guide element 38 which extends in axial direction x beyond a
leading edge 40 of an elongation 34, the flow guide element with
its head section 48 terminating in flush alignment with a cooling
air side 44, and with its section 50 on the hot gas side being
guided to outer end face 30. As a result, this flow guide element
38 has an L shape in the side view.
[0039] Section 50 on the hot gas side preferably has an elongated
linear shape with a constant height. This section is angularly set
in axial direction x on a hot gas side 42 of elongation 34. Head
section 48 is preferably not angularly set in axial direction
x.
[0040] In this exemplary embodiment, the inclination of section 50
on the hot gas side is such that, viewed against direction of
rotation u, section 50 on the hot gas side is situated in front of
head section 48. Thus, starting from head section 48, section 50 on
the hot gas side exits the plane of the drawing. Due to the
inclination, upon exiting the outer cavity, leakage flow 36 is
accelerated to a speed u in the peripheral direction which is equal
to or slightly greater than the peripheral speed of inner shroud
24.
[0041] For radial gap maintenance or for preventing flow guide
element 38 from running against web 14 and peripheral plate 22 due
to thermal expansion, elongation 34 and a peripheral plate 22 may,
if necessary, be radially inwardly offset with respect to the
finger-shaped exemplary embodiment according to FIG. 1. Since the
at least one rib-like flow guide element 38 is situated on the
leading edge side and the hot gas side, and therefore an original
radial distance between elongation 34 and peripheral plate 22 is
not diminished, peripheral plate 22 may then be radially inwardly
offset by the same distance as elongation 34.
[0042] FIG. 6 shows one exemplary embodiment of a rib-like flow
guide element 38 which extends in axial direction x beyond a
leading edge 40 of an elongation 34, the flow guide element with
its head section 48 terminating in flush alignment with a hot gas
side 42, and with its section 52 on the cooling air side being
guided to inner end face 46. As a result, this flow guide element
38 likewise has an L shape in the side view.
[0043] Section 52 on the cooling air side preferably has a constant
height and a linear design. This section is angularly set in axial
direction x on a cooling gas side 44 of elongation 34. Head section
48 is preferably not angularly set in axial direction x.
[0044] To accelerate leakage flow 36 to a speed which is
approximately the same as or slightly greater than the peripheral
speed of inner shroud 24, in this exemplary embodiment the
inclination of section 52 on the cooling air side is such that,
viewed against the direction of rotation, section 52 on the cooling
air side is situated behind head section 48. Thus, starting from
head section 48, section 52 on the cooling air side enters the
plane of the drawing.
[0045] For radial gap maintenance, a peripheral plate 22 may, if
necessary, be radially inwardly offset with respect to the
finger-shaped exemplary embodiment according to FIG. 1. Since the
at least one rib-like flow guide element 38 is situated on the
leading edge side and the cooling air side, and therefore an
original radial distance between elongation 34 and web 14 is not
diminished, elongation 34 does not have to be radially inwardly
offset.
[0046] FIG. 7 shows a top view of an unwound peripheral section of
a moving blade row in the area of a front elongation 34 which is
provided with a further exemplary embodiment of flow guide element
38 according to the present invention. According to the
illustration in FIG. 3, flow guide element 38 with its head section
48 surrounds a leading edge 40 of elongation 34 on both sides, and
via a section 50 on the hot gas side and via a section 52 on the
cooling air side is guided to outer and inner end face 30, 46,
respectively. Sections 50, 52 preferably have a uniform constant
height and a linear design. These sections are inclined in axial
direction x, and in particular are oriented with respect to one
another in such a way that that they extend diagonally opposite
from head section 48 in the direction of end faces 30, 46. Head
section 48 is preferably not angularly set in axial direction
x.
[0047] In this exemplary embodiment, the inclination of sections
50, 52 is such that, viewed against direction of rotation u,
section 50 on the hot gas side is situated in front of section 52
on the cooling air side. Thus, starting from head section 48,
section 50 on the hot gas side exits the plane of the drawing, and
starting from head section 48, section 52 on the cooling air side
enters the plane of the drawing. Thus, in the side view this flow
guide element 38 has a rib-like, in particular V-like, shape with
two oppositely pivoted fork sections 50, 52.
[0048] A moving blade for a turbomachine, in particular an aircraft
engine, is disclosed, having an inner shroud which has a front
elongation for forming an axial overlap with an upstream guide
blade, and on which at least one flow guide element for deflecting
a leakage flow of a cooling air flow in the peripheral direction is
situated, the at least one flow guide element being guided beyond a
leading edge of the elongation, and a turbomachine having a
plurality of these types of moving blades.
LIST OF REFERENCE NUMERALS
[0049] 1 turbomachine [0050] 2 guide blade [0051] 4 moving blade
[0052] 6 rotational axis [0053] 8 platform [0054] 10 blade tip
[0055] 12 hot gas flow [0056] 14 web [0057] 16 fastening flange
[0058] 18 trailing edge [0059] 20 annular space [0060] 22
peripheral plate [0061] 24 inner shroud [0062] 26 blade neck [0063]
28 blade [0064] 30 outer end face [0065] 32 annular gap [0066] 34
front elongation [0067] 36 leakage flow [0068] 38 flow guide
element [0069] 40 leading edge [0070] 42 hot gas side [0071] 44
cooling air side [0072] 46 inner end face [0073] 48 head section
[0074] 50 section on the hot gas side [0075] 52 section on the
cooling air side [0076] x axial direction [0077] y radial direction
[0078] u peripheral direction or direction of rotation
* * * * *