U.S. patent application number 14/126437 was filed with the patent office on 2014-05-15 for gas turbine with pyrometer.
This patent application is currently assigned to SIEMENS AKTIENGESELLSCHAFT. The applicant listed for this patent is Thomas Bosselmann, Michael Willsch. Invention is credited to Thomas Bosselmann, Michael Willsch.
Application Number | 20140133994 14/126437 |
Document ID | / |
Family ID | 46210236 |
Filed Date | 2014-05-15 |
United States Patent
Application |
20140133994 |
Kind Code |
A1 |
Bosselmann; Thomas ; et
al. |
May 15, 2014 |
GAS TURBINE WITH PYROMETER
Abstract
A gas turbine with at least one stationary stator blade and at
least one rotor blade that can be rotated during operation is
provided. The gas turbine has at least one optical waveguide
embedded into a first rotor blade. The optical waveguide is
oriented such that thermal radiation of a region of the first
stator blade can be detected by the optical waveguide. An analyzing
device is designed to analyze the thermal radiation and to
ascertain the temperature of the region of the first stator blade,
the temperature being ascertainable along a path from which the
radiation is emitted during the rotation of the first rotor
blade.
Inventors: |
Bosselmann; Thomas;
(Marloffstein, DE) ; Willsch; Michael; (Jena,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Bosselmann; Thomas
Willsch; Michael |
Marloffstein
Jena |
|
DE
DE |
|
|
Assignee: |
SIEMENS AKTIENGESELLSCHAFT
Munich
DE
|
Family ID: |
46210236 |
Appl. No.: |
14/126437 |
Filed: |
May 31, 2012 |
PCT Filed: |
May 31, 2012 |
PCT NO: |
PCT/EP2012/060209 |
371 Date: |
December 15, 2013 |
Current U.S.
Class: |
416/223R |
Current CPC
Class: |
F05D 2260/80 20130101;
F01D 5/14 20130101; F01D 21/003 20130101; G01J 5/0821 20130101;
F01D 17/085 20130101; G01J 5/0088 20130101 |
Class at
Publication: |
416/223.R |
International
Class: |
F01D 5/14 20060101
F01D005/14 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 21, 2011 |
DE |
102011077908.6 |
Claims
1. A gas turbine, comprising at least one stationary stator blade
and at least one rotor blade which can be rotated during operation,
at least one optical waveguide, which is embedded in a first rotor
blade and is aligned such that thermal radiation of a region of the
first stator blade can be detected by the optical waveguide, and an
evaluation device for evaluating the thermal radiation, which is
configured to determine the temperature of the region of the first
stator blade, it being possible to determine the temperature along
a path from which the thermal radiation emanates in the course of
the rotation of the first rotor blade.
2. The gas turbine as claimed in claim 1, wherein the first rotor
blade comprises a photodetector for converting the thermal
radiation into electrical signals.
3. The gas turbine as claimed in claim 2, wherein the photodetector
is fed by wireless energy transfer.
4. The gas turbine as claimed in claim 1, wherein the optical
waveguide is guided into the shaft of the first rotor blade and
terminates there.
5. The gas turbine as claimed in claim 4, wherein the end of the
optical waveguide in the shaft is provided with a collimator.
6. The gas turbine as claimed in claim 5, wherein the collimator is
configured to emit the emerging radiation in an axial parallel
beam.
7. The gas turbine as claimed in claim 4, wherein the radiation
coming from the collimator is detected with the aid of a detection
device, wherein the reception range of the detection device is
formed over so large an area that substantially all radiation
coming from the collimator can be detected.
8. The gas turbine as claimed in claim 7, wherein the detection
device has a cover or sleeve to prevent ambient light from
scattering in.
9. The gas turbine as claimed in claim 7, wherein the detection
device is an optical waveguide or a bundle of optical waveguides
for passing on the radiation to a photodetector.
10. The gas turbine as claimed in claim 7, wherein the detection
device is a photodetector.
11. The gas turbine as claimed in claim 1, wherein a lens
collimator is provided in the region of the end of the optical
waveguide pointing toward the first stator blade.
12. The gas turbine as claimed in claim 1, wherein the optical
waveguide is tapered at its end.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the U.S. National Stage of International
Application No. PCT/EP2012/060209 filed May 31, 2012, and claims
the benefit thereof. The International Application claims the
benefit of German Application No. DE 102011077908.6 filed Jun. 21,
2011. All of the applications are incorporated by reference herein
in their entirety.
FIELD OF INVENTION
[0002] The invention relates to a gas turbine having at least one
stationary stator blade and at least one rotor blade which can be
rotated during operation.
BACKGROUND OF INVENTION
[0003] Work on the efficiency of modern gas turbines never stops.
An increased efficiency can always be achieved in this case by an
increased operating temperature. Here, the operating temperature
continuously approaches the limits of the thermostability of the
blade materials being used. In order to avoid overloading, the
temperature of individual components of a gas turbine is monitored.
By way of example, pyrometers are used for this purpose which
detect the thermal radiation of individual components, lead it to a
detector and evaluate it there, thus determining the temperature of
the component. A multiplicity of temperature measurement points and
temperature measuring devices are used so as to be able to measure
local variations in the temperature.
[0004] Owing to their fixed position relative to the burners, the
stationary blades, called stator blades, have larger
inhomogeneities in the temperature distribution than the rotor
blades, which rotate during operation. The temperature distribution
in the stator blades is therefore of great interest. To date, the
temperature of the stator blades has been measured in a punctiform
manner with the aid of a limited number of stationary
thermoelements.
SUMMARY OF INVENTION
[0005] It is an object of the present invention to specify a gas
turbine in the case of which the temperature distribution in the
stator blades can be more accurately detected.
[0006] This object is achieved by a gas turbine as described
herein.
[0007] The gas turbine according to an embodiment comprises at
least one stationary stator blade and at least one rotor blade
which can be rotated during operation. Also present is at least one
optical waveguide, which is embedded in a first rotor blade and is
aligned such that thermal radiation of a first stator blade can be
detected by the optical waveguide.
[0008] The gas turbine according to an embodiment also comprises an
evaluation device for evaluating thermal radiation. The evaluation
device is configured to determine the temperature of at least the
first stator blade, it being possible to determine the temperature
along a path from which the thermal radiation is detected in the
course of the rotation of the first rotor blade and thus of the
optical waveguide.
[0009] The region of the stator blade whose thermal radiation is
recorded is in this case a function of the optical waveguide and of
the distance of the optical waveguide end from the stator
blade.
[0010] Differently put, in an embodiment the pyrometer, which is
represented by the optical waveguide, rotates together with a rotor
blade and is directed toward a stator blade. The temperature of the
stator blade can therefore advantageously no longer be determined
only at fixed points at which thermal elements are provided, but at
any point on a circular track which results from the movement of
the rotor blade relative to the stator blade. The temperature
distribution of the stator blade can thus be detected much more
accurately than previously.
[0011] In one refinement and development of an embodiment, the
first rotor blade comprises a photodetector for converting the
thermal radiation into electrical signals. In this case, the
photodetector is expediently coupled to the optical waveguide in
order to be able to detect the thermal radiation, which comes from
the first stator blade, after passage through the optical
waveguide. The photodetector can, for example, be fed in this case
by wireless energy transfer. Alternatively, the photodetector can
be fed by means of a battery. The pyrometer is advantageously
implemented thereby substantially in the rotor blade itself. The
data determined can then be recorded and/or passed on by telemetry
or by a corotating data plotter.
[0012] In a further refinement and development of an embodiment,
the optical waveguide is guided into the shaft of the first rotor
blade and terminates there. It is possible through this
configuration for the recorded thermal radiation to be output in
the direction of stationary parts of the gas turbine. Said
radiation can be more simply recorded and further processed there.
It is then advantageous when the end of the optical waveguide in
the shaft is provided with a collimator. In accordance with an
advantageous refinement of an embodiment, it is possible hereby for
the emerging thermal radiation to be emitted in an axial parallel
beam. This enables the radiation to be recorded as far as possible
without attenuation after traversing a short air gap.
[0013] In an advantageous refinement of an embodiment, the
radiation coming from the collimator is detected with the aid of a
detection device, wherein the reception range of the detection
device is formed over so large an area that substantially all
radiation coming from the collimator can be detected. The
comparatively large area of the configuration of the detection
device enables the thermal radiation to be detected and further
processed without attenuation. The accuracy of the measurement is
thereby ensured.
[0014] In order to separate the detection device from the ambient
light, and thus to reduce or to avoid a recording of the ambient
light, it is advantageous to provide a cover or sleeve in the
region of the detection device.
[0015] In one refinement of an embodiment, the detection device is
an optical waveguide, in particular an optical waveguide with a
comparatively large cross section, or a bundle of optical
waveguides. The optical waveguide/waveguides serves/serve to pass
on radiation in a stationary part of the gas turbine to a
photodetector. The use of optical waveguides as detection device
enables the detector to be implemented in a thermally less stressed
region of the gas turbine.
[0016] Alternatively, the detection device can also directly be the
photodetector. Said photodetector is then preferably provided with
a sufficiently large detector area in order, in turn, to provide as
far as possible for attenuation-free recording of the thermal
radiation.
[0017] In one advantageous refinement and development of an
embodiment, a lens collimator is provided in the region of the end
of the optical waveguide reaching the first stator blade.
Alternatively, the optical waveguide can be configured in a tapered
fashion at its appropriate end. It is thereby possible to control
the region of the surface of the stator blade from which thermal
radiation is recorded.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Preferred, but in no way limiting exemplary embodiments of
the invention are now explained in more detail with the aid of the
figures of the drawing, in which the features are schematized. In
the drawing:
[0019] FIG. 1 shows an arrangement of the rotating pyrometer in
principle, and
[0020] FIG. 2 shows variants of the receiving collimator on the
rotor blade.
DETAILED DESCRIPTION OF INVENTION
[0021] FIG. 1 shows a section of a gas turbine 10. This means that
only parts of the components are schematized. The gas turbine 10
comprises a rotor blade 11 and stator blades 12. The rotor blade 11
is arranged rotatably on a shaft 17. The stator blades 12 are
arranged fixed to the housing and do not rotate during
operation.
[0022] A glass fiber 13 is embedded in the rotor blade 11. It runs
therein from an end situated on the surface of the rotor blade 11
into the shaft 17. The end situated on the surface of the rotor
blade 11 points in the direction of the stator blades 12. Provided
at the end of the optical waveguide 13 there is a lens collimator
14.
[0023] The other end of the glass fiber 13 lies on a surface of the
shaft 17. The glass fiber 13 terminates there with a second
collimator 18. The second collimator 18 is configured in this case
such that the output radiation emerges in an axial parallel beam.
The radiation thus output enters a photodetector 20 whose receiving
surface has a large area by comparison with the cross section of
the glass fiber 13.
[0024] FIG. 2 shows variants of the termination of the glass fiber
13, which points in the direction of the stator blades 12. Thus, as
indicated in this exemplary embodiment, the glass fiber 13 can be
terminated with the lens collimator 14. A further possibility and
alternative consists in terminating the glass fiber 13 in such a
way that the glass fiber has a tapered end 22. A further
alternative consists in using a glass fiber 13 of lower aperture.
Said end 21 of the glass fiber 13 then has no special
configuration.
[0025] During operational running, a region 16 of a stator blade 12
emits thermal radiation in accordance with its temperature. In this
case, the region 16 is small by comparison with the size of the
stator blade 12. The thermal radiation enters the glass fiber 13
via the lens collimator 14. It is led there up to its other end and
enters the photodetector 20 through the second collimator 18 and
the following air gap. The electrical signals initiated by the
radiation 19 are evaluated, and the temperature of the region 16 is
thereby determined.
[0026] The rotor blade 11 rotates during operational running. The
glass fiber 13 necessarily co-rotates in this case. The region 16
of the stator blade 12 that is under consideration thereby travels
around the shaft 17 on a circular track. Since said movement is
relatively quick, it is possible at practically any time to
consider the temperature of each region 16 of the stator blade 12
which lies on the circular track. All that this requires is to wait
until the rotor blade 11 has passed once over the desired region
16. The temporal resolution of the evaluation in this case
determines which angular section of the circular path will
ultimately be regarded as region 16.
* * * * *