U.S. patent application number 14/241172 was filed with the patent office on 2015-01-01 for turbomachine for generating power having a temperature measurement device in a region of the rotor.
This patent application is currently assigned to SIEMENS AKTIENGESELLSCHAFT. The applicant listed for this patent is Guido Ahaus, Ingo Balkowski, Patrick Ronald Flohr, Waldemar Heckel, Harald Hoell, Christian Lyko, Oliver Ricken, Uwe Sieber, Sebastian Stock, Vyacheslav Veitsman, Frank Woditschka. Invention is credited to Guido Ahaus, Ingo Balkowski, Patrick Ronald Flohr, Waldemar Heckel, Harald Hoell, Christian Lyko, Oliver Ricken, Uwe Sieber, Sebastian Stock, Vyacheslav Veitsman, Frank Woditschka.
Application Number | 20150003965 14/241172 |
Document ID | / |
Family ID | 46603976 |
Filed Date | 2015-01-01 |
United States Patent
Application |
20150003965 |
Kind Code |
A1 |
Ahaus; Guido ; et
al. |
January 1, 2015 |
TURBOMACHINE FOR GENERATING POWER HAVING A TEMPERATURE MEASUREMENT
DEVICE IN A REGION OF THE ROTOR
Abstract
A turbomachine having a rotor is provided, wherein the rotor
comprises a central holding element and rotor elements which are
arranged thereon, is intended to permit faster start-up without
reducing the lifetime of the rotor, while permitting better
predictions relating to the remaining lifetime of the rotor. To
this end, a contact element is arranged in a region of the rotor
between the holding element and the rotor element, wherein the
contact element comprises a temperature measurement device.
Inventors: |
Ahaus; Guido; (Essen,
DE) ; Balkowski; Ingo; (Kerken, DE) ; Flohr;
Patrick Ronald; (Mulheim a.d. Ruhr, DE) ; Heckel;
Waldemar; (Essen, DE) ; Hoell; Harald;
(Wachtersbach, DE) ; Lyko; Christian; (Herne,
DE) ; Ricken; Oliver; (Essen, DE) ; Sieber;
Uwe; (Mulheim an der Ruhr, DE) ; Stock;
Sebastian; (Mulheim, DE) ; Veitsman; Vyacheslav;
(Gelsenkirchen, DE) ; Woditschka; Frank;
(Duisburg, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Ahaus; Guido
Balkowski; Ingo
Flohr; Patrick Ronald
Heckel; Waldemar
Hoell; Harald
Lyko; Christian
Ricken; Oliver
Sieber; Uwe
Stock; Sebastian
Veitsman; Vyacheslav
Woditschka; Frank |
Essen
Kerken
Mulheim a.d. Ruhr
Essen
Wachtersbach
Herne
Essen
Mulheim an der Ruhr
Mulheim
Gelsenkirchen
Duisburg |
|
DE
DE
DE
DE
DE
DE
DE
DE
DE
DE
DE |
|
|
Assignee: |
SIEMENS AKTIENGESELLSCHAFT
Munich
DE
|
Family ID: |
46603976 |
Appl. No.: |
14/241172 |
Filed: |
August 2, 2012 |
PCT Filed: |
August 2, 2012 |
PCT NO: |
PCT/EP2012/065098 |
371 Date: |
March 31, 2014 |
Current U.S.
Class: |
415/118 |
Current CPC
Class: |
G01K 1/16 20130101; F01D
17/085 20130101; G01K 13/08 20130101; F01D 5/10 20130101; F01D
25/28 20130101; F01D 21/003 20130101 |
Class at
Publication: |
415/118 |
International
Class: |
F01D 21/00 20060101
F01D021/00; F01D 25/28 20060101 F01D025/28; F01D 5/10 20060101
F01D005/10 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 29, 2011 |
EP |
11179152.1 |
Claims
1. A turbomachine for generating power, comprising: a rotor,
wherein the rotor comprises a central retaining element in the form
of a tie rod and rotor elements in the form of rotor disks arranged
thereon, wherein a contact element is arranged in a region of the
rotor between the central retaining element and the rotor element,
wherein the contact element comprises a temperature measurement
device.
2. The turbomachine as claimed in claim 1, wherein said region of
the rotor is the region which is subjected to the highest thermal
loads in comparison to other regions.
3. The turbomachine as claimed in claim 1, wherein the contact
element is mounted rotatably on an axle, wherein the axle is
attached to the central retaining element.
4. The turbomachine as claimed in claim 1, wherein the contact
element comprises a thermally conductive material on its side
facing the rotor element.
5. The turbomachine as claimed in claim 1, wherein the contact
element comprises an insulating material on its side facing the
central retaining element.
6. The turbomachine as claimed in claim 1, wherein in the region of
a bearing assigned to the central retaining element, the central
retaining element comprises a transmitter connected to the
temperature measurement device on a data side of the device,
wherein said transmitter transmits temperature data.
7. The turbomachine as claimed in claim 1, wherein a plurality of
contact elements is arranged symmetrically about the central
retaining element.
8. The turbomachine as claimed in claim 1, wherein said
turbomachine is configured as a gas turbine.
9. A power plant comprising a turbomachine as claimed in claim 1.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the US National Stage of International
Application No. PCT/EP2012/065098 filed Aug. 2, 2012, and claims
the benefit thereof. The International Application claims the
benefit of European Application No. EP11179152 filed Aug. 29, 2011.
All of the applications are incorporated by reference herein in
their entirety
FIELD OF INVENTION
[0002] The invention relates to a turbomachine having a rotor,
wherein the rotor comprises a central retaining element and rotor
elements arranged thereon.
BACKGROUND OF INVENTION
[0003] A turbomachine is a fluid energy machine in which energy is
transferred between fluid and machine in an open space by means of
a flow according to the laws of fluid dynamics via kinetic energy.
Energy is normally transferred by means of rotor blades which are
shaped such that the flow around them produces a pressure
difference between the front and back sides (wing profile). A
turbomachine typically consists of a rotating part, the rotor, and
a stationary part, the stator.
[0004] A gas turbine is a turbomachine in which a gas under
pressure expands. It consists of a turbine or expander, a
compressor connected upstream thereof, and a combustor connected
between the two. The working principle is based on the cyclic
process (Joule process): this compresses air by means of the
blading of one or more compressor stages, then mixes this air with
a gaseous or liquid fuel in the combustor and ignites and combusts
the mixture. In addition, the air is used for cooling, in
particular of components subjected to high thermal stresses.
[0005] This produces a hot gas (a mixture of combustion gas and
air) which expands in the subsequent turbine part, wherein thermal
energy is converted to mechanical energy and then drives the
compressor. In a shaft engine, the remaining portion is used to
drive a generator, a propeller or other rotating loads. In a jet
engine, by contrast, the thermal energy accelerates the hot gas
stream, producing thrust.
[0006] The rotor of a turbomachine, particularly in the case of gas
turbines, is a component which is subjected to high thermal and
mechanical stresses. It conventionally consists of a central
retaining element, a shaft or axle, to which are attached the
remaining rotating elements such as disks and rotor blades. In
particular in the case of a cold start of the turbomachine, the
rotor disks are in this case subjected to very high stresses. On
one hand, the rotors experience considerable heating in the region
of the blade roots, and on the other hand cooling air flows through
the rotor so that the temperature of the material does not exceed
the strength limits.
[0007] The flow structures and heat transfer effects which appear
inside the rotor are extremely complex and have for decades been
the subject of university research the world over. This applies
first and foremost to the transient processes when starting up or
shutting down the machines.
[0008] In practice, the temperatures occurring in the rotor--and in
particular the temperature gradients which give rise to thermal
stresses--are currently estimated conservatively, i.e. on the safe
side. This often involves FEM (finite element method), a numerical
method for solving partial differential equations, with which
solid-body simulations can be carried out. In this case, the
boundary conditions are determined using individual prototype
measurements. Sample measurements of the temperature of individual
rotor components are also carried out here in part.
[0009] The data obtained in this manner are used, on one hand, to
estimate the maximum number of start cycles that a rotor can
withstand before it has to be replaced and, on the other hand, to
estimate a rotor preheat time, which is necessary in certain cases
in order to reduce thermal stresses to an acceptable level and to
keep the number of permitted start cycles high enough. However,
waiting a certain time before commencement of operation of the
rotor always implies increased energy consumption and a longer
startup time for the turbomachine, which is undesirable,
particularly for example in the case of gas turbine and steam
turbine power plants, as these often have to cover peak power
requirements of the electrical grid at short notice.
SUMMARY OF INVENTION
[0010] It is therefore an object of the invention to indicate a
turbomachine which allows faster startup without this reducing the
lifespan of the rotor, and at the same time allows better
prediction of the remaining lifespan of the rotor.
[0011] This object is achieved, according to the invention, by a
contact element being arranged in a region of the rotor between the
retaining element and the rotor element, wherein the contact
element comprises a temperature measurement device.
[0012] The invention thus proceeds from the consideration that
faster startup and better estimation of the lifespan would be
possible in particular if especially precise and up-to-date data on
the temperature behavior of the rotor of a turbomachine for
generating power were made available. To that end, it is possible,
for example based on the adaptation to transient temperature
profiles from FEM models, to derive analytical temperature formulae
by means of which the material temperature can be estimated on the
basis of measured operational data. An estimation of this kind
must, however, always be conservative with respect to operational
safety and lifespan. This can for example have the consequence
that, during startup, there is an unnecessarily long wait for the
corresponding temperature conditions or even that the process of
starting the turbomachine is locked, even though the required
material temperature has been reached, as the temperature formula
has estimated the temperature as too low.
[0013] For this reason, the temperature must be determined still
more precisely. This can be achieved by directly measuring the
temperature in that region of the rotor which is of interest. This
is however problematic in that certain regions of the rotor, in
particular the disk hubs subjected to particularly high thermal
stresses, are arranged inside the turbomachine and access to these
is therefore difficult. Hence, a means should be found to measure
the material temperature using an appropriate arrangement of a
temperature measurement device. This can be achieved by the
temperature measurement device being arranged in a contact element
between the rotor element to be measured and the retaining element
of the rotor. This can be effected with the aid of temperature
converters such as resistance sensors or thermocouples. The contact
element is then pressed against the retaining element by
centrifugal force during rotation of the rotor, thus ensuring good
contact and good heat transfer.
[0014] In this case the central rotor element is a tie rod and/or
the rotor element is a rotor disk, i.e. the contact element is
located between the tie rod and the rotor disks attached thereto.
Contact elements can thus be attached to all disks over the entire
axial length and the temperature of these can thus be detected. At
the same time, this means that the rotor of a stationary
turbomachine designed for industrial power generation is
particularly stable and of simple construction.
[0015] Advantageously, said region of the rotor is the region which
is subjected to the highest thermal loads in comparison to other
regions. Indeed, not all regions of the rotor of the turbomachine
are subjected to the same level of load in operation. Thus, for
example, the disk hubs of the rotor are comparatively highly loaded
parts. In order that a temperature measurement does not need to be
carried out in all regions, it should be ensured that in every case
the highly loaded regions which are critical for calculating the
lifespan are precisely measured.
[0016] Thus, determining the lifespan of the rotor is improved
while reducing expenditure.
[0017] In a further advantageous configuration, the contact element
is mounted rotatably on an axle, wherein the axle is attached to
the central retaining element. This means that the contact element
is configured as a pawl which is attached to the central retaining
element, in particular the tie rod. By virtue of the rotatably
mounted axle, this pawl moves, under the effect of centrifugal
force, outward on the side facing away from the axle and wedges the
surrounding rotor component, in particular the rotor disk. The pawl
thus serves two purposes: on one hand to attach and centrally and
symmetrically secure the rotor disk, and on the other hand in the
chain of transmitting the signal of the disk temperature to the
pawl temperature, data transmission and monitoring. The pawls may
also be used to damp oscillations in the rotor. An advantageous
embodiment of the pawl is in this case such that even at turning
rotational speed, i.e. when the turbomachine is started up, it
bears against the disk with sufficient force and such that at
operating speed it allows a relative expansion of the rotor
components.
[0018] The contact element advantageously comprises a thermally
conductive material on its side facing the rotor element. This
ensures a particularly good transfer of heat from the region to be
measured on the rotor disk to the temperature measurement device,
which improves the quality of the temperature determination.
[0019] In a further advantageous configuration, the contact element
comprises an insulating material on its side facing the central
retaining element. This prevents an input of heat or a loss of heat
in the direction of the central tie rod. This also improves the
quality of the temperature determination.
[0020] The central retaining element advantageously comprises, in
the region of a bearing assigned to it, a transmitter connected to
the temperature measurement device on the data side and serving to
transmit the temperature data. The data line from the temperature
measurement device thus runs on or in the central retaining
element, e.g. the tie rod to the bearing, which is typically
arranged in an outer region. The transmitter can for example be
designed according to the inductive principle or by means of
sliding contacts and thus allows signals to be transmitted to the
stationary components. An embodiment of this type can be
operationally active for long periods of operation. For reasons of
good accessibility, positioning the transmitter on a bearing also
makes it possible to carry out maintenance without dismantling the
rotor.
[0021] In an advantageous configuration, a plurality of contact
elements is arranged symmetrically about the central retaining
element. This avoids imbalances and allows temperature measurement
over the entire circumference.
[0022] The turbomachine is advantageously a gas turbine.
Specifically in gas turbines, whose components, in particular the
rotor, are subjected to the highest thermal and mechanical
stresses, the described configuration is of considerable advantage
with respect to determining lifespan and reduces the startup time
without sacrificing operational safety or lifespan.
[0023] A turbomachine of this type is advantageously used in a
power plant.
[0024] The advantages achieved with the invention are in particular
that, by virtue of measuring over the entire lifespan of the
turbomachine, up-to-date data on the temperature behavior of the
rotor are available. With the aid of these data, substantially more
precise lifespan estimates for rotors can be made, and the number
of permissible starts, corresponding to physical actualities, can
be adapted in an up-to-date manner. This is an immediate industrial
advantage for the operator, in particular in the case of
installations with frequent cold starts. At the same time,
continuous temperature measurement permits a better estimation of
the rotor lifespan and a shortening of the startup process without
reducing the lifespan. In addition to the time saving and thus
increased flexibility, less energy is also used for startup. Direct
temperature measurement, together with the signal line in the
region of the bearings, further presents a particularly
maintenance-friendly system for continuous temperature
measurement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The invention is described in more detail with reference to
a drawing, in which:
[0026] FIG. 1 shows an axial section through a gas turbine,
[0027] FIG. 2 shows an axial section through a partial region of
the rotor of the gas turbine of FIG. 1, and
[0028] FIG. 3 shows a radial section through a contact element of
the gas turbine.
DETAILED DESCRIPTION OF INVENTION
[0029] In all figures, identical parts are given the same reference
signs.
[0030] A gas turbine 101 as shown in FIG. 1 is a turbomachine. It
has a compressor 102 for combustion air, a combustor 104 and a
turbine unit 106 for driving the compressor 102 and a generator
(not shown) or a work machine. To that end, the turbine unit 106
and the compressor 102 are arranged on a common turbine shaft 108,
also termed the turbine rotor, to which the generator or, as the
case may be, the work machine is also connected, and which is
mounted rotatably about its central axis 109. These units form the
rotor of the gas turbine 101. The combustor 104, which is embodied
as an annular combustor, is equipped with a number of burners 110
for burning a liquid or gaseous fuel.
[0031] The turbine unit 106 has a number of rotary rotor blades 112
which are connected to the turbine shaft 108. The rotor blades 112
are arranged in a ring shape on the turbine shaft 108 and thus form
a number of rotor blade rings or rows. The turbine unit 106 further
comprises a number of stationary guide vanes 114 which are
attached, also in a ring shape, to a guide vane carrier 116 of the
turbine unit 106 so as to form guide vane rows. The rotor blades
112 serve in this context to drive the turbine shaft 108 by impulse
transfer from the working medium M which flows through the turbine
unit 106. The guide vanes 114 serve, on the other hand, to guide
the flow of the working medium M between in each case two
successive--as seen in the direction of flow of the working medium
M--rotor blade rows or rotor blade rings. A successive pair, having
a ring of guide vanes 114 or a guide vane row and of a ring of
rotor blades 112 or a rotor blade row, is in this context also
termed a turbine stage.
[0032] Each guide vane 114 has a platform 118 which is arranged as
a wall element for fixing the respective guide vane 114 to a guide
vane carrier 116 of the turbine unit 106. The platform 118 is in
this context a component which is subjected to comparatively high
thermal loads and which forms the outer limit of a hot gas channel
for the working medium M which flows through the turbine unit 106.
Each rotor blade 112 is, in analogous fashion, attached to the
turbine shaft 108 by means of a platform 119, also termed the blade
root.
[0033] A ring segment 121 is in each case arranged on a guide vane
carrier 116 of the turbine unit 106 between the spaced apart
platforms 118 of the guide vanes 114 of two adjacent guide vane
rows. The outer surface of each ring segment 121 is in this context
also exposed to the hot working medium M flowing through the
turbine unit 106, and is separated in the radial direction from the
outer end of the rotor blades 112 located opposite by a gap. The
ring segments 121 arranged between adjacent guide vane rows serve
in this context in particular as covering elements which protect
the interior housing in the guide vane carrier 116, or other
integrated housing parts, from thermal overloading caused by the
hot working medium M which is flowing through the turbine 106.
[0034] In an exemplary embodiment, the combustor 104 is configured
as what is termed an annular combustor, wherein a multiplicity of
burners 110, arranged around the turbine shaft 108 in the
circumferential direction, open into a common combustor space. To
that end, the combustor 104 is configured in its entirety as an
annular structure which is positioned around the turbine shaft
108.
[0035] In order to permit a better prediction of the lifespan of
the rotor and the requisite possible preheat times, the gas turbine
101 is configured for a temperature measurement in the rotor. This
is shown in FIG. 2, which represents an enlarged section through
the rotor of the gas turbine 101.
[0036] This shows the more detailed construction of the rotor in
axial section: the already-described rotor blades 112 of the
turbine unit 106 are in each case attached, together with the
platforms 119, to one rotor disk 122 per rotor blade row. The rotor
disks 122 are attached to a tie rod 124. A pawl 126, which is
rotatably attached to an axle 128 by means of nuts 130, is arranged
in the region subjected to the greatest thermal load. A data line
132 leads to a temperature measurement device 134 in the pawl
126.
[0037] FIG. 3 shows a radial section through the rotor, wherein the
shape of the pawl 126 can be seen. The temperature measurement
device 134 is arranged in the region facing the rotor disk 122. A
material with good thermal conductivity is applied on top of it and
an insulator underneath it. The data line 132 leads from the
temperature measurement device 134 to a bearing (not shown) of the
rotor, where it leads into a transmitter which transmits the
temperature data to stationary components.
[0038] When the tie rod 124 rotates with the rotor, the pawl 126 is
pressed against the rotor disk 122 such that there exists a good
transfer of heat to the temperature measurement device 134. The
pawl 126 thus fulfills multiple functions: on one hand it secures
the rotor disk and provides radial equalization, on the other hand
it serves as a transmission member in the temperature measurement.
In addition, the pawl 126 serves to damp oscillations.
[0039] By means of the temperature measurement, the startup time of
the gas turbine 101 is on one hand reduced. On the other hand,
temperature data for the rotor are available, which permits
particularly precise predictions with respect to the lifespan of
the gas turbine 101.
* * * * *