EP1182399A2 - Verfahren zur Reduzierung thermoakustischer Schwingungen in Strömungskraftmaschinen mit einem Brennsystem - Google Patents
Verfahren zur Reduzierung thermoakustischer Schwingungen in Strömungskraftmaschinen mit einem Brennsystem Download PDFInfo
- Publication number
- EP1182399A2 EP1182399A2 EP01116012A EP01116012A EP1182399A2 EP 1182399 A2 EP1182399 A2 EP 1182399A2 EP 01116012 A EP01116012 A EP 01116012A EP 01116012 A EP01116012 A EP 01116012A EP 1182399 A2 EP1182399 A2 EP 1182399A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- fuel
- burner
- pulsed
- air mixture
- frequency
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C15/00—Apparatus in which combustion takes place in pulses influenced by acoustic resonance in a gas mass
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C7/00—Combustion apparatus characterised by arrangements for air supply
- F23C7/002—Combustion apparatus characterised by arrangements for air supply the air being submitted to a rotary or spinning motion
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
- F23R3/00—Continuous combustion chambers using liquid or gaseous fuel
- F23R3/28—Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply
- F23R3/286—Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply having fuel-air premixing devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C2205/00—Pulsating combustion
- F23C2205/10—Pulsating combustion with pulsating fuel supply
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN A CARRIER GAS OR AIR
- F23C2900/00—Special features of, or arrangements for combustion apparatus using fluid fuels or solid fuels suspended in air; Combustion processes therefor
- F23C2900/07002—Premix burners with air inlet slots obtained between offset curved wall surfaces, e.g. double cone burners
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
- F23R2900/00—Special features of, or arrangements for continuous combustion chambers; Combustion processes therefor
- F23R2900/00013—Reducing thermo-acoustic vibrations by active means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
- F23R2900/00—Special features of, or arrangements for continuous combustion chambers; Combustion processes therefor
- F23R2900/00014—Reducing thermo-acoustic vibrations by passive means, e.g. by Helmholtz resonators
Definitions
- the invention relates to a method for reducing thermoacoustic Vibrations in a fluid flow machine with a burner system that provides at least one burner into which at least one burner nozzle Fuel is introduced, the combustion air flowing into the burner is mixed into a fuel / air mixture, which in one, to the Burner system subsequent combustion chamber is brought to ignition.
- thermoacoustic vibrations often occur in the combustion chambers, which arise on the burner as fluid-mechanical instability waves and lead to flow vortices that have a strong influence on the entire combustion process and lead to undesired periodic heat releases within the combustion chamber, which are associated with strong pressure fluctuations.
- the high pressure fluctuations are associated with high vibration amplitudes, which can lead to undesirable effects, such as a high mechanical load on the combustion chamber housing, an increased NO x emission due to inhomogeneous combustion and even an extinguishing of the flame within the combustion chamber.
- Thermoacoustic vibrations are based, at least in part, on flow instabilities the burner flow, which is expressed in coherent flow structures, and that affect the mixing processes between air and fuel.
- cooling air is in the form of a cooling air film over the Headed combustion chamber walls.
- the cooling air film also works sound absorbing and helps to reduce thermoacoustic vibrations at.
- the Cooling air flow into the combustion chamber is significantly reduced and all of the air is through directed the burner.
- the sound absorbing is also reduced Cooling air film, which reduces the sound-absorbing effect and with the problems associated with the undesirable vibrations are increasing again.
- thermoacoustic vibration amplitudes is associated with the disadvantage that the injection of fuel at the head stage is accompanied by an increase in the emission of NO x .
- thermoacoustic Vibrations Although the emission values deteriorate only marginally, however, this can be particularly useful in gas turbines due to instabilities which form high due to thermoacoustic vibrations Frequencies in the kHz range are insufficiently countered.
- the invention is based on the object of a method for reducing thermoacoustic Vibrations in a fluid power machine with a burner system, which provides at least one burner, in the at least one burner nozzle Fuel is introduced with the flowing into the burner Combustion air is mixed into a fuel / air mixture that is in a combustion chamber connected to the burner system for ignition will be developed in such a way that high-frequency thermoacoustic vibrations effectively and without the need for costly and maintenance-intensive components can be suppressed.
- the method according to the preamble of claim 1 provides the high-frequency, combustion-driven vibrations or thermoacoustic Vibrations as they are called by a low frequency Suppress excitation of the fuel mass flow.
- the fuel pulsed through the burner nozzle into the burner with variable or fixed Frequencies between 0.1 Hz and 1000 Hz, preferably between 1 and 20 Hz, brought in.
- thermoacoustic instabilities with a considerable high-frequency component due to low-frequency modulation of the fuel mass flow through pulsed fuel injection just the high-frequency Proportion of thermoacoustic vibrations can be effectively suppressed.
- thermoacoustic instabilities are based on the one hand on coherent vortex detachments, which arise, for example, immediately after the burner outlet, and on the other hand on fluctuations in the mixture during the mixing of the fuel with the combustion air in the premixing stage. If one influences the phase position between the fuel injection and the periodic heat release due to one of the excitation mechanisms, the combustion instabilities can be controlled. In particular, it is important to disturb the phase position between the periodic heat release and the fuel injection in such a way that the so-called Rayleigh criterion is no longer met.
- Spq represents the cross spectrum between pressure fluctuations p 'and fluctuations in the heat release q' and ⁇ pq the phase difference.
- the Rayleigh index can be set to G (x) ⁇ 0, which dampens the system.
- the suppression of combustion-driven vibrations is therefore based on that the phases of fuel injection and heat release are not in the Are kind of correlated that the Rayleigh criterion is met.
- Liquid or gaseous fuel passes from a fuel reservoir 1 an injector 2 into the interior of a burner 3 in which the atomized fuel together with combustion air forms a fuel / air mixture that after complete mixing reaches the combustion chamber 4, in which it is ignited and is available for the operation of a gas turbine, for example.
- the injection nozzle 2 can be controlled in such a way that its nozzle opening can be closed, so that depending on the control of the injector 2, a pulsed fuel input in the burner 3 is possible.
- a Frequency generator 5 is provided, whose control signals from an amplification unit 6 amplified and fed to the injector 2.
- Any predefinable frequency values can be set, the pulse frequency of the fuel input into the burner 3. As a rule, you can do this empirically determined frequencies at which effective suppression thermoacoustic instabilities can be observed.
- FIG. 2 shows a diagram based on the effect of the invention Measure for the formation of thermoacoustic vibrations in the kHz range can be seen.
- the diagram shows amplitude values of pressure vibrations along the abscissa and plotted a scale along the ordinate showing the strength of the formation of Reproduces pressure vibrations.
- the entered line with the filled squares represents a major instability in the kHz range.
- a low frequency excitation see the Line with the filled diamonds
- the high-frequency instability could be suppressed by 39 dB. in this connection only the amplitude of the excitation signal is changed, its frequency remains constant in the case shown in FIG. 2.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluidized-Bed Combustion And Resonant Combustion (AREA)
Abstract
Description
Zur Unterdrückung der verbrennungsgetriebenen Schwingungen gilt es insbesondere, die Phasen der Brennstoffeindüsung und der Wärmefreisetzung derart zu korrelieren, daß das Rayleigh-Kriterium nicht erfüllt ist. Es gilt:
- Fig. 1
- Blockdiagramm zur Darstellung einer verwendeten Steuerkette zur Unterdrückung thermoakustischer Schwingungen innerhalb eines Brennersystems und
- Fig. 2
- Diagramm zur Darstellung der Effizienz des erfindungsgemäßen Verfahrens.
- 1
- Brennstoffreservoir
- 2
- Einspritzdüse
- 3
- Brenner
- 4
- Brennkammer
- 5
- Frequenzgenerator
- 6
- Verstärkereinheit
Claims (7)
- Verfahren zur Reduzierung thermoakustischer Schwingungen in einer Strömungskraftmaschinen mit einem Brennersystem, das wenigstens einen Brenner (3) vorsieht, in den über wenigstens eine Brennerdüse (2) Brennstoff eingebracht wird, der mit in den Brenner (3) einströmenden Verbrennungszuluft zu einem Brennstoff/Luftgemisch vermischt wird, das in einer, sich an das Brennersystem anschließenden Brennkammer (4) zur Zündung gebracht wird,
dadurch gekennzeichnet, dass der Brennstoff durch die Brennerdüse (2) in den Brenner (3) gepulst mit variablen oder festen Frequenzen zwischen 1 Hz und 1000 Hz eingebracht wird. - Verfahren nach Anspruch 1,
dadurch gekennzeichnet, dass die gepulste Brennstoffzugabe durch die Brennerdüse (2) derart erfolgt, dass sich die Ausbildung des Brennstoff-/Luftgemisch ebenso gepulst erfolgt. - Verfahren nach Anspruch 1 oder 2,
dadurch gekennzeichnet, dass die gepulste Brennstoffzugabe unabhängig von sich im Brennersystem ausbildenden thermoakustischen Schwingungen, d.h. in einem "open loop", erfolgt. - Verfahren nach Anspruch 1 oder 2,
dadurch gekennzeichnet, dass die gepulste Brennstoffzugabe mit einer Frequenz erfolgt, die etwa bei 1,5 % der Frequenz liegt, mit der sich die thermoakustischen Schwingungen ausbilden. - Verfahren nach einem der Ansprüche 1 bis 4,
dadurch gekennzeichnet, dass das unmittelbar aus dem Brenner (3) ausströmende Brennstoff-/Luftgemisch im Rahmen einer Vormischstufe möglichst vollständig durchmischt wird, bevor das Gemisch in der Brennkammer (4) gezündet wird. - Verfahren nach einem der Ansprüche 1 bis 5,
dadurch gekennzeichnet, dass zur Erzeugung des Brennstoff-/Luftgemisches ein Brenner verwendet wird, der aus mindestens zwei hohlen, in Strömungsrichtung des Brennstoff-/Luftgemisches ineinandergeschachtelten Teilkörpern besteht, deren Mittelachsen zueinander versetzt laufen, dergestalt, dass benachbarte Wandungen der Teilkörper tangentiale Lufteintrittskanäle für die Einströmung von Verbrennungsluft in einen von den Teilkörpem vorgegebenen Innenraum bilden, und wobei der Brenner zumindest eine axial angeordnete Brennstoffdüse, durch die der Brennstoff gepulst eingedüst wird, aufweist. - Verfahren nach einem der Ansprüche 1 bis 6,
dadurch gekennzeichnet, dass als Strömungskraftmaschinen Gasturbinenanlagen verwendet werden.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE10040868A DE10040868A1 (de) | 2000-08-21 | 2000-08-21 | Verfahren zur Reduzierung thermoakustischer Schwingungen in Strömungskraftmaschinen mit einem Brennersystem |
DE10040868 | 2000-08-21 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1182399A2 true EP1182399A2 (de) | 2002-02-27 |
EP1182399A3 EP1182399A3 (de) | 2002-12-18 |
Family
ID=7653184
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP01116012A Withdrawn EP1182399A3 (de) | 2000-08-21 | 2001-07-02 | Verfahren zur Reduzierung thermoakustischer Schwingungen in Strömungskraftmaschinen mit einem Brennsystem |
Country Status (4)
Country | Link |
---|---|
US (1) | US20020029573A1 (de) |
EP (1) | EP1182399A3 (de) |
JP (1) | JP2002061521A (de) |
DE (1) | DE10040868A1 (de) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1429003A2 (de) * | 2002-12-07 | 2004-06-16 | Alstom Technology Ltd | Verfahren und Vorrichtung zur Beeinflussung thermoakustischer Schwingungen in Verbrennungssystemen |
CN109340816A (zh) * | 2018-10-09 | 2019-02-15 | 中国船舶重工集团公司第七0三研究所 | 振荡燃烧自反馈主动控制*** |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6918569B2 (en) * | 2002-02-28 | 2005-07-19 | Jansen's Aircraft Systems Controls, Inc. | Active combustion fuel valve |
DE10213682A1 (de) * | 2002-03-27 | 2003-10-09 | Alstom Switzerland Ltd | Verfahren und Vorrichtung zur Kontrolle von thermoakustischen Instabilitäten bzw. Schwingungen in einem Verbrennungssystem |
DE10257704A1 (de) * | 2002-12-11 | 2004-07-15 | Alstom Technology Ltd | Verfahren zur Verbrennung eines Brennstoffs |
AT504523B1 (de) * | 2007-01-04 | 2008-06-15 | Glueck Christoph Ing | Verfahren zum verfeuern von flüssigen brennstoffen |
US20210172376A1 (en) * | 2019-12-10 | 2021-06-10 | General Electric Company | Combustor ignition timing |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5428951A (en) * | 1993-08-16 | 1995-07-04 | Wilson; Kenneth | Method and apparatus for active control of combustion devices |
EP0962704A2 (de) * | 1998-05-29 | 1999-12-08 | United Technologies Corporation | Verfahren und Vorrichtung zum Treiben eines Brenners mit Gas |
EP0987495A1 (de) * | 1998-09-16 | 2000-03-22 | Abb Research Ltd. | Verfahren zum Minimieren thermoakustischer Schwingungen in Gasturbinenbrennkammern |
US20010027638A1 (en) * | 1998-09-10 | 2001-10-11 | Christian Oliver Paschereit | Method and apparatus for minimizing thermoacoustic vibrations in gas-turbine combustion chambers |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2239961A (en) * | 1990-01-02 | 1991-07-17 | Gen Electric | Control of combustion-induced instabilities |
DE4241729A1 (de) * | 1992-12-10 | 1994-06-16 | Stephan Dipl Ing Gleis | Aktuator zum Aufprägen von Massenstrom- bzw. Druckschwankungen auf unter Druck stehende Flüssigkeitsströme |
DE19504610C2 (de) * | 1995-02-13 | 2003-06-18 | Alstom | Vorrichtung zur Dämpfung thermoakustischer Druckschwingungen |
-
2000
- 2000-08-21 DE DE10040868A patent/DE10040868A1/de not_active Withdrawn
-
2001
- 2001-07-02 EP EP01116012A patent/EP1182399A3/de not_active Withdrawn
- 2001-08-08 JP JP2001241182A patent/JP2002061521A/ja not_active Withdrawn
- 2001-08-20 US US09/932,092 patent/US20020029573A1/en not_active Abandoned
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5428951A (en) * | 1993-08-16 | 1995-07-04 | Wilson; Kenneth | Method and apparatus for active control of combustion devices |
EP0962704A2 (de) * | 1998-05-29 | 1999-12-08 | United Technologies Corporation | Verfahren und Vorrichtung zum Treiben eines Brenners mit Gas |
US20010027638A1 (en) * | 1998-09-10 | 2001-10-11 | Christian Oliver Paschereit | Method and apparatus for minimizing thermoacoustic vibrations in gas-turbine combustion chambers |
EP0987495A1 (de) * | 1998-09-16 | 2000-03-22 | Abb Research Ltd. | Verfahren zum Minimieren thermoakustischer Schwingungen in Gasturbinenbrennkammern |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1429003A2 (de) * | 2002-12-07 | 2004-06-16 | Alstom Technology Ltd | Verfahren und Vorrichtung zur Beeinflussung thermoakustischer Schwingungen in Verbrennungssystemen |
EP1429003A3 (de) * | 2002-12-07 | 2005-04-27 | Alstom Technology Ltd | Verfahren und Vorrichtung zur Beeinflussung thermoakustischer Schwingungen in Verbrennungssystemen |
US7232308B2 (en) | 2002-12-07 | 2007-06-19 | Alstom Technology Ltd. | Method and device for affecting thermoacoustic oscillations in combustion systems |
CN109340816A (zh) * | 2018-10-09 | 2019-02-15 | 中国船舶重工集团公司第七0三研究所 | 振荡燃烧自反馈主动控制*** |
Also Published As
Publication number | Publication date |
---|---|
EP1182399A3 (de) | 2002-12-18 |
US20020029573A1 (en) | 2002-03-14 |
JP2002061521A (ja) | 2002-02-28 |
DE10040868A1 (de) | 2002-03-07 |
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