EP0643267B1 - Verfahren und vorrichtung zur verbrennung von vorgemischtem gas - Google Patents

Verfahren und vorrichtung zur verbrennung von vorgemischtem gas Download PDF

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Publication number
EP0643267B1
EP0643267B1 EP94908507A EP94908507A EP0643267B1 EP 0643267 B1 EP0643267 B1 EP 0643267B1 EP 94908507 A EP94908507 A EP 94908507A EP 94908507 A EP94908507 A EP 94908507A EP 0643267 B1 EP0643267 B1 EP 0643267B1
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EP
European Patent Office
Prior art keywords
fuel
gas
premixed gas
combustion
premixed
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.)
Expired - Lifetime
Application number
EP94908507A
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English (en)
French (fr)
Other versions
EP0643267A1 (de
EP0643267A4 (de
Inventor
Shigemi Takasago Mach. Works Mitsubishi Mandai
Katsunori Takasago Mach. Works Mitsubishi Tanaka
Nobuo Takasago Research & Development Ctr. SATO
Satoshi Takasago Res. & Dev. Ctr. TANIMURA
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Heavy Industries Ltd
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Mitsubishi Heavy Industries Ltd
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Filing date
Publication date
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Publication of EP0643267A1 publication Critical patent/EP0643267A1/de
Publication of EP0643267A4 publication Critical patent/EP0643267A4/de
Application granted granted Critical
Publication of EP0643267B1 publication Critical patent/EP0643267B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
    • F23L7/00—Supplying non-combustible liquids or gases, other than air, to the fire, e.g. oxygen, steam
    • F23L7/002—Supplying water
    • F23L7/005—Evaporated water; Steam
    • 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
    • F23R3/02—Continuous combustion chambers using liquid or gaseous fuel characterised by the air-flow or gas-flow configuration
    • F23R3/04—Air inlet arrangements
    • F23R3/10—Air inlet arrangements for primary air
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D2210/00—Noise abatement

Definitions

  • This invention relates to a method for the combustion of a premixed gas in a combustor having a fuel-air premixing nozzle and useful for effecting low-NO x combustion and a combustor therefor.
  • This invention can be applied to such combustors as gas turbine combustors, boilers, and furnaces for use in chemical industry.
  • FIG. 3 illustrates a part of a burner based on the conventional method for the combustion of a premixed gas.
  • reference numeral 1 designates a premixing nozzle
  • 2 designates a premixed gas
  • 3 designates a flame holder
  • 4 designates a flame
  • 5 designates a circulating or staying hot gas
  • 6 designates a pilot nozzle
  • 7 designates a pilot fuel.
  • the premixed gas 2 injected through the premixing nozzle 1 into the combustion chamber burns so as to go round the flame holder 3, thus forming downstream a circulating hot gas 5 serving for flame holding.
  • the combustion rate of the premixed gas i.e., the velocity at which the flame advances into the unburned mixture
  • the fuel concentration may cause marked variation in the resulting combustion rate.
  • variation in combustion rate causes variation in flame length and may eventually lead to the development of combustive vibration.
  • a combustor primarily for a gas turbine which employs swirl flame stabilization is known. Vortex induced centrifugal forces and hot gas recirculation are employed for flame stabilization.
  • the dual stage combustor operates in two modes, stable fuel air strata mode and low emission mode.
  • the combustor comprises a cylindrical, elongated casing which has an upstream section and a downstream section connected by a radially extending transition section, and a liquid fuel injector concentrically disposed in the upstream casing section.
  • the injector and the upstream casing section form an annular combustion air passage with an inlet.
  • a set of radially oriented, equiangularly spaced, longitudinally extending swirl vanes In the combustion air passage adjacent the inlet and extending between the upstream casing section and the injector is a set of radially oriented, equiangularly spaced, longitudinally extending swirl vanes.
  • Fuel is introduced into the injector through a fuel line communicating through a radially extending passage in the injector with an annular passage.
  • the annular fuel passage extends axially downstream and then angles outwardly and opens onto the exterior surface of the injector.
  • Downstream from the fuel passage outlet is a fuel film zone in which the swirling combustion air spreads and thins the fuel into a stratified film. Where the film of fuel leaves the injector surface, it attaches to the inner boundary of the combustion air annulus.
  • the injector has a second, annular, radially and axially extending slot through which air is discharged to drive the combustor into the low emission operating mode.
  • the air discharged through the second slot forms a swirling or rotating annulus which isolates the hot gases in a recirculation zone from the fuel.
  • Initial air and fuel are discharged separately and form a stratified fuel-air charge.
  • Initial ignition is effected by the hot gases in the inner recirculation zone.
  • fuel and air are mixed after the fuel is discharged into the nozzle portion which also contains the second outlet for air.
  • the fuel-gas mixture is formed with the injected air (neutral gas).
  • the present invention has been made for the purpose of solving the above-described problems encountered with the known method and combustor and has for its object the provision of a method and combustor for the combustion of a premixed gas which can minimize the development of combustive vibration due to variation in the fuel concentration of the premixed gas.
  • a neutral fluid is fed between the premixed gas layer and the hot gas, so that a flame is not propagated directly from the hot gas to the premixed gas. Instead, a mid-temperature gas is generated by the mixing and diffusion of the hot gas and the neutral fluid. Thereafter, the premixed gas is burned as a result of the mixing and diffusion of the mid-temperature gas and the premixed gas.
  • the mechanism by which the premixed gas is burned is such that the hot gas and the premixed gas intermingle with each other, during this process the premixed gas is heated by the heat transferred from the hot gas, and combustion is initiated when the combustion starting temperature is reached.
  • the premixed gas is burned under mixing and diffusion rate control, as contrasted with an ordinary premixed flame in which combustion is effected by flame propagation. Consequently, it is possible to achieve combustion which is little affected by the fuel concentration of the premixed gas.
  • diffusion means that the hot gas and the premixed gas intermingle with each other
  • rate control means the controlling of the rate of such diffusion.
  • Diffusion rate control means the controlling of the rate at which the hot gas and the premixed gas intermingle with each other.
  • the flame temperature in this mixing region is low and the production of NO x in this region is minimized.
  • the premixed gas is burned under diffusion rate control, the main flame is long, and heat generation or heat generation quotient can be spread in space, so that combustive vibration can be prevented.
  • the reason why combustive vibration can be prevented is that the combustion pressure is reduced by dispersion of the heat generation and, moreover, the variation of flame length relative to the total flame length becomes smaller as a result of the prolongation of the flame.
  • heat generation quotient means the per area combustion (dQ/dx) of fuel (Q) with respect to the axial distance (x) of a combustor.
  • FIG. 1 illustrates an exemplary burner for carrying out the method of the present invention.
  • the same elements as shown in FIG. 3 are designated by the same reference numerals and no detailed explanation thereof is given.
  • a passage for feeding a neutral fluid 8 is formed between a premixing nozzle 1 and a pilot nozzle 6.
  • the orifice for injecting the neutral fluid 8 into the combustion chamber is configured so as to cause the neutral fluid 8 to flow out along the inner wall surface of a flame holder 3.
  • the neutral fluid 8 is a fluid containing no fuel and may comprise, for example, air, exhaust gas, steam or the like.
  • a neutral fluid is fed between a layer of a premixed gas 2 injected through the premixing nozzle 1 and a circulating hot gas 5, so that the premixed gas 2 injected through the premixing nozzle 1 does not come into direct contact with the hot gas 5.
  • the neutral fluid 8 is first mixed with the hot gas 5 to generate a mid-temperature gas. Then, in a downward region, this mid-temperature gas is mixed with the premixed gas 2 to form a flame 4.
  • the premixed gas 2 separated from the hot gas 5 by the neutral fluid 8 can be burned under diffusion rate control, so that a long main flame results. This means that the heat generation quotient can be spatially spread and small to prevent combustive vibration.
  • FIG. 2 is a graph showing the states of combustive vibration when combustion was effected in a burner using air as the neutral fluid 8 according to the method of the present invention and in a conventional burner.
  • the ordinate shows the internal pressure fluctuation of the combustor which serves as a measure of combustive vibration
  • the abscissa shows the proportion of the pilot fuel (i.e., the pilot fuel 7 for the formation of a diffusion flame) to the total fuel (i.e., the main fuel plus the pilot fuel).
  • FIG. 2 indicates that, regardless of the proportion of the pilot fuel, the internal pressure fluctuation ratio is lower in the presence of a neutral fluid (the present invention) than in the absence of a neutral fluid (the prior art). That is, FIG. 2 indicates less combustive vibration in the presence of a neutral fluid, demonstrating the effects of the present invention.
  • the present invention is not limited to the burner design illustrated in FIG. 1, but comprehends all combustors involving the formation of a circulating flow wherein a neutral fluid is fed between the circulating flow and the premixed gas.
  • the present invention can be applied to combustors having various flame-holding plates and combustors forming a circulating flow or a stagnation point in a region having an abruptly expanded flow path.

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)
  • Pre-Mixing And Non-Premixing Gas Burner (AREA)

Claims (2)

  1. Ein Verfahren zum Minimieren von Verbrennungsvibrationen bei der Verbrennung eines vorgemischten Gases (2) in einem Brenner mit einer Kraftstoff/Luft-Vormischdüse (1), welche einen Flammenhalter (3) zum Halten einer Flamme aufweist, wobei das Verfahren aufweist:
       Zuführen eines Fluides (8), welches keinen Kraftstoff enthält, zwischen eine vorgemischte Gasschicht, welche durch Einspritzen des vorgemischten Gases durch die Vormischdüse gebildet wird und ein zirkulierendes Heißgas (5), welches als Ergebnis der Verbrennung des vorgemischten Gases gebildet wird, und Richten des Fluides (8), so daß dieses entlang einer Wandfläche des Flammenhalters ausströmt, wobei das Heißgas einen zirkulierenden Fluß in einem Bereich stromab des Auslasses der Vormischdüse bildet.
  2. Ein Brenner mit:
    einer Leerlaufdüse (6);
    einer Brennstoff/Luft-Vormischdüse (1) zum Einspritzen eines vorgemischten Brennstoff/Luft-Gases (2), welche um die Leerlaufdüse herum und koaxial zur Leerlaufdüse angeordnet ist;
    einem Flammenhalter (3), der am Auslaß der Brennstoff/Luft-Vormischdüse angeordnet ist, um eine Flamme zu halten; und
    einem Durchlaß zur Zufuhr eines Fluides (8), welches keinen Brennstoff enthält, der zwischen der Leerlaufdüse und der Brennstoff/Luft-Vormischdüse angeordnet ist, wobei der Durchlaß so angeordnet ist, daß er das Fluid (8) so richtet, daß dieses entlang einer Wandfläche des Flammenhalters (3) so fließt, daß das Fluid zwischen dem vorgemischten Brennstoff/Luft-Gas (2) und einem zirkulierenden Heißgas (5) fließt, welches als Ergebnis der Verbrennung des vorgemischten Gas gebildet wird, wobei das zirkulierende Heißgas (5) einen zirkulierenden Fluß in einem Bereich stromab des Auslasses der Vormischdüse (1) bildet.
EP94908507A 1993-03-08 1994-03-08 Verfahren und vorrichtung zur verbrennung von vorgemischtem gas Expired - Lifetime EP0643267B1 (de)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP72948/93 1993-03-08
JP07294893A JP3197103B2 (ja) 1993-03-08 1993-03-08 予混合気の燃焼方法
JP7294893 1993-03-08
PCT/JP1994/000363 WO1994020793A1 (en) 1993-03-08 1994-03-08 Premixed gas burning method and combustor

Publications (3)

Publication Number Publication Date
EP0643267A1 EP0643267A1 (de) 1995-03-15
EP0643267A4 EP0643267A4 (de) 1996-03-27
EP0643267B1 true EP0643267B1 (de) 1999-07-28

Family

ID=13504120

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94908507A Expired - Lifetime EP0643267B1 (de) 1993-03-08 1994-03-08 Verfahren und vorrichtung zur verbrennung von vorgemischtem gas

Country Status (5)

Country Link
EP (1) EP0643267B1 (de)
JP (1) JP3197103B2 (de)
CA (1) CA2134893C (de)
DE (1) DE69419679T2 (de)
WO (1) WO1994020793A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4431811A1 (de) * 2023-03-13 2024-09-18 RTX Corporation Asymmetrische einführung von dampf in eine turbinenmotorbrennkammer

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JPS63253147A (ja) * 1987-04-09 1988-10-20 Nissan Motor Co Ltd 内燃機関のアイドル回転数制御装置
EP0754908B2 (de) * 1995-07-20 2001-04-18 DVGW Deutscher Verein des Gas- und Wasserfaches -Technisch-wissenschaftliche Vereinigung- Verfahren und Vorrichtung zur Unterdrückung von Flammen-/Druckschwingungen bei einer Feuerung
US5987875A (en) * 1997-07-14 1999-11-23 Siemens Westinghouse Power Corporation Pilot nozzle steam injection for reduced NOx emissions, and method
JPH1183017A (ja) * 1997-09-08 1999-03-26 Mitsubishi Heavy Ind Ltd ガスタービン用燃焼器
DE69930455T2 (de) 1998-11-12 2006-11-23 Mitsubishi Heavy Industries, Ltd. Gasturbinenbrennkammer
DE10000415A1 (de) * 2000-01-07 2001-09-06 Alstom Power Schweiz Ag Baden Verfahren und Vorrichtung zur Unterdrückung von Strömungswirbeln innerhalb einer Strömungskraftmaschine
JP2001254946A (ja) 2000-03-14 2001-09-21 Mitsubishi Heavy Ind Ltd ガスタービン燃焼器
JP2003028425A (ja) * 2001-07-17 2003-01-29 Mitsubishi Heavy Ind Ltd 予混合燃焼器のパイロットバーナー、予混合燃焼器、およびガスタービン
DE112004002704B4 (de) * 2004-03-03 2011-04-07 Mitsubishi Heavy Industries, Ltd. Verbrennungsanlage
JP2007162998A (ja) 2005-12-13 2007-06-28 Kawasaki Heavy Ind Ltd ガスタービンエンジンの燃料噴霧装置
JP4829315B2 (ja) * 2009-01-16 2011-12-07 川崎重工業株式会社 ガスタービンエンジンの燃料噴霧装置
JP6004976B2 (ja) * 2013-03-21 2016-10-12 三菱重工業株式会社 燃焼器及びガスタービン
US9781307B2 (en) 2014-11-14 2017-10-03 Sawgrass Technologies, Inc. Networked digital imaging customization
US9302468B1 (en) 2014-11-14 2016-04-05 Ming Xu Digital customizer system and method
CN105953219B (zh) * 2016-06-21 2018-01-16 上海齐耀热能工程有限公司 无焰燃烧装置

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US3724207A (en) * 1971-08-05 1973-04-03 Gen Motors Corp Combustion apparatus
GB1427146A (en) * 1972-09-07 1976-03-10 Rolls Royce Combustion apparatus for gas turbine engines
GB1429677A (en) * 1973-03-20 1976-03-24 Rolls Royce Gas turbine engine combustion equipment
US4373325A (en) * 1980-03-07 1983-02-15 International Harvester Company Combustors
JPS6122106A (ja) * 1984-07-10 1986-01-30 Hitachi Ltd ガスタ−ビン燃焼器
JPH01118023A (ja) * 1987-10-30 1989-05-10 Hitachi Ltd ガスタービン燃焼器
JPH04340020A (ja) * 1991-05-15 1992-11-26 Mitsubishi Heavy Ind Ltd ガスタービン燃焼器

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4431811A1 (de) * 2023-03-13 2024-09-18 RTX Corporation Asymmetrische einführung von dampf in eine turbinenmotorbrennkammer

Also Published As

Publication number Publication date
JP3197103B2 (ja) 2001-08-13
DE69419679D1 (de) 1999-09-02
EP0643267A1 (de) 1995-03-15
WO1994020793A1 (en) 1994-09-15
DE69419679T2 (de) 2000-03-02
JPH06257750A (ja) 1994-09-16
EP0643267A4 (de) 1996-03-27
CA2134893A1 (en) 1994-09-15
CA2134893C (en) 1999-09-07

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