EP0269824A2 - Brûleur combiné à diffusion et à prémélange pour veilleuse - Google Patents

Brûleur combiné à diffusion et à prémélange pour veilleuse Download PDF

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Publication number
EP0269824A2
EP0269824A2 EP87115434A EP87115434A EP0269824A2 EP 0269824 A2 EP0269824 A2 EP 0269824A2 EP 87115434 A EP87115434 A EP 87115434A EP 87115434 A EP87115434 A EP 87115434A EP 0269824 A2 EP0269824 A2 EP 0269824A2
Authority
EP
European Patent Office
Prior art keywords
fuel
delivery pipe
diffusion
premix
nozzle
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.)
Granted
Application number
EP87115434A
Other languages
German (de)
English (en)
Other versions
EP0269824B1 (fr
EP0269824A3 (en
Inventor
Jennifer Waslo
Masayoshi Kuwata
Roy Marshall Washam
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.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by General Electric Co filed Critical General Electric Co
Publication of EP0269824A2 publication Critical patent/EP0269824A2/fr
Publication of EP0269824A3 publication Critical patent/EP0269824A3/en
Application granted granted Critical
Publication of EP0269824B1 publication Critical patent/EP0269824B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D11/00—Burners using a direct spraying action of liquid droplets or vaporised liquid into the combustion space
    • F23D11/005—Burners using a direct spraying action of liquid droplets or vaporised liquid into the combustion space with combinations of different spraying or vaporising 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
    • 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
    • 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
    • F23R3/34—Feeding into different combustion zones
    • F23R3/346—Feeding into different combustion zones for staged combustion

Definitions

  • This invention relates to gas turbine combustors; and, in particular, to improvements in gas turbine combustors for the further diminishment of air pollu­tants such as nitrogen oxides (NOx).
  • NOx nitrogen oxides
  • the secondary or center nozzle provides the flame source for the operation of the combustor.
  • the specific configuration of the patented invention includes an annular array of primary nozzles each of which discharges into the primary com­bustion chamber and a central secondary nozzle which discharges into the second combustion chamber.
  • These nozzles may all be described as diffusion nozzles in that each nozzle has an axial fuel delivery pipe and is surrounded at its discharge end by an air swirler which provides air for combustion to the fuel nozzle dis­charge.
  • the present inventors have discovered that further reduction in the production of NOx can be achieved by altering the design of the central or secondary nozzle such that is may be described as a combined premix and diffusion nozzle.
  • a relatively small amount of fuel is used to sustain a diffusion pilot whereas a premix section of the nozzle provides additional fuel for ignition of the main fuel supply from the upstream primary nozzles directed into the primary combustion chamber.
  • the present invention is especially applicable to gas turbine combustors of the type which include two combustion chambers separated by a venturi throat region.
  • An annular array of primary nozzles discharge fuel into an upstream or primary combustion chamber whereas a single central nozzle discharges fuel into a downstream or second combustion chamber.
  • the method of operation dictates that while under base load, the primary nozzles are flamed out whereas the single central or second nozzle supports combustion of premix fuel from the primary nozzles.
  • the single central second nozzle which has been characterized as a diffusion nozzle, is replaced by a combined diffusion and premix nozzle which reduces the fuel flow to the central diffusion flame from approximately 20 percent of the total fuel flow to about 2 percent of the total fuel flow for the entire combustor.
  • the design thus simultaneously minimizes the percentage of total fuel flow in the combustor that burns as a diffusion flame (with high NOx emissions) by allows sufficient heat input to ignite the main premixed flow by using the pilot premixed flow (which has low NOx emissions)
  • a gas turbine 12 includes a compressor 14, a combustor 16 and a turbine 18 repre­sented by a single blade. Although it is not specif deeplyically shown, it is well known that the turbine is drivingly connected to the compresssor along a common axis. The compressor pressurizes inlet air which is then turned in direction or reversed flowed to the combustor where it is used to cool the combustor and also used to provide air to the combustion process.
  • the gas turbine includes a plurality of combustors (one shown) which are located about the periphery of the gas turbine. In one particular gas turbine model there are fourteen such combustors disposed about the periphery of the gas turbine.
  • a transition duct 20 connects the outlet end of its particular combustor with the inlet end of the turbine to deliver the hot products of the combustion process to the turbine.
  • each combustor comprises a primary or upstream combustion chamber 24 and a second or downstream com­bustion chamber 26 separated by a venturi throat region 28.
  • the combustor is surrounded by a combustor flow sleeve 30 which channels compressor discharge air flow to the combustor.
  • the combustor is further surrounded by an outer casing 31 which is bolted to the turbine casing 32.
  • Primary nozzles 36 provide fuel delivery to the upstream combustor 24 and are arranged in an annular array around a central secondary nozzle 38.
  • each combustor may include six primary nozzles and one secondary nozzle.
  • fuel is delivered to the nozzles through plumbing 42 in a manner well known in the art and fully described in the aforementioned patent. Ignition in the primary combustor is caused by spark plug 48 not shown in Figure 2 and in adjacent combustors by means of crossfire tubes 50 also well known in the art.
  • a diffusion nozzle 36 includes a fuel delivery nozzle 54 and an annular swirler 56.
  • the nozzle 54 delivers only fuel which is then subsequently mixed with swirler air for combustion.
  • the secondary nozzle is also a diffusion nozzle as will be explained further.
  • the dual stage, dual mode combustor is designed to operate in a premix mode such that all of the primary nozzles are simply mixing fuel and air to be ignited by the diffusion flame supported by the second or central diffusion nozzle.
  • This premixing of the primary nozzle fuel and ignition by the secondary diffusion nozzle led to a lower NOx output in the combustor.
  • the applicants have dis­covered that a satisfactory pilot flame for the main premix flow from the upstream premix (primary) nozzles may be sustained by using a minimal diffusion pilot in combination with a central nozzle premix chamber.
  • the invention simultaneously mimizes the percentage of total fuel in the combustor that burns as a diffusion flame (with high NOx emissions) while allowing suffi­cient heat input to ignite the main premixed flow by using the premixed secondary or pilot flow.
  • the combined nozzle includes a diffusion pilot 62 having a fuel delivery pipe 64.
  • the fuel delivery pipe has an axial pipe 66 and a plurality of radial, blind ended fuel distribution tubes 68 which extend radially outwardly from the axial pipe.
  • the fuel distribution tubes each include a plurality of fuel discharge holes 70 which are directed downstream toward the discharge end of the combined nozzle.
  • the fuel distribution holes are sized so as to obtain the desired percentage of fuel flow into the premix chamber to be hereinafter described.
  • the diffusion pilot 62 further includes an air delivery pipe 74 coaxial with and surrounding the fuel delivery axial pipe 66.
  • the air input into the air delivery pipe is compressor discharge air which is reverse flowed around the combustor into the volume 76 defined by the flow sleeve 30 and the combustion chamber liner 78.
  • the diffusion pilot includes at its discharge end a first swirler annulus or diffusion pilot swirler 82 for the purpose of directing air delivery pipe discharge air to the diffusion pilot flame.
  • a premix chamber 84 is defined by a sleeve like truncated cone 85 which surrounds the diffusion pilot and includes a discharge end (see flow arrows) terminat­ing adjacent the diffusion pilot discharge end. Com­pressor discharge air is also reverse flowed into the premix chamber from volume 76 in a manner similar to the air delivery pipe.
  • the plurality of radial fuel dis­tribution tubes 68 extend through the air delivery pipe 74 and into the premix chamber annulus such that the fuel and air are mixed and delivered to a second swirler or premix chamber swirler 86 between the diffusion pilot and the premix chamber truncated cone 85.
  • a third swirler or central nozzle swirler 90 is located downstream from the discharge end of the com­bination diffusion and premix nozzle. This swirler is located between an extension or cup 92 on the discharge end of the pilot and the centerbody wall 95 of the primary combustion chamber. Compressor air is also reverse flowed to this swirler from the volume 76 surrounding the combustion liners.
  • the purpose of this third swirler is to provide stability for the diffusion and premix nozzle flame when combining with the primary premix flow from the primary combustor.
  • the required design of the swirlers 82, 86 and 90 would be known to practitioners in the combustion art and therefore requires no further description.
  • the premix chamber or truncated cone is formed of any metal suitable to use within the gas turbine environment.
  • fuel flow and combustion is initiated in the primary combustor until a predetermined mid-range load. At that time, fuel flow is split between the primary nozzles and the secondary nozzle to reach a desired load whereas ig­nition of the secondary nozzle is established. Fuel flow to the primary nozzles is then terminated to extinguish burning in the primary combustor. Fuel flow then is reestablished in the primary nozzles which then act as main premix chambers for the primary nozzle fuel flow whereas the second or central nozzle remains ignited and thus becomes a pilot flame for the primary main premix flow. At this point, according to prior practice, a diffusion flame using approximately twenty percent of the total combustor fuel flow would be left to produce a relatively high NOx output.
  • the foregoing invention produces less NOx while providing an opportunity to add to the fuel flow through the secondary nozzle because of the lower NOx output whereas the turn down ratio or the ability to operate under varying conditions is considerably widened because the diffusion pilot is subject to the premix flow of the pilot rather than the total overall premix flow from the surrounding primary nozzles.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Nozzles (AREA)
EP19870115434 1986-11-25 1987-10-21 Brûleur combiné à diffusion et à prémélange pour veilleuse Expired EP0269824B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US93488586A 1986-11-25 1986-11-25
US934885 1986-11-25

Publications (3)

Publication Number Publication Date
EP0269824A2 true EP0269824A2 (fr) 1988-06-08
EP0269824A3 EP0269824A3 (en) 1988-07-06
EP0269824B1 EP0269824B1 (fr) 1990-12-19

Family

ID=25466234

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19870115434 Expired EP0269824B1 (fr) 1986-11-25 1987-10-21 Brûleur combiné à diffusion et à prémélange pour veilleuse

Country Status (4)

Country Link
EP (1) EP0269824B1 (fr)
JP (1) JP2831641B2 (fr)
DE (1) DE3766807D1 (fr)
NO (1) NO166340C (fr)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0358437A1 (fr) * 1988-09-07 1990-03-14 Hitachi, Ltd. Dispositif de prémélange air-carburant pour une turbine à gaz
EP0399336A1 (fr) * 1989-05-24 1990-11-28 Hitachi, Ltd. Chambre de combustion et sa méthode d'opération
EP0466466A1 (fr) * 1990-07-10 1992-01-15 General Electric Company Brûleur mobile pour turbine à gaz et sa méthode d'opération
EP0488556A1 (fr) * 1990-11-27 1992-06-03 General Electric Company Injecteur secondaire de carburant à prémélange avec dispositif de tourbillonnement incorporé
US5193346A (en) * 1986-11-25 1993-03-16 General Electric Company Premixed secondary fuel nozzle with integral swirler
WO1993010400A1 (fr) * 1991-11-14 1993-05-27 United Technologies Corporation COMBUSTION A FAIBLE NIVEAU DE NOx PILOTEE PAR DES VEILLEUSES A EMISSION REDUITE DE NO¿x?
WO1993018289A1 (fr) * 1992-03-09 1993-09-16 Smeshannoe Tovarischestvo 'germes' Procede de conversion d'energie thermique en energie mecanique dans un moteur a turbine a gaz et moteur a turbine a gaz
EP0561591A2 (fr) * 1992-03-16 1993-09-22 General Electric Company Dispositif de tourbillonnement pour appareil de combustion
US5259184A (en) * 1992-03-30 1993-11-09 General Electric Company Dry low NOx single stage dual mode combustor construction for a gas turbine
EP0589520A1 (fr) * 1992-09-24 1994-03-30 NUOVOPIGNONE INDUSTRIE MECCANICHE E FONDERIA S.p.A. Système de combustion à pollution réduite pour turbines à gaz
EP0594127A1 (fr) * 1992-10-19 1994-04-27 Mitsubishi Jukogyo Kabushiki Kaisha Chambre de combustion pour turbine à gaz
US5435139A (en) * 1991-03-22 1995-07-25 Rolls-Royce Plc Removable combustor liner for gas turbine engine combustor
EP0672865A2 (fr) * 1994-03-14 1995-09-20 General Electric Company Buse à combustible d'une turbine avec double possibilité d'une combustion de diffusion et de prémélange et procédés de mise en oeuvre
DE19542644A1 (de) * 1995-11-17 1997-05-22 Abb Research Ltd Vormischverbrennung
WO2003006886A1 (fr) * 2001-07-10 2003-01-23 Pratt & Whitney Canada Corp. Premelangeur gaz-liquide
EP1852655A2 (fr) * 2006-05-04 2007-11-07 The General Electric Company Procédé et dispositif pour augmenter la flamme primaire et secondaire dans une chambre de combustion

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3183053B2 (ja) * 1994-07-20 2001-07-03 株式会社日立製作所 ガスタービン燃焼器及びガスタービン
JP5193088B2 (ja) * 2009-02-20 2013-05-08 三菱重工業株式会社 燃焼器及びガスタービン
US8919673B2 (en) * 2010-04-14 2014-12-30 General Electric Company Apparatus and method for a fuel nozzle
JP5804808B2 (ja) 2011-07-07 2015-11-04 三菱日立パワーシステムズ株式会社 ガスタービン燃焼器及びその燃焼振動減衰方法
US9016039B2 (en) * 2012-04-05 2015-04-28 General Electric Company Combustor and method for supplying fuel to a combustor

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2086476A1 (fr) * 1970-04-30 1971-12-31 Gen Electric
US3886728A (en) * 1974-05-01 1975-06-03 Gen Motors Corp Combustor prechamber
US3958416A (en) * 1974-12-12 1976-05-25 General Motors Corporation Combustion apparatus
DE2613589A1 (de) * 1975-04-19 1976-10-28 Nissan Motor Verbrennungseinrichtung fuer eine gasturbine
US4292801A (en) * 1979-07-11 1981-10-06 General Electric Company Dual stage-dual mode low nox combustor
US4389848A (en) * 1981-01-12 1983-06-28 United Technologies Corporation Burner construction for gas turbines
EP0095788A1 (fr) * 1982-05-28 1983-12-07 BBC Aktiengesellschaft Brown, Boveri & Cie. Chambre de combustion d'une turbine à gaz et sa méthode
EP0108361A1 (fr) * 1982-11-08 1984-05-16 Kraftwerk Union Aktiengesellschaft Brûleur de prémélange avec brûleur à diffusion intégré

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59202324A (ja) * 1983-05-04 1984-11-16 Hitachi Ltd ガスタ−ビン低ＮＯｘ燃焼器

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2086476A1 (fr) * 1970-04-30 1971-12-31 Gen Electric
US3886728A (en) * 1974-05-01 1975-06-03 Gen Motors Corp Combustor prechamber
US3958416A (en) * 1974-12-12 1976-05-25 General Motors Corporation Combustion apparatus
DE2613589A1 (de) * 1975-04-19 1976-10-28 Nissan Motor Verbrennungseinrichtung fuer eine gasturbine
US4292801A (en) * 1979-07-11 1981-10-06 General Electric Company Dual stage-dual mode low nox combustor
US4389848A (en) * 1981-01-12 1983-06-28 United Technologies Corporation Burner construction for gas turbines
EP0095788A1 (fr) * 1982-05-28 1983-12-07 BBC Aktiengesellschaft Brown, Boveri & Cie. Chambre de combustion d'une turbine à gaz et sa méthode
EP0108361A1 (fr) * 1982-11-08 1984-05-16 Kraftwerk Union Aktiengesellschaft Brûleur de prémélange avec brûleur à diffusion intégré

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5193346A (en) * 1986-11-25 1993-03-16 General Electric Company Premixed secondary fuel nozzle with integral swirler
EP0358437A1 (fr) * 1988-09-07 1990-03-14 Hitachi, Ltd. Dispositif de prémélange air-carburant pour une turbine à gaz
EP0399336A1 (fr) * 1989-05-24 1990-11-28 Hitachi, Ltd. Chambre de combustion et sa méthode d'opération
US5201181A (en) * 1989-05-24 1993-04-13 Hitachi, Ltd. Combustor and method of operating same
EP0466466A1 (fr) * 1990-07-10 1992-01-15 General Electric Company Brûleur mobile pour turbine à gaz et sa méthode d'opération
EP0488556A1 (fr) * 1990-11-27 1992-06-03 General Electric Company Injecteur secondaire de carburant à prémélange avec dispositif de tourbillonnement incorporé
US5435139A (en) * 1991-03-22 1995-07-25 Rolls-Royce Plc Removable combustor liner for gas turbine engine combustor
WO1993010400A1 (fr) * 1991-11-14 1993-05-27 United Technologies Corporation COMBUSTION A FAIBLE NIVEAU DE NOx PILOTEE PAR DES VEILLEUSES A EMISSION REDUITE DE NO¿x?
US5318436A (en) * 1991-11-14 1994-06-07 United Technologies Corporation Low NOx combustion piloted by low NOx pilots
WO1993018289A1 (fr) * 1992-03-09 1993-09-16 Smeshannoe Tovarischestvo 'germes' Procede de conversion d'energie thermique en energie mecanique dans un moteur a turbine a gaz et moteur a turbine a gaz
EP0561591A2 (fr) * 1992-03-16 1993-09-22 General Electric Company Dispositif de tourbillonnement pour appareil de combustion
EP0561591A3 (en) * 1992-03-16 1993-11-18 Gen Electric Swirler for combustor
US5259184A (en) * 1992-03-30 1993-11-09 General Electric Company Dry low NOx single stage dual mode combustor construction for a gas turbine
EP0589520A1 (fr) * 1992-09-24 1994-03-30 NUOVOPIGNONE INDUSTRIE MECCANICHE E FONDERIA S.p.A. Système de combustion à pollution réduite pour turbines à gaz
US5381652A (en) * 1992-09-24 1995-01-17 Nuovopignone Combustion system with low pollutant emission for gas turbines
EP0594127A1 (fr) * 1992-10-19 1994-04-27 Mitsubishi Jukogyo Kabushiki Kaisha Chambre de combustion pour turbine à gaz
US5410884A (en) * 1992-10-19 1995-05-02 Mitsubishi Jukogyo Kabushiki Kaisha Combustor for gas turbines with diverging pilot nozzle cone
EP0672865A2 (fr) * 1994-03-14 1995-09-20 General Electric Company Buse à combustible d'une turbine avec double possibilité d'une combustion de diffusion et de prémélange et procédés de mise en oeuvre
EP0672865A3 (fr) * 1994-03-14 1997-05-21 Gen Electric Buse à combustible d'une turbine avec double possibilité d'une combustion de diffusion et de prémélange et procédés de mise en oeuvre.
DE19542644A1 (de) * 1995-11-17 1997-05-22 Abb Research Ltd Vormischverbrennung
DE19542644B4 (de) * 1995-11-17 2008-12-11 Alstom Vormischverbrennung
WO2003006886A1 (fr) * 2001-07-10 2003-01-23 Pratt & Whitney Canada Corp. Premelangeur gaz-liquide
US6539721B2 (en) 2001-07-10 2003-04-01 Pratt & Whitney Canada Corp. Gas-liquid premixer
EP1852655A2 (fr) * 2006-05-04 2007-11-07 The General Electric Company Procédé et dispositif pour augmenter la flamme primaire et secondaire dans une chambre de combustion
EP1852655A3 (fr) * 2006-05-04 2014-10-01 General Electric Company Procédé et dispositif pour augmenter la flamme primaire et secondaire dans une chambre de combustion

Also Published As

Publication number Publication date
NO166340C (no) 1991-07-03
NO166340B (no) 1991-03-25
EP0269824B1 (fr) 1990-12-19
NO874893L (no) 1988-05-26
EP0269824A3 (en) 1988-07-06
JPH01137117A (ja) 1989-05-30
JP2831641B2 (ja) 1998-12-02
DE3766807D1 (de) 1991-01-31
NO874893D0 (no) 1987-11-24

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