US20140011143A1 - High perimeter stability burner - Google Patents

High perimeter stability burner Download PDF

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Publication number
US20140011143A1
US20140011143A1 US13/979,194 US201213979194A US2014011143A1 US 20140011143 A1 US20140011143 A1 US 20140011143A1 US 201213979194 A US201213979194 A US 201213979194A US 2014011143 A1 US2014011143 A1 US 2014011143A1
Authority
US
United States
Prior art keywords
diffuser
burner
radius
peripheral portions
longitudinally
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.)
Abandoned
Application number
US13/979,194
Other languages
English (en)
Inventor
Luca Barozzi
Francesco Fantoni
Antonio Acocella
Massimo Gilioli
Massimo Dotti
Tullo Paltrinieri
Paolo Gilli
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.)
Beckett Thermal Solutions SRL
Original Assignee
Individual
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 Individual filed Critical Individual
Assigned to WORGAS BRUCIATORI S.R.L. reassignment WORGAS BRUCIATORI S.R.L. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: Acocella, Antonio, BAROZZI, LUCA, DOTTI, MASSIMO, FANTONI, Francesco, GILIOLI, MASSIMO, GILLI, Paolo, PALTRINIERI, Tullio
Publication of US20140011143A1 publication Critical patent/US20140011143A1/en
Abandoned legal-status Critical Current

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D14/00Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/12Radiant burners
    • F23D14/14Radiant burners using screens or perforated plates
    • F23D14/145Radiant burners using screens or perforated plates combustion being stabilised at a screen or a perforated plate
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D14/00Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/12Radiant burners
    • F23D14/14Radiant burners using screens or perforated plates
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D14/00Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/46Details, e.g. noise reduction means
    • F23D14/48Nozzles
    • F23D14/58Nozzles characterised by the shape or arrangement of the outlet or outlets from the nozzle, e.g. of annular configuration
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D14/00Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/46Details, e.g. noise reduction means
    • F23D14/72Safety devices, e.g. operative in case of failure of gas supply
    • F23D14/74Preventing flame lift-off
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D2203/00Gaseous fuel burners
    • F23D2203/10Flame diffusing means
    • F23D2203/101Flame diffusing means characterised by surface shape
    • F23D2203/1017Flame diffusing means characterised by surface shape curved
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D2203/00Gaseous fuel burners
    • F23D2203/10Flame diffusing means
    • F23D2203/103Flame diffusing means using screens
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D2203/00Gaseous fuel burners
    • F23D2203/10Flame diffusing means
    • F23D2203/105Porous plates
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D2203/00Gaseous fuel burners
    • F23D2203/10Flame diffusing means
    • F23D2203/106Assemblies of different layers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D2209/00Safety arrangements
    • F23D2209/20Flame lift-off / stability
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D2212/00Burner material specifications
    • F23D2212/10Burner material specifications ceramic
    • F23D2212/103Fibres
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23DBURNERS
    • F23D2212/00Burner material specifications
    • F23D2212/20Burner material specifications metallic
    • F23D2212/203Particles
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23MCASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M2900/00Special features of, or arrangements for combustion chambers
    • F23M2900/13002Energy recovery by heat storage elements arranged in the combustion chamber

Definitions

  • the present invention relates to a high perimeter stability burner for a gas boiler.
  • Gas boilers of the prior art comprise: a conduit for supplying a burner with a premixed gas-air mixture, a burner for the production of heat through the combustion of said mixture in a combustion chamber, and possibly a support element which may be connected to the heat exchanger and/or to the supply conduit to ensure the closure of the combustion chamber and/or for positioning the burner with respect to such combustion chamber.
  • the burner comprises a diffuser through which the premixed fuel and air gas which determines a flame pattern for the production of heat is conveyed.
  • the diffuser comprises a wall provided with a plurality of openings and having an inner surface fluidically connected with the supply conduit, and thus in contact with the unburnt mixture, and an outer surface whereon the combustion occurs.
  • a distribution device, or distributor may also be provided arranged on the side of the diffuser opposite to the combustion surface, usually comprising a wall with a plurality of through openings, configured so as to distribute the gas-air mixture in a substantially uniform manner or however in the desired manner towards the wall of the diffuser.
  • the heat produced by the combustion on the outer side of the wall of the diffuser is conveyed through the hot fuel gases to a heat exchanger for heating a fluid, for example water, which is subsequently conveyed to a user, for example to a heating system of an industrial process, residential environments or the like and/or domestic water.
  • a fluid for example water
  • Such phenomenon of the flame moving away from the diffuser is particularly relevant at the ends of the diffuser.
  • the object of the present invention is to provide a burner capable of overcoming the aforementioned flame instability problems, and in particular the problem related to the flame detachment and which is simultaneously simple and inexpensive to produce.
  • a gas boiler burner comprising a diffuser, suitable for diffusing premixed fuel gases in a combustion chamber, each cross-section of said diffuser having a uniform radius of curvature, wherein said diffuser comprises a diffuser central portion and two diffuser longitudinally peripheral portions, said two diffuser longitudinally peripheral portions being connected together through said diffuser central portion, said diffuser central portion extending longitudinally in a direction perpendicular to the fuel gas flow for a length l greater than zero and having a cross-section shaped as a circumference arc having a radius r, each of said diffuser longitudinally peripheral portions being shaped as a portion of sphere having radius r.
  • Such particular configuration of the diffuser allows attaining a flame stability also in case of increase of the heating power and also at the ends of the diffuser.
  • the aforementioned configuration allows obtaining a flow direction of the fuel gases exiting from the diffuser whose component in the direction perpendicular to the surface of the diffuser at the edges thereof is substantially null.
  • it is possible to reduce the mixture flow at the edges and prevent the flame detachment phenomenon, also with high power modulations.
  • gas flow direction is used to indicate the main direction of flow of the gases.
  • the expression “the cross-section has a uniform radius of curvature” is used to indicate that each point of the cross-section has the same radius of curvature, i.e. it belongs to the same hypothetical circumference having such radius.
  • FIG. 1 is a longitudinal sectional view of a boiler portion comprising a gas burner according to the present invention
  • FIG. 2 is a perspective view of a gas boiler burner according to a first embodiment of the invention
  • FIG. 3 is a perspective view of a gas boiler burner according to an embodiment of the invention, mounted on a framework;
  • FIG. 4 is a side view of the burner of FIG. 3 ;
  • FIG. 5 is the view along the cross-section B-B of the burner of FIG. 4 ;
  • FIGS. 6 a - 6 c show the vectorial breakdown of some flow lines of the fuel gases along the section of FIG. 5 .
  • a gas boiler burner is wholly indicated with reference number 1 .
  • reference 1 indicates a burner which produces heat through the combustion of a premixed fuel gas, generally comprising fuel gas and air.
  • a premixed fuel gas generally comprising fuel gas and air.
  • fuel gases are completely premixed, i.e. no further component is added to the mixture supplied to the burner.
  • the burner 1 comprises a diffuser 2 , which is suitable for diffusing fuel gases in a combustion chamber 3 (indicated with a dotted line in FIG. 1 ).
  • the burner 1 is mounted on a framework 9 .
  • the latter may be connected to the combustion chamber 3 through connection portions.
  • the framework 9 further delimits an opening for the passage of the fuel and air mixture.
  • the diffuser 2 includes a wall provided with a plurality of openings whose inner surface is fluidically connected with the gas supply conduit. The combustion occurs on the outer surface of such wall.
  • the diffuser 2 may comprise a distributor 4 of the known type, suitable for distributing the mixture to the diffuser 2 and arranged on the side of the diffuser 2 opposite to the combustion chamber 3 .
  • FIG. 1 also shows a schematic representation of a heat exchanger 6 in contact with the combustion chamber 3 , which is suitable for receiving the heat produced by the combustion on the outer side of the wall of the diffuser 2 .
  • a longitudinal direction ⁇ As shown in FIG. 2 , three main directions have been identified: a longitudinal direction ⁇ , a transverse direction ⁇ and a radial direction ⁇ .
  • the longitudinal direction a and the transverse direction are orthogonal to each other and they are both orthogonal to the direction of flow of the gases entering into the burner 1 , which is indicated in the figures with the arrows 7 .
  • each cross-section of said diffuser 2 has a uniform radius of curvature.
  • each section obtained intersecting the diffuser 2 with a plane parallel to the plane B-B of FIG. 4 has a single radius of curvature, i.e. each point of the section belongs to an ideal circumference having such radius of curvature.
  • the diffuser comprises a diffuser central portion 10 and two diffuser longitudinally peripheral portions 5 , in which said two diffuser longitudinally peripheral portions 5 are connected to each other by said diffuser central portion 10 .
  • the diffuser central portion 10 extends longitudinally in a direction perpendicular to the flow of the fuel gases, i.e. in the longitudinal direction ⁇ , over a length l greater than zero.
  • the diffuser central portion 10 has a cross-section shaped as a circumference arc having a radius r, as shown in FIG. 5 .
  • the cross-section is preferably a semi-circumference.
  • the diffuser central portion 10 extends transversely over a length equivalent to 2r.
  • Each of said diffuser longitudinally peripheral portions 5 is shaped as a portion of sphere having radius r, as shown in FIG. 4 .
  • each of said portions is shaped as a quarter of sphere.
  • the radius of the spherical portion which forms each peripheral longitudinal portion of the diffuser 5 has a length equivalent to the radius of the cross-section of the central diffuser portion 10 .
  • the burner 1 also comprises a distributor associated to the diffuser 2 and suitable for distributing the fuel gases on the diffuser 2 , which has a configuration substantially equivalent to the configuration of the diffuser 2 . This is particularly observable in FIG. 5 .
  • Said distributor 4 comprises a sheet provided with openings or a metal mesh or a porous material.
  • the diffuser 2 instead, comprises a mesh made of metal or ceramic fibres or a compact material having openings or a porous material.
  • the diffuser is connected to a framework 9 which is arranged substantially perpendicular to the direction of flow of the fuel gases entering the burner 1 , indicated by the arrows 7 .
  • FIGS. 6 a - 6 c the arrow indicated with the reference number 7 ′ shows the direction of flow of the gases exiting from the burner 1 .
  • Such phenomenon compensates the temperature drop typical of the ends for connection to the framework 9 , thus avoiding the flame detachment in such critical areas.
  • each longitudinally peripheral portion of the diffuser 5 is shaped as a circumference arc having a radius r, thus the edges of the longitudinal section of the diffuser 2 have the same characteristics of the edges of the cross-section of the diffuser 2 .
  • the normal component of the direction of flow of the exiting gases is minimum along all the perimeter edges of the diffuser 2 and thus the flame detachment phenomenon, critical in such areas, is controlled.
  • gas boiler burner according to the present invention may be subjected, by a man skilled in the art, with the aim of meeting contingent and specific requirements, to further modifications and variants all falling within scope of protection of the invention.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Gas Burners (AREA)
  • Pressure-Spray And Ultrasonic-Wave- Spray Burners (AREA)
US13/979,194 2011-01-12 2012-01-11 High perimeter stability burner Abandoned US20140011143A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
ITMI2011A000019 2011-01-12
ITMI2011A000019A IT1406865B1 (it) 2011-01-12 2011-01-12 Bruciatore ad elevata stabilita' perimetrale
PCT/IB2012/050135 WO2012095799A2 (en) 2011-01-12 2012-01-11 High perimeter stability burner

Publications (1)

Publication Number Publication Date
US20140011143A1 true US20140011143A1 (en) 2014-01-09

Family

ID=43975364

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/979,194 Abandoned US20140011143A1 (en) 2011-01-12 2012-01-11 High perimeter stability burner

Country Status (8)

Country Link
US (1) US20140011143A1 (ko)
EP (1) EP2663807B1 (ko)
KR (1) KR101965676B1 (ko)
CN (1) CN103429959B (ko)
IT (1) IT1406865B1 (ko)
RU (1) RU2585669C2 (ko)
UA (1) UA112538C2 (ko)
WO (1) WO2012095799A2 (ko)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018050310A1 (en) * 2016-09-13 2018-03-22 Bekaert Combustion Technology B.V. Premix gas burner
CN108180475A (zh) * 2018-01-10 2018-06-19 沈阳工程学院 一种轴向和径向稳燃的预混气体多孔介质燃烧器
US20190101308A1 (en) * 2017-10-03 2019-04-04 Lennox Industries Inc. PRE-MIX BURNER ASSEMBLY FOR LOW NOx EMISSION FURNACE
US10711998B2 (en) 2017-10-03 2020-07-14 Lennox Industries Inc. Fresh air intake for low NOx emission furnace
US10711997B2 (en) 2017-10-03 2020-07-14 Lennox Industries Inc. Burner box liner for low NOx emission furnace
US11162677B2 (en) 2019-01-18 2021-11-02 Lennox Industries Inc. Air intake coupling with noise suppression for low NOx emission furnace

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ITMI20121643A1 (it) * 2012-10-02 2014-04-03 Worgas Bruciatori Srl Bruciatore con diffusore in tessuto
ITMI20131465A1 (it) * 2013-09-06 2015-03-07 Worgas Bruciatori Srl Bruciatore e metodo per la fabbricazione di un bruciatore
ITMI20131968A1 (it) * 2013-11-26 2015-05-27 Worgas Bruciatori Srl Bruciatore
ITUA20164076A1 (it) * 2016-06-03 2017-12-03 Worgas Bruciatori Srl Bruciatore
CN110832253A (zh) * 2017-07-13 2020-02-21 贝卡尔特燃烧技术股份有限公司 预混合气体燃烧器
EP3781866B1 (en) * 2018-04-19 2022-05-04 Bekaert Combustion Technology B.V. Premix gas burner
IT202000005191A1 (it) * 2020-03-11 2021-09-11 Beckett Thermal Solutions S R L Bruciatore
CN113239537B (zh) * 2021-05-11 2023-10-27 扬州扬杰电子科技股份有限公司 一种扩散片合金块的高周波加热功率确定方法

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Publication number Priority date Publication date Assignee Title
US3360028A (en) * 1966-01-03 1967-12-26 Caloric Corp Gas burning infrared ray generator
US3401000A (en) * 1966-06-29 1968-09-10 Caloric Corp Domed screen radiant burner
DE19648651A1 (de) * 1995-11-24 1997-05-28 Vaillant Joh Gmbh & Co Verfahren zur Herstellung eines Brenners
EP1030107A1 (en) * 1999-02-18 2000-08-23 Worgas Bruciatori S.R.L. Premix gas burner
US20060251998A1 (en) * 2003-04-18 2006-11-09 Dinand Lamberts Metal burner membrane

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1105757A (en) * 1966-10-25 1968-03-13 Caloric Internat Inc Improvements in or relating to radiant burners
SU434226A1 (ru) * 1971-11-16 1974-06-30 А. М. Левин, С. Салиходжаев, Асадуллаев , Я. И. Мошн гер Радиационная горелка
IT1263759B (it) * 1993-01-15 1996-08-29 Enrico Sebastiani Apparecchio per la combustione di gas con un bruciatore atmosferico a premiscelazione iperstechiometrica e metodo per la regolazione dell'aria aspirata particolarmente in fase di accensione
JP3684345B2 (ja) * 2001-11-05 2005-08-17 リンナイ株式会社 ガスこんろ

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3360028A (en) * 1966-01-03 1967-12-26 Caloric Corp Gas burning infrared ray generator
US3401000A (en) * 1966-06-29 1968-09-10 Caloric Corp Domed screen radiant burner
DE19648651A1 (de) * 1995-11-24 1997-05-28 Vaillant Joh Gmbh & Co Verfahren zur Herstellung eines Brenners
EP1030107A1 (en) * 1999-02-18 2000-08-23 Worgas Bruciatori S.R.L. Premix gas burner
US20060251998A1 (en) * 2003-04-18 2006-11-09 Dinand Lamberts Metal burner membrane

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190045211A (ko) * 2016-09-13 2019-05-02 베카에르트 컴버스천 테크놀러지 비.브이. 예혼합 가스 버너
WO2018050578A1 (en) 2016-09-13 2018-03-22 Bekaert Combustion Technology B.V. Premix gas burner
KR102368554B1 (ko) * 2016-09-13 2022-03-02 베카에르트 컴버스천 테크놀러지 비.브이. 예혼합 가스 버너
WO2018050310A1 (en) * 2016-09-13 2018-03-22 Bekaert Combustion Technology B.V. Premix gas burner
US20190101308A1 (en) * 2017-10-03 2019-04-04 Lennox Industries Inc. PRE-MIX BURNER ASSEMBLY FOR LOW NOx EMISSION FURNACE
US10711998B2 (en) 2017-10-03 2020-07-14 Lennox Industries Inc. Fresh air intake for low NOx emission furnace
US10711997B2 (en) 2017-10-03 2020-07-14 Lennox Industries Inc. Burner box liner for low NOx emission furnace
US11187433B2 (en) * 2017-10-03 2021-11-30 Lennox Industries Inc. Pre-mix burner assembly for low NOx emission furnace
US11543123B2 (en) 2017-10-03 2023-01-03 Lennox Industries Inc. Burner box liner for low NOx emission furnace
US11598557B2 (en) 2017-10-03 2023-03-07 Lennox Industries Inc. Pre-mix burner assembly for low NOx emission furnace
US11808449B2 (en) 2017-10-03 2023-11-07 Lennox Industries Inc. Fresh air intake for low NOx emission furnace
CN108180475A (zh) * 2018-01-10 2018-06-19 沈阳工程学院 一种轴向和径向稳燃的预混气体多孔介质燃烧器
US11162677B2 (en) 2019-01-18 2021-11-02 Lennox Industries Inc. Air intake coupling with noise suppression for low NOx emission furnace

Also Published As

Publication number Publication date
IT1406865B1 (it) 2014-03-14
EP2663807B1 (en) 2017-04-05
CN103429959B (zh) 2015-09-30
RU2013137417A (ru) 2015-02-20
RU2585669C2 (ru) 2016-06-10
WO2012095799A2 (en) 2012-07-19
KR20140051818A (ko) 2014-05-02
ITMI20110019A1 (it) 2012-07-13
UA112538C2 (uk) 2016-09-26
WO2012095799A3 (en) 2012-11-29
EP2663807A2 (en) 2013-11-20
KR101965676B1 (ko) 2019-04-04
CN103429959A (zh) 2013-12-04

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Legal Events

Date Code Title Description
AS Assignment

Owner name: WORGAS BRUCIATORI S.R.L., ITALY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BAROZZI, LUCA;FANTONI, FRANCESCO;ACOCELLA, ANTONIO;AND OTHERS;REEL/FRAME:031165/0293

Effective date: 20130731

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION