US3869865A - Devices for prevaporising liquid fuel - Google Patents

Devices for prevaporising liquid fuel Download PDF

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Publication number
US3869865A
US3869865A US372514A US37251473A US3869865A US 3869865 A US3869865 A US 3869865A US 372514 A US372514 A US 372514A US 37251473 A US37251473 A US 37251473A US 3869865 A US3869865 A US 3869865A
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United States
Prior art keywords
agent
gaseous
comburrent
source
liquid fuel
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Expired - Lifetime
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US372514A
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English (en)
Inventor
Armand Jean-Baptiste Lacroix
Herve Alain Quillevere
Bernard Andre Cantaloube
Jacques Emile Jules Caruel
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Safran Aircraft Engines SAS
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SNECMA SAS
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    • 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
    • F23R3/30—Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply comprising fuel prevapourising devices
    • F23R3/32—Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply comprising fuel prevapourising devices being tubular

Definitions

  • ABSTRACT A device for prevaporising liquid fuel, designed for fitting to a combustion system comprising a combustion chamber, a source of liquid fuel and a source of gaseous comburrent agent, said device being of the type which comprises, projecting into the combustion chamber, a hollow structure incorporating a body and at least one arm attached to said body and having at least one portion extending transversely of the general direction of said body, the latter comprising an entry portion which communicates with said sources of liq uid fuel and gaseous comburrent agent, and said arm having an exit portion which opens into the combustion chamber and through which, in operation, there is discharged a mixture of gaseous comburrent agent and at least partially vaporised fuel, wherein said hollow structure comprises, in a zone which incorporates the transverse portion of said arm, a double-walled system constituted by an internal wall and an external wall which together delimit two separate passages, namely a central passage communicating both with the source of gaseous comburrent agent and with the liquid fuel
  • the present invention relates to a device for prevaporising liquid fuel, designed for fitting to a combustion system comprising a combustion chamber, a liquid fuel source and a source of gaseous comburrent agent, said device being of the kind comprising, projecting into said combustion chamber, a hollow structure incorporating a body and at least one arm fixed to said body and having at least one portion extending transversely of the general direction of said body, the latter comprising an input portion communicating with said sources of liquid fuel and gaseous comburrent agent, and said arm having an exit portion which opens into the combustion chamber and through which, in operation, there is discharged a mixture of gaseous comburrent agent and at least partially vaporised fuel.
  • the combustion system in question may, in particular, form part of a gas turbine engine such as a turbojet engine.
  • One of the problems posed by the application of a hollow structure of the aforedescribed kind, is that of protecting it against local overheating, in particular of the zone of such arm or arms.
  • This structure is subjected to the extremely high temperatures which prevail in the upstream part of the combustion chamber, and it can also happen that inside said structure premature combustion of the fuel flowing through it takes place.
  • a particularly effective coolant for the hollow structure is constituted by fuel in the course of prevaporisation, which is present inside said structure.
  • the object of the present invention in a general way, is to diminish the risk of overheating of the hollow structure due to one or the other of the two aforesaid causes.
  • the hollow structure (which is of the kind defined hereinbefore) comprises, in a zone which includes the transverse portion of the arm, a double-walled system constituted by an internal wall and an external wall together delimiting two separate passages, namely a central passage communicating both with the source of gaseous comburrent agent and with the liquid fuel source, and a peripheral passage communicating solely with the source of gaseous comburrent agent.
  • the prevaporisation device of the invention comprises, arranged inside said peripheral passage, at least within a zone of said passage which is located along the transverse portion of said arm, at least one vane or blade extending in a direction which has a component parallel to the general direction of said peripheral passage.
  • the external wall which delimits the peripheral channel aforementioned is pierced, at least in the zone of said channel located along said arm, by a plurality of sweat-pores through which a fraction of the flow of gaseous comburrent agent passing through said peripheral passage, can escape into the combustion chamber.
  • the peripheral passage in all situations, passes a cooling gas flow which makes it possible to dissipate towards the combustion chamber the heat absorbed by the hollow structure.
  • the function of the blades or vanes is to promote the transfer of said heat to the peripheral gas flow.
  • FIG. 1 is an axial half-section through a combustion system equipped with fuel prevaporisation devices
  • FIG. 2 is a view in partial transverse section, on the line II-II of FIG. 1, of said system;
  • FIG. 3 is a view on a larger scale, in section on the line III--III of FIG. 2, of a fuel prevaporisation device of known kind;
  • FIG. 4 is a view similar to that of FIG. 3, showing an improved prevaporisation device in accordance with the invention.
  • FIG. 5 is a sectional view, taken on the line VV, of part of the prevaporisation device shown in FIG. 4.
  • the general reference 7 has been utilised to designate liquid fuel prevaporisation devices fitted to a combustion system forming part, for example, of a gas turbine engine such as turbojet engine.
  • This installation which is of the kind known per se, comprises for example, a combustion chamber of axial X'X, delimited by an external casing la and an internal casing lb which are substantially coaxial with one another.
  • These two casings together define an annular space within which two walls 2a-2b, disposed substantially coaxially vis-a-vis the two casings, delimit an annular flame tube constituting the combustion space proper.
  • This latter is closed off at its upstream end, by an annular wall 3 or dome, inside which there is disposed an annular supporting structure 4.
  • the dome 3 and the annular structure 4 are pierced by holes 5-6 distributed uniformly about the axis X'-X of the chamber, each hole 6 being arranged in extension of a hole 5.
  • a prevaporisation device 7 is assembled with a certain clearance, on the axis of each of the holes 6.
  • the combustion chamber is connected at its upstream end to a source of comburrent agent such as compressed air, schematically represented by a line 8.
  • a source of comburrent agent such as compressed air, schematically represented by a line 8.
  • This air circulates through the annular spaces defined respectively between the casing la and the wall 2a, and the casing lb and the wall 2b, and enters the combustion space in the formof primary air, through the holes 5, and in the form of secondary air for cooling and dilution purposes, through holes 9a-9b, Illa-10b and Ila-1 lb.
  • the reference signifies a source of liquid fuel.
  • Each prevaporisation device 7 comprises (see also FIG. 3) a hollow structure projecting into the combustion chamber from a hole 6.
  • This hollow structure comprises a tubular body 12 coaxial with the hole 6, and two arms 13, 14 fixed to said body, the assembly of the body and the two arms presenting the appearanceof a generally T-shaped cane or the like.
  • the body 12 has an entry portion 12x communicating with the source 8 of gaseous comburrent agent, into which there also opens an injector 17 supplied with liquid fuel from the source 20.
  • Each of the arms 13, 14 has a portion 13x, 14x standing transversely to the general direction of the body 12, and an exit portion 13y, 14y which opens into the combustion chamber and through which, in operation, there is discharged a mixture of gaseous comburrent agent and at least partially vaporised fuel. It will be observed that each of the arms 13, 14 is bent so that its exit portion 13y, 14y extends in a direction having a component parallel to the general direction of the body 12.
  • the hole 6 has a larger cross-section than that of the body 12 in order to enable the assembly, around said body, of a sleeve 18 which may possibly be integral with said body.
  • Said sleeve in cooperation with the body 12, delimits an annular passage 19 through which direct admission into the combustion space, of a certain fraction of the primary airflow, takes place.
  • the major fraction (marked by the reference A) of the primary air flow enters, at the same time as the liquid fuel (marked by the reference C), the hollow structure or cane 7, the walls of which, at their internal surfaces, are subjected to the action of the flame so that the fuel vaporises.
  • the mixture of primary air and vaporised fuel (marked AC) if discharged substantially axially through the exit portions 13y, 14y of the arms 13, 14, in the reverse direction to the general direction of the flow of combustion gases, which general direction has been indicated in FIG. 1 by the arrow G.
  • the smaller fraction (marked by the reference a) of the air flow entering at 19 around the body 12, serves primarily to ensure a certain degree of thermal insulation of the upstream portion of the body 12 of the hollow structure 7.
  • the orifices 9a-9b make it possible to produce two groups of secondary air jets Fa-Fb which are substantially radially and mutually oppositely directed. These jets meet one another in the neighbourhood of the exit portions 13y, 14y of the arms l3, 14. Part of their flow then recirculates towards the upstream part of the chamber in order to produce, in the region adjacent the dome 3, a turbulent zone which promotes ignition and maintenance of combustion, whilst the other part of the flow passes directly downstream in the direction of the arrow G, for example towards an expansion turbine which has not been shown.
  • FIGS. 4 and 5 illustrate an example of a modified prevaporisation device in accordance with the inven tion, the modification being designed to reduce the risk of overheating referred to just now.
  • This device designated by the general reference 107, comprises a hollow, bent, T-shaped structure, designed to project into the combustion chamber.
  • the hollow structure 107 comprises a body 112 and one or more arms 113, 114.
  • the body 112 has an entry portion 112x communicating with the source of gaseous comburrent agent, and into which there opens a liquid fuel injector 1l7.
  • Each of the arms 113, 114 has a por tion 113x, 114x, extending transversely of the general direction of the body 112, and an exit portion ll3y, 114y which opens into the combustion chamber and through which, in operation, there is discharged a mixture AC of gaseous comburrent agent and at least partially vaporised fuel.
  • the exit portion 113y, 1l4y is preferably orientated in a direction having a component parallel to the general direction of the body 112.
  • the hollow structure 107 comprises at least in a zone which incorporates the transverse part 113x, 114x of the arm 113, 114 as well as a portion of the body 112, located near said transverse part, a double-walled system constituted by an internal wall S and an external wall T, together delimiting two separate passages, namely a central passage K, and a peripheral passage K
  • the two passages K, and K communicate with the source of gaseous comburrent agent, but only the central passage K, is supplied with liquid fuel through the injector 117.
  • One or more blades or vanes are arranged inside the peripheral passage K at least in a zone thereof situated along the transverse portion 113x, 114x of the arm 113, 114.
  • each of the blades or vanes 125 is in contact with the internal S and external T walls which delimit the peripheral passage K and extends in a direction having a component parallel to the general direction of said peripheral passage. This latter is thus sub-divided into at least two elementary passages K K through which there flow in parallel respective elementary flows of the gaseous comburrent agent.
  • the external wall T which delimits the peripheral passage K is pierced, at least in a zone of said passage disposed along the arm 113, 114 by a plurality of sweatpores 126 through which a fraction of the gaseous comburrent agent flow passing through said peripheral passage, can escape into the combustion chamber.
  • a sleeve 118 can furthermore be arranged around the external wall T of the body 112 of the hollow structure, in a zone which comprises at least the entry portion 112x of said body.
  • Said sleeve 118 and the external wall T thus together delimit a supplementary passage 119 having an entry end 119x comm unicating with the source of gaseous comburrent agent, and an exit end ll9y opening into the combustion chamber.
  • the prevaporisation device 107 passes three coaxial flows of gaseous comburrent agent, namely a central flow A, passing through the central passage K,, a peripheral flow A passing through the peripheral passage K and a supplementary flow a" passing through the supplementary passage 119. Only the central flow A, contains fuel.
  • vent holes 126 furthermore ensure the develop ment, in the neighbourhood of the external wall of the hollow structure, of a protective film of gaseous comburrent agent.
  • Another protective film is produced by the supplementary flow a" of gaseous comburrent agent, escaping from the supplementary passage 119.
  • a device for prevaporising liquid fuel designed for fitting to a combustion system comprising a combustion chamber, a source of liquid fuel and a source of gaseous comburrent agent, said device being of the kind which comprises, projecting into the combustion chamber, a hollow structure incorporating a body and at least one arm attached to said body and having at least one portion extending transversely of the general direction of said body, the latter comprising an entry portion which communicates with said sources of liquid fuel and gaseous comburrent agent, and said arm having an exit portion which opens into the combustion chamber and through which, in operation, there is discharged a mixture of gaseous comburrent agent and at least partially vaporised fuel, in which said hollow structure comprises, in a zone which incorporates the transverse portion of said arm, a double-walled system comprising an internal wall and an external wall which together delimit two separate passages, namely a central passage communicating both with the source of gaseous comburrent agent and with the liquid fuel source, and a peripheral passage communicating solely with the source of
  • a device for prevaporizing liquid fueld adapted to be fitted to a combustion system comprising a combustion chamber, a source of liquid fueld and a source of gaseous comburrent agent, said device comprising, projecting into the combustion chamber, a hollow structure incorporating a body and at least one arm attached to said body and having at least one portion extending transversely of the general direction of said body, said body comprising an entry portion which communicates with said sources of liquid fuel and gaseous comburrent agent, and said arm having an exit portion which opens into the combustion chamber and through which, in operation, there is discharged a mixture of gaseous comburrent agent and at least partially vaporized fuel, in which said hollow structure comprises, in a zone which incorporates the transverse portion of said arm, a double-walled system comprising an internal wall and an external wall which together delimit two separate passages, namely a central passage communicating both with the source of gaseous comburrent agent and with the liquid fueld source, and a peripheral passage communicating solely with the source of

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Spray-Type Burners (AREA)
US372514A 1972-06-23 1973-06-22 Devices for prevaporising liquid fuel Expired - Lifetime US3869865A (en)

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FR7222811A FR2189630B1 (enrdf_load_stackoverflow) 1972-06-23 1972-06-23

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US (1) US3869865A (enrdf_load_stackoverflow)
DE (1) DE2331723A1 (enrdf_load_stackoverflow)
FR (1) FR2189630B1 (enrdf_load_stackoverflow)
GB (1) GB1427540A (enrdf_load_stackoverflow)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4018554A (en) * 1975-03-19 1977-04-19 Institutul Pentru Creatie Stintifica Si Tehnica-Increst Method of and apparatus for the combustion of liquid fuels
US4070826A (en) * 1975-12-24 1978-01-31 General Electric Company Low pressure fuel injection system
US4735044A (en) * 1980-11-25 1988-04-05 General Electric Company Dual fuel path stem for a gas turbine engine
US4838029A (en) * 1986-09-10 1989-06-13 The United States Of America As Represented By The Secretary Of The Air Force Externally vaporizing system for turbine combustor
US5133192A (en) * 1989-08-31 1992-07-28 Rolls-Royce Plc Fuel vaporizer
US5377483A (en) * 1993-07-07 1995-01-03 Mowill; R. Jan Process for single stage premixed constant fuel/air ratio combustion
US5572862A (en) * 1993-07-07 1996-11-12 Mowill Rolf Jan Convectively cooled, single stage, fully premixed fuel/air combustor for gas turbine engine modules
US5613357A (en) * 1993-07-07 1997-03-25 Mowill; R. Jan Star-shaped single stage low emission combustor system
US5628182A (en) * 1993-07-07 1997-05-13 Mowill; R. Jan Star combustor with dilution ports in can portions
US5638674A (en) * 1993-07-07 1997-06-17 Mowill; R. Jan Convectively cooled, single stage, fully premixed controllable fuel/air combustor with tangential admission
US5924276A (en) * 1996-07-17 1999-07-20 Mowill; R. Jan Premixer with dilution air bypass valve assembly
US6220034B1 (en) 1993-07-07 2001-04-24 R. Jan Mowill Convectively cooled, single stage, fully premixed controllable fuel/air combustor
RU2179256C2 (ru) * 1999-06-21 2002-02-10 Открытое акционерное общество Самарский научно-технический комплекс им. Н.Д. Кузнецова Газогенератор жрд
US6925809B2 (en) 1999-02-26 2005-08-09 R. Jan Mowill Gas turbine engine fuel/air premixers with variable geometry exit and method for controlling exit velocities
CN105716120A (zh) * 2016-02-22 2016-06-29 中国科学院工程热物理研究所 一种燃油冷却式蒸发管结构
US20230184438A1 (en) * 2019-10-08 2023-06-15 Safran Helicopter Engines Pre-vaporisation tube for a turbine engine combustion chamber

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2524319C2 (de) * 1975-06-02 1984-03-08 Société Nationale d'Etude et de Construction de Moteurs d'Aviation, 75015 Paris Brennkammer mit einem abgestuften Flammmrohr
GB2215029B (en) * 1988-02-06 1991-10-09 Rolls Royce Plc Gas turbine engine fuel burner
US5156002A (en) * 1990-03-05 1992-10-20 Rolf J. Mowill Low emissions gas turbine combustor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1995934A (en) * 1933-09-18 1935-03-26 Trust Company Gas burner
US2780061A (en) * 1953-05-08 1957-02-05 Lucas Industries Ltd Liquid fuel burner for a combustion chamber provided with a surrounding air jacket
US2926495A (en) * 1955-12-29 1960-03-01 Gen Electric Fuel injection nozzle
US3540216A (en) * 1967-01-23 1970-11-17 Snecma Two-flow gas turbine jet engine
US3626444A (en) * 1968-11-04 1971-12-07 Snecma Improvements in liquid fuel vaporizing combustion systems

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1995934A (en) * 1933-09-18 1935-03-26 Trust Company Gas burner
US2780061A (en) * 1953-05-08 1957-02-05 Lucas Industries Ltd Liquid fuel burner for a combustion chamber provided with a surrounding air jacket
US2926495A (en) * 1955-12-29 1960-03-01 Gen Electric Fuel injection nozzle
US3540216A (en) * 1967-01-23 1970-11-17 Snecma Two-flow gas turbine jet engine
US3626444A (en) * 1968-11-04 1971-12-07 Snecma Improvements in liquid fuel vaporizing combustion systems

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4018554A (en) * 1975-03-19 1977-04-19 Institutul Pentru Creatie Stintifica Si Tehnica-Increst Method of and apparatus for the combustion of liquid fuels
US4070826A (en) * 1975-12-24 1978-01-31 General Electric Company Low pressure fuel injection system
US4735044A (en) * 1980-11-25 1988-04-05 General Electric Company Dual fuel path stem for a gas turbine engine
US4838029A (en) * 1986-09-10 1989-06-13 The United States Of America As Represented By The Secretary Of The Air Force Externally vaporizing system for turbine combustor
US5133192A (en) * 1989-08-31 1992-07-28 Rolls-Royce Plc Fuel vaporizer
US5628182A (en) * 1993-07-07 1997-05-13 Mowill; R. Jan Star combustor with dilution ports in can portions
US5765363A (en) * 1993-07-07 1998-06-16 Mowill; R. Jan Convectively cooled, single stage, fully premixed controllable fuel/air combustor with tangential admission
US5481866A (en) * 1993-07-07 1996-01-09 Mowill; R. Jan Single stage premixed constant fuel/air ratio combustor
US5572862A (en) * 1993-07-07 1996-11-12 Mowill Rolf Jan Convectively cooled, single stage, fully premixed fuel/air combustor for gas turbine engine modules
US5613357A (en) * 1993-07-07 1997-03-25 Mowill; R. Jan Star-shaped single stage low emission combustor system
US5377483A (en) * 1993-07-07 1995-01-03 Mowill; R. Jan Process for single stage premixed constant fuel/air ratio combustion
US5638674A (en) * 1993-07-07 1997-06-17 Mowill; R. Jan Convectively cooled, single stage, fully premixed controllable fuel/air combustor with tangential admission
US5477671A (en) * 1993-07-07 1995-12-26 Mowill; R. Jan Single stage premixed constant fuel/air ratio combustor
US6220034B1 (en) 1993-07-07 2001-04-24 R. Jan Mowill Convectively cooled, single stage, fully premixed controllable fuel/air combustor
US5924276A (en) * 1996-07-17 1999-07-20 Mowill; R. Jan Premixer with dilution air bypass valve assembly
US6925809B2 (en) 1999-02-26 2005-08-09 R. Jan Mowill Gas turbine engine fuel/air premixers with variable geometry exit and method for controlling exit velocities
RU2179256C2 (ru) * 1999-06-21 2002-02-10 Открытое акционерное общество Самарский научно-технический комплекс им. Н.Д. Кузнецова Газогенератор жрд
CN105716120A (zh) * 2016-02-22 2016-06-29 中国科学院工程热物理研究所 一种燃油冷却式蒸发管结构
US20230184438A1 (en) * 2019-10-08 2023-06-15 Safran Helicopter Engines Pre-vaporisation tube for a turbine engine combustion chamber
US11841140B2 (en) * 2019-10-08 2023-12-12 Safran Helicopter Engines Pre-vaporization tube for a turbine engine combustion chamber

Also Published As

Publication number Publication date
FR2189630A1 (enrdf_load_stackoverflow) 1974-01-25
FR2189630B1 (enrdf_load_stackoverflow) 1980-03-14
GB1427540A (en) 1976-03-10
DE2331723A1 (de) 1974-01-10

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