Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3577878 A
Publication typeGrant
Publication dateMay 11, 1971
Filing dateDec 11, 1968
Priority dateNov 10, 1967
Publication numberUS 3577878 A, US 3577878A, US-A-3577878, US3577878 A, US3577878A
InventorsKenneth Greenwood, Alban Heaton, Alwin Harrison, Squire Ronald Jackson
Original AssigneeLucas Industries Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Flame tubes for gas turbine engines
US 3577878 A
Images(18)
Previous page
Next page
Description  (OCR text may contain errors)

United'States Patent Inventors Kenneth Greenwood Burnley;

Alban Heaton, Gt. Harwood, near Blackburn; Alwin Harrison; Squire Ronald Jackson, Burnley, England Dec. 11, 1968 May 1 1, 1971 Joseph Lucas (Industries) Limited Birmingham, England App]. No. Filed Patented Assignee FLAME TUBES FOR GAS TURBINE ENGINES 5 Claims, 26 Drawing Figs.

US. Cl 60/39.65, 60/3923, 60/3929 Int. Cl F02c 9/14 Field of Search 60/3965,

[56] References Cited UNITED STATES PATENTS 2,446,059 7/1948 Peterson et a1. 60/39.65X 2,457,157 12/1948 King 60/3923 2,618,120 11/1952 Papini 60/39.65X 2,684,573 7/ 1954 Marskell et a1. 60/3923 2,812,637 11/1957 Fox 60/39.23X 2,837,894 6/1958 Kind 60/3927 3,078,672 2/1963 Meurer 60/39.65X

, FOREIGN PATENTS 539,069 8/ 1941 Great Britain 60/3965 Primary Examiner-Douglas Hart Attorney-Holman, Glascock, Downing and Seebold ABSTRACT: A flame tube for a gas turbine engine includes a plurality of primary combustion air inlets, a plurality of secondary combustion air inlets and a plurality of dilution air inlets and variable flow restricting means associated with at least some of the inlets for varying the ratio of primary combustion air to secondary combustion air to dilution air.

Patentd -May 11, 1971 I 3,577,878

18 Sheets-Sheet 1 FIG].

I 34 \{R INVENTOE' MM #0411477 M 7%; flaw/m ATTORNEY Paten ted May 11, 1971 3,577,878

18. Sheets-Sheet 2 INVENTOE M MM ham/m mm gag, [21416 /M7m ATTORNEY Patenid May 11, 1971 3,577,878

l8 Sheets-Sheet 5 FIGS.

INVENTOE flux/(W77, MM A ak, 1470 mm find/Mm ATTORNEY Patented May 1 1, 1971 18 Sheets-Sheet 4 FIGS.

INVENTOR- um In,

Patented May 11, 1971 3,577,878

18 Sheets-Sheet 5 Y INVENTOE Mm #mlmm/ ATTORNEY Patented May 11,1971- 3,577,878

18 Sheets-Sheet 7 INVENTO? :IIMJ M, 7/77., M7747, Mm flak/Wm ATTORNEY Patentd May 11, 1971 4 3,577,878

18 Sheets-Sheet 8 F! G. IO.

\ I I INVENTOE ATTORNEY Patented May 11, 1971 3,577,878

18 Sheen-Shoat 9 FIG. 1 l.

7 lNVENTOE I an. m,

- ATTORNEY Patented f May ll, 1971 1 3,577,878

18 Sheets-Sheet 10 I v F IG. I3.

. :m I I INVENTOE M 44444 AMMMMM $213 nut/d ATTORNEY Patcntied May 11, 1971 3 3,577,878

18 Shanta-Sheet u 1! JA- 'J "7'" Q 0 II. Q E 8 9. QQ'K Q MENTOR 7/7a,77 m,%mm 47 M m ATTORNEY Patented May 11, 1971 18 Sheets-Sheet 12 I 4 [K I YT i I) i i Q I U (O Q 0K 1 (U Q I7\ I O "'1 I 1 Q Q I LL- INVENTOE M 44; MMMMM 7%,, 4 774,

ATTORNEY Patented May 11, 1971 3,577,878

18 Sheets-Sheet; 13

FIG. l9.

' INVENTOE MM A M i/M m true Mam ATTORNEY 18 Sheets-Sheet 1s INVENTOE M Ma, x/mzz 7W ta Wm ATTORNEY 18 Sheets-Sheet 17 I INVENTOE M MM mmmmm flaw Mm ATTORNEY Patented May 11, 1971 3,577,878

18 Sheets-Sheet 18 \IIIIIIIIIIIIIIIIII -INVENTOE MW,%//m,%mm/flnw/ m ATTORNEY FLAME TUBES FOR GAS TURBINE ENGINES BACKGROUND OF THE INVENTION This invention relates to flame tubes for gas turbine engines.

In the flame tubes of such engines, it is the practice for a minor amount of air, about 2540 percent of the total air intake, to be employed for .the combustion of fuel, with the remainder being employed for cooling the flame tube, diluting of the flame and of the products of combustion before the latter are allowed to enter the turbine stage of the engine. The air for combustion purposes is itself normally separated into primary and secondary streams entering along separate paths to the interior of the flame tube. In some engines which are required to operate over a wide range of fuel/air ratios, the combustion and dilution air quantities over some parts of the operating range are incorrect thus impairing combustion and dilution air quantities over some parts of the operating range are incorrect thus impairing combustion efficiency and giving rise to loss of performance over that part of the engine operatmg range.

The object of the invention is to provide a flame tube for a gas turbine engine in which this disadvantage is overcome or reduced.

In accordance with the invention there is provided a flame tube for a gas turbine engine having a plurality of primary combustion air inlets, a plurality of secondary combustion air inlets, a plurality of dilution air inlets and variable airflow restricting means associated with at least some of said inlets for varying the ratio of primary combustion air to secondary combustion air to dilution air. Reference is now made to the accompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial section through an annular flame tube incorporating one example of the present invention,

FIG. 2 is a view on the arrow X in FIG. I,

FIG. 3 is a fragmentary view on the arrow Y in FIG. 2,

FIG. 4 is a pneumatic circuit diagram illustrating the manner in which the arrangement shown in FIGS. I, 2, 3 is operated,

FIG. 5 is a section through an annular flame tube illustrating another embodiment of the present invention,

FIG. 6 is a fragmentary front view of the arrangement shown in FIG. 5,

FIG. 7 is a fragmentary sectionlike FIG. 5 showing another example of the invention,

FIG. 8 is a view on the arrow 8 in FIG. 7,

FIG. 9 is another sectional view through an annular flame tube showing yet another embodiment of the invention,

FIG. 10 is a similar section showing a further embodiment of the invention,

FIG. 11 is a fragmentary sectional view showing yet a further embodiment of the invention,

FIG. 12 is a view on the arrow 12 in FIG. 11,

FIG. 13 is a section of another annular flame tube incorporating yet a further embodiment of the invention,

FIG. I4 is a section on line 14-14 in FIG. 13,

FIG. 15 is a section like FIG. 13 showing yet another embodiment of the invention.

FIG. 16 is a section on line 16-16 in FIG. 15,

FIG. 17 is a sectional view illustrating a still further embodiment of the invention,

FIG. 13 is a section of a primary combustion air inlet variable flow restrictor,

FIG. 19 is a view on arrow X in FIG. 18; and

FIGS. 20 to 26 are views showing alternative forms of primary combustion air inlet variable flow restrictors.

DETAILED DESCRIPTION OF THE INVENTION Referring firstly to the embodiment shown in FIGS. 1 to 4 of the drawings, the flame tube incorporates an inner annular passage 30 for the primary combustion air, a surrounding annular passage 31 for secondary combustion air and an outer annular passage 32 for the dilution air. The passage 30 has an annular intake 33 whereas the passage 31 has a pair of annular intakes 34, 35 disposed respectively inside and outside the intake 33. A row of vanes 36 are mounted in the intake 33 and rows of vanes 37, 38 are likewise mounted in the intakes 34, 35 respectively. The vanes 36, 37 and 38 are on a series of common shafts arranged so that when the vanes 36 lie in planes parallel to the axis of the engine, the vanes 37, 38 are offset and vice versa. Thus when positioned as shown in full lines in FIG. 2 the primary combustion airflow will be restricted while the secondary combustion airflow will be substantially unrestricted.

The vanes, are, however, associated with pneumatic actuators 39 associated with pipework 40, 41 whereby the vanes can be turned to the positions shown in dotted lines in FIG. 2 such that the vanes 36 scarcely restrict airflow into the intake 33 whereas the vanes 37, 38 restrict airflow into the intakes 34, 35. As will be seen from FIG. 3.the actuators 39 are arranged to turn alternate ones of the shafts on which the vanes are mounted in one direction and the remaining shafts in the opposite direction so that no swirl is introduced either into the primary combustion air or secondary combustion air.

FIG. 4 shows how a single valve 42 can be employed to control the supply of compressed air to the pipework 40, 41 and the exhausting of air therefrom to enable all the vanes 36, 37, 38 to be adjusted simultaneously.

Turning now to FIGS. 5 and 6, the flame tube has a series of primary air inlets 50 each provided with swirler vanes which are known per se. Secondary combustion air is introduced via inwardly directed nozzles 51, of which there are two in association with each of the primary air inlets. Dilution air is introduced at two stages in the flame tube, mainly through a first series of nozzles 52 downstream of the nozzles 51 and through a second series of nozzles 53 downstream of the nozzles 52. The nozzles 53 are supplied via ducts 54 which open into intakes upstream of the nozzles 51. The flame tube si provided with axially movable deflector vanes 55 which can be moved from the positions shown in FIG. 5 in which they cover the intakes to the ducts 54, to positions in which they cover intakes to the secondary combustion air nozzles 51.

Referring now to the examples shown in FIGS. 7 and 8, the basic layout of the flame tube is similar to that shown in FIG. I, that is to say there is an annular primary air duct 60 surrounded externally by a III'SI secondary air duct 61 and internally by a second annular secondary air duct 62. There are also dilution air passages 63, 64 respectively outside the duct 61 and inside the duct 62.

For controlling the proportions of primary and secondary air there are provided three annular flow restricting members 65, 66, and 67. These three restrictors are joined together by means of radial arms 68 so as to be movable axially relative to the flame tube by means of rods like the rod 69. At one limit of the travel, as shown in FIG. 7 the annular restrictors 65, 66

restrict the entry of secondary combustion air to the ducts 61, i

62 respectively. In this position the restrictor 67 is deep inside the duct 60 and provides little restriction of the airflow therethrough. It will be noted, however, that the duct 60 diverges markedly from its intake so that when the restrictors are moved the their other position (as shown in dotted lines in FIG. 7) the restrictor 67 will provide a considerable restriction in the intake of the duct 60, whereas the restrictors 65, 66 will have little effect on the airflow into the ducts 61., 62 respectively.

In the example shown in FIG. 9 the secondary air intake is defined by an outer tube 70 and an inner tube 71. The outer tube 70 lies outside an inner tube 72 forming the outer wall of the primary air duct the inner wall 73 of which is outside the tube 71. The primary/secondary combustion air proportions are varied by means of a pair of annular rows of flaps 74, 75. These flaps are pivoted on tangential axes and when, as shown in FIG. 9 the outer row of flaps 74 are pivoted inwardly and the inner row of flaps 75 are pivoted outwardly there is a minimum area for primary airflow and a maximum area for

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2446059 *Oct 5, 1944Jul 27, 1948Peabody Engineering CorpGas heater
US2457157 *Jul 30, 1946Dec 28, 1948Westinghouse Electric CorpTurbine apparatus
US2618120 *Jun 7, 1946Nov 18, 1952Papini AnthonyCoaxial combustion products generator and turbine with cooling means
US2684573 *Dec 9, 1950Jul 27, 1954Babcock & Wilcox CoMeans for regulating gaseous fluid flow to combustion apparatus
US2812637 *Dec 21, 1951Nov 12, 1957Phillips Petroleum CoFuel air ratio regulation for combustion systems
US2837894 *Dec 5, 1955Jun 10, 1958Bbc Brown Boveri & CieAutomatic air regulating device in combustion chambers of gas turbine plants
US3078672 *Mar 22, 1960Feb 26, 1963Maschf Augsburg Nuernberg AgProcess and apparatus for operating a continuous or intermittent combustion engine
GB539069A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3742702 *Jan 22, 1971Jul 3, 1973Gen Motors CorpRegenerative gas turbine system
US3765171 *Mar 11, 1971Oct 16, 1973Mtu Muenchen GmbhCombustion chamber for gas turbine engines
US3899881 *Feb 4, 1974Aug 19, 1975Gen Motors CorpCombustion apparatus with secondary air to vaporization chamber and concurrent variance of secondary air and dilution air in a reverse sense
US3927520 *Feb 4, 1974Dec 23, 1975Gen Motors CorpCombustion apparatus with combustion and dilution air modulating means
US3930368 *Dec 12, 1974Jan 6, 1976General Motors CorporationCombustion liner air valve
US3930369 *Feb 4, 1974Jan 6, 1976General Motors CorporationLean prechamber outflow combustor with two sets of primary air entrances
US4054028 *Aug 28, 1975Oct 18, 1977Mitsubishi Jukogyo Kabushiki KaishaFuel combustion apparatus
US4078377 *Jan 28, 1974Mar 14, 1978Ford Motor CompanyInternally vaporizing low emission combustor
US4090360 *May 12, 1976May 23, 1978Bbc Brown Boveri & Company LimitedSingle chamber type combustion structure for a gas turbine engine
US4150539 *Jul 20, 1977Apr 24, 1979Avco CorporationLow pollution combustor
US4171612 *Jun 6, 1977Oct 23, 1979Zwick Eugene BLow emission burner construction
US4255927 *Jun 29, 1978Mar 17, 1981General Electric CompanyCombustion control system
US4380895 *Jun 15, 1981Apr 26, 1983Rolls-Royce LimitedCombustion chamber for a gas turbine engine having a variable rate diffuser upstream of air inlet means
US4446692 *Jul 31, 1979May 8, 1984Rolls-Royce LimitedFluidic control of airflow in combustion chambers
US4563875 *Mar 21, 1985Jan 14, 1986Howald Werner EFor generating a hot gas stream
US4586328 *May 11, 1982May 6, 1986Howald Werner ECombustion apparatus including an air-fuel premixing chamber
US5351474 *Apr 16, 1993Oct 4, 1994General Electric CompanyCombustor external air staging device
US5398495 *Apr 15, 1994Mar 21, 1995Societe Nationale D'etude Et De Construction De Moteurs D'aviation (S.N.E.C.M.A.)Combustion chamber with variable oxidizer intakes
US5829244 *May 9, 1997Nov 3, 1998Societe Natiional D'etude Et De Construction De Moteurs D'aviation (S.N.E.C.M.A.)Fuel pressure actuated air control for a combustion chamber burner
US6425240Jun 13, 2000Jul 30, 2002Abb Alstom Power Uk Ltd.Combustor for gas turbine engine
US7024862 *May 30, 2003Apr 11, 2006Mitsubishi Heavy Industries, Ltd.System and method for controlling combustion in gas turbine with annular combustor
EP1063476A1 *Jun 19, 2000Dec 27, 2000ABB Alstom Power UK Ltd.Combustor for gas turbine engine
Classifications
U.S. Classification60/39.23, 60/794, 60/759
International ClassificationF23R3/26
Cooperative ClassificationF05B2250/411, F23R3/26, F05B2260/70, F23R2900/00001
European ClassificationF23R3/26