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 numberUS3777983 A
Publication typeGrant
Publication dateDec 11, 1973
Filing dateDec 16, 1971
Priority dateDec 16, 1971
Also published asDE2261038A1, DE2261038C2
Publication numberUS 3777983 A, US 3777983A, US-A-3777983, US3777983 A, US3777983A
InventorsHibbins W
Original AssigneeGen Electric
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Gas cooled dual fuel air atomized fuel nozzle
US 3777983 A
Abstract
A dual fuel, air-atomized, fuel nozzle of the type prevalent in some gas turbine combustion chambers wherein the hot atomizing air conduit is remotely positioned with respect to a central liquid fuel or oil conduit so that the nozzle will operate cooler during liquid fuel operation. A gaseous fuel conduit is interposed between the liquid fuel conduit and the atomizing air conduit to provide additional nozzle cooling during the gaseous fuel operation while preventing thermal breakdown of any liquid fuel residuum which could cause nozzle clogging.
Images(1)
Previous page
Next page
Description  (OCR text may contain errors)

[45] Dec. 11, 1973 Mnited States Patent Hibbins GAS COOLED DUAL FUEL AIR ATOMIZED FUEL NOZZLE BACKGROUND OF THE INVENTION This invention pertains in general to fuel nozzles of the type prevalent in gas turbine combustion chambers and in particular relates to dual fuel nozzles utilizing high-temperature atomizing air.

Liquid fuel which is to be utilized in a gas turbine combustion chamber must be atomized at the nozzle portion before proper combustion may take place. Atomizing the fuel consists in breaking down the fuel into kfine particles to form a spray at the nozzle portion.

There are generally two methods of atomizing fuel, i.e., pressure atomizing and air atomizing'Pressure atomizing comprises the sending of liquid fuel under high pressure through a greatly restricted orifice or nozzle. Air atomizing consists of striking liquid fuel with va high-temperature, high-pressure jet of air as the liquid fuel leaves the nozzle. This causes the liquid fuel to be broken down into particles and form a cone-shaped spray. Air-atomized nozzles have ecological advantages in that they reduce the amount of smoke present in the combustion process.

A dual fuel nozzle is one which may run on either gaseous fuel or liquid fuel. The criteria which determines which fuel is used may be based on economic considerations or supply considerations. In a dual fuel, air-atomized nozzle, high-temperature atomizing air is used in conjunction with the flow of liquid fuel. A problem arises when a transfer is made from liquid fuel to gaseous fuel in that a residuum of liquid fuel remains in the liquid fuel or oil passages of the nozzle and is subject to long periods of heat soaking which breaks down the oil into gums, carbon and varnish. One source of heat is the high-temperature atomizing air which usually runs adjacent and parallel to the liquid fuel passageway. The deposits of gums, carbon and varnish clog the small orifices in the nozzle and upon retransferring from gaseous to liquid fuels, the liquid fuel pressure becomes excessive and the flow restricted.

One method of attempting to reduce residuum bluidup, is by passing a reduced flow of atomizing air through the liquid fuel nozzle while running on gas This method has not been 4successful because the atomizing air passes over any nozzle clogs, not through them, and hence does not purge the oil from the system; also, the temperature of the atomizing air is such that it may induce thermal breakdown ofthe residuum of liquid fuel.

In a dual fuel, atomizing air fuel nozzle for a gas turbine combustion chamber, it is one object of this invention to prevent thermal breakdown of residuum liquid fuels and consequent nozzle clogs while the nozzle is running on gaseous fuel.

Another object of this invention is to lower the operating temperatures of the nozzle while the nozzle is running on liquid fuels.

Other objects and advantages will become apparent from the following description of the invention and the novel features will be particularly pointed out hereinafter in the claims.

SUMMARY OF THE INVENTION A dual fuel, air-atomized fuel nozzle including a nozzle support ring having concentric flange portions and a center opening. A liquid fuel or oil pipe is disposed into the center opening and engages a first flange portion. A nozzle cap is disposed about the oil pipe and engages a second flange portion while defining an annular gas plenum. A retaining ring is partially disposed over the nozzle cap and engages a third flange portion while defining an annular atomizing air plenum. The atomizing air plenum is remotely positioned from the liquid fuel pipe to prevent the atomizing air from heating the liquid fuel or liquid fuel residuum. The gas plenum provides additional nozzle cooling when the nozzle is operating on gaseous fuel and further acts to prevent thermal breakdown of residuum liquid fuel.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. l is an elevation view, partially in cross section. of a dual fuel, air-atomized nozzle with a swirler cap having the present invention applied thereto.

FIG. 2 is an elevation', partial cross section of a dual fuel, air-atomized nozzle with a shrouded nozzle cap having the present invention applied thereto.

DETAILED DESCRIPTION OF THE INVENTION `ring 15.

An air swirler nozzle cap 3l of the type disclosed in U. S. Patent Application Ser. No. 7,947, filed Feb. 2, 1970, for Edward P. Hopkins, now matured into U. S. Pat. No. 3,630,024, and assigned to the assignee of the present invention, is placed around the oil pipe casing 25. The swirler cap 3l has external threads which are secured into a second threaded flange portion 35 on the nozzle support ring 15. The swirler cap has a plurality of swirler blades 37 circumferentially arranged at the forward end of the swirler cap and having gas distribution holes 38 positioned between selected blades. A circumferential mounting ring 39 surrounds the swirler blades and positions a combustion chamber casing 40 and liner 4l.

An annular gas plenum 45 is defined by the nozzle support ring 15, the oil pipe casing 25 and the nozzle cap 3l. The gas plenum is fed through a plurality (only one shown) of circumferentially arranged inlet pipes 49 which are connected to an outside supply pipe. Gas is then distributed from the plenum through selected swirler blades by means of a plurality (only one shown) of gas passages 51 which are circumferentially arrayed within the gas nozzle, each terminating in a gas distribution hole 38.

A retaining ring 59 having an exterior threaded portion is secured into a third threaded flange portion 6l on the nozzle support ring 15 and is formed with an inwardly directed flange which abuts the swirler cap formed with a mating outwardly directed flange to form a seal 65.

An annular atomizing air plenum 7l is defined within the retaining ring 59, the nozzle cap 3l and the nozzle support ring 15. The plenum 7l is supplied by means of a plurality (only one shown) of circumferentially arranged inlet pipes 75 which are connected to an outside supply pipe. Atomizing air is delivered to the nozzle face through a plurality of air passages 79 (only one shown) into a distribution ring 80. The distribution ring 80 is an annulus adjacent the nozzle casing which feeds atomizing air to circumferentially arranged slots or openings 8l in the face of the casing 25 to distribute atomizing air to the fuel emanating from the fuel nozzle.

Referring now to FIG. 2, a second embodiment of a dual fuel atomized fuel nozzle lll is shown including a nozzle support ring 115. A centrally mounted oil supply pipe 119 is connected at one end to an oil supply source and terminates at the other end in an oil nozzle 121. The oil pipe is formed within a casing 125 having an exterior threaded portion. The threaded portion is secured within a first threaded flange portion 129 on the nozzle support ring.

A shrouded nozzle cap 131 is positioned about the front end of the oil pipe casing 125 and includes an exterior threaded portion which is secured within a second threaded flange portion 13S of the nozzle support ring. The outer portions of the shrouded nozzle cap contact a combustion chamber casing 140 and liner 141. The nozzle support ring, the oil pipe casing and the shrouded nozzle cap define an annular gas plenum 145. A plurality (only one shown) of circumferentially arranged inlet pipes 149 feed gaseous fuel from a supply pipe to the plenum which is distributed to the shrouded nozzle cap face through gas passages 151 and outlet holes 153 in the face of the nozzle cap. Both the gas passages and the outlet holes are circumferentially arranged about the nozzle cap.

A retaining ring 159 having an exterior threaded portion is secured into a third threaded flange portion 161 on the nozzle support ring 115 and is formed with an inwardly directed flange which abuts the nozzle cap 131 at an outwardly directed mating flange and holds it in place, as well as forming a seal 165.

An annular atomized air plenum 171 is defined within the retaining ring 159, the nozzle cap 131 and the nozzle support ring 115. The plenum 171 is supplied by means of a plurality (only one shown) of circumferentially arranged inlet pipes 175 which are connected to an outside supply pipe. Atomizing air is delivered to the nozzle face through a plurality of air passages 179 (only one shown) into a distribution ring 180. The distribution ring includes an annulus adjacent the nozzle casing 125 face which distributes atomizing air thereto through slots or openings 181 adjacent the fuel nozzle 121 opening.

OPERATION There are two modes of operation inherent in the operation of a dual fuel nozzle. The nozzle may operate on liquid fuels such as oil or it may operate on gaseous fuel. When the nozzle operates on liquid fuel, hot atomizing air is sent through the air passages so that oil flowing through the oil nozzle is atomized. The atomizing air is at a temperature of about 350F.

The nozzle may be switched to operate on gaseous fuel which is usually at a temperature of 70-90F. When the nozzle operates on gaseous fuel, the atomizing air passages carry a reduced amount of air and the oil pipe is shut off.

The problem arises when the nozzle is running on gaseous fuel in that a residuum of liquid fuel remains in the oil pipe and will break down into clogs of gum,

carbon and varnish if the hot atomizing air pipe is adjacent the oil pipe. By transposing the gas and atomizing air conduits as taught by the present invention, residuum oil clogs are prevented because the atomizing air conduit is farther away from and separated from the oil pipe by the gas plenum 45, and because the flow of relatively cool gaseous fuel cools the nozzle when the gaseous operation of the nozzle is in use.

A further benefit of the transportation of the gaseous and air atomizing pipes is that the nozzle itself will run cooler about l50F when operating on liquid fuel.

While there is shown what is considered to be, at present, the preferred embodiment of the invention, it is, of course, understood that various other modifications may be made therein and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.

What is claimed is:

l. A dual fuel, air-atomized fuel nozzle of the type used in a combustion chamber for a gas turbine, said nozzle including:

a nozzle support ring having concentric flange portions and a center opening;

a liquid fuel conduit partially disposed within said center opening and engaging a first concentric flange;

an annular nozzle cap partially disposed about said liquid fuel conduit and engaging a second concentric flange to define an annular gas plenum with said support ring and said liquid fuel conduit;

at least one gas supply pipe interconnecting said gas plenum with a gas supply through said nozzle support ring; and, gas passageways through said nozzle cap interconnecting the gas plenum with said combusion chamber; and,

an annular retaining ring abutting said nozzle cap and engaging a third concentric flange to define an annular atomizing air plenum with said support ring and said nozzle cap, whereby said liquid fuel conduit is insulated from said atomizing air plenum by said gas plenum, gas supply pipe and said gas passageways.

2. The nozzle as recited in claim 1 wherein the nozzle cap is formed with a plurality of circumferentially arrayed blades disposed within the combustion chamber and having holes between selected blades; the gas passages interconnecting thegas plenum with the holes between circumferentially arrayed blades.

3. The nozzle as recited in claim 1 wherein the nozzle cap is formed with a plurality of concentrically arrayed outlet holes communicating with the combustion chamber and through the face of the nozzle cap; the gas passageways interconnecting the gas plenum with said circumferentially arrayed holes.

4. The nozzle as recited in claim l further including a plurality of atomizing air inlet pipes passing through the nozzle support ring and interconnecting the atomizing air plenum with an atomizing air supply.

5. The nozzle as recited in claim 4 further including a plurality of atomizing air passageways interconnecting the atomizing air plenum with a distribution ring in communication with an oil nozzle within the liquid fuel conduit.

6. The nozzle as recited in claim l wherein the first, second and third concentric flanges are threaded for easy assembly and disassembly.

7. The nozzle as recited in claim 1 wherein said nozzle cap and retaining ring are formed with inwardly and outwardly directed flanges forming a seal.

lk k Ik lk

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1876610 *Feb 8, 1929Sep 13, 1932 Spray gun
US2907527 *Apr 10, 1956Oct 6, 1959Thompson Ramo Wooldridge IncNozzle
US3121996 *Oct 2, 1961Feb 25, 1964Lucas Industries LtdLiquid fuel combustion apparatus
US3285007 *Oct 26, 1964Nov 15, 1966Rolls RoyceFuel injector for a gas turbine engine
US3610537 *Jan 27, 1969Oct 5, 1971Daido OxygenLiquid fuel combustion device
US3630024 *Feb 2, 1970Dec 28, 1971Gen ElectricAir swirler for gas turbine combustor
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3886736 *Oct 31, 1973Jun 3, 1975Westinghouse Electric CorpCombustion apparatus for gas turbine
US3980417 *Nov 27, 1974Sep 14, 1976Afga-Gevaert N.V.Apparatus for incinerating non-halogenated waste liquids
US4036434 *Jul 15, 1974Jul 19, 1977Aerojet-General CorporationFluid delivery nozzle with fluid purged face
US4253301 *Oct 13, 1978Mar 3, 1981General Electric CompanyFuel injection staged sectoral combustor for burning low-BTU fuel gas
US4288980 *Jun 20, 1979Sep 15, 1981Brown Boveri Turbomachinery, Inc.Combustor for use with gas turbines
US4327547 *Nov 5, 1979May 4, 1982Rolls-Royce LimitedFuel injectors
US4337618 *May 23, 1980Jul 6, 1982Rolls-Royce LimitedGas turbine engine fuel burners
US4412808 *Jun 19, 1980Nov 1, 1983Trw Inc.Dual fueled burner gun
US4463568 *Jul 20, 1982Aug 7, 1984Rolls-Royce LimitedFuel injector for gas turbine engines
US4735044 *Nov 25, 1980Apr 5, 1988General Electric CompanyDual fuel path stem for a gas turbine engine
US4850194 *Dec 7, 1987Jul 25, 1989Bbc Brown Boveri AgBurner system
US4854127 *Jan 14, 1988Aug 8, 1989General Electric CompanyBimodal swirler injector for a gas turbine combustor
US4967561 *Oct 30, 1989Nov 6, 1990Asea Brown Boveri AgCombustion chamber of a gas turbine and method of operating it
US5203796 *Aug 28, 1990Apr 20, 1993General Electric CompanyTwo stage v-gutter fuel injection mixer
US5222357 *Jan 21, 1992Jun 29, 1993Westinghouse Electric Corp.Gas turbine dual fuel nozzle
US5351489 *Dec 23, 1992Oct 4, 1994Kabushiki Kaisha ToshibaFuel jetting nozzle assembly for use in gas turbine combustor
US5361578 *Dec 2, 1993Nov 8, 1994Westinghouse Electric CorporationGas turbine dual fuel nozzle assembly with steam injection capability
US6047926 *Jun 17, 1997Apr 11, 2000Alliedsignal Inc.Hybrid deicing system and method of operation
US6293498Feb 18, 2000Sep 25, 2001Honeywell International Inc.Hybrid deicing system and method of operation
US6360992Apr 10, 2000Mar 26, 2002Honeywell International Inc.Hybrid deicing system and method of operation
US6402059 *Feb 14, 2000Jun 11, 2002Alstom (Switzerland) LtdFuel lance for spraying liquid and/or gaseous fuels into a combustion chamber, and method of operating such a fuel lance
US6539724 *Mar 30, 2001Apr 1, 2003Delavan IncAirblast fuel atomization system
US6547163 *Sep 12, 2000Apr 15, 2003Parker-Hannifin CorporationHybrid atomizing fuel nozzle
US6945051 *Nov 8, 2002Sep 20, 2005Enel Produzione S.P.A.Low NOx emission diffusion flame combustor for gas turbines
US7082768 *Jun 18, 2004Aug 1, 2006Alstom Technology LtdMethod for injecting a fuel-air mixture into a combustion chamber
US7117678Apr 2, 2004Oct 10, 2006Pratt & Whitney Canada Corp.Fuel injector head
US7117679 *Aug 6, 2004Oct 10, 2006Rolls-Royce PlcFuel injection
US7406827Jun 27, 2006Aug 5, 2008Alstom Technology LtdApparatus for injecting a fuel-air mixture into a combustion chamber
US7431240Aug 17, 2000Oct 7, 2008Honeywell International Inc.Hybrid deicing system and method of operation
US7533532 *May 8, 2006May 19, 2009Rolls-Royce PlcFuel injection
US7536862 *Sep 1, 2005May 26, 2009General Electric CompanyFuel nozzle for gas turbine engines
US7934380 *Oct 26, 2007May 3, 2011Rolls-Royce Power Engineering PlcMethod and apparatus for isolating inactive fuel passages
US7992390 *Sep 23, 2008Aug 9, 2011Pratt & Whitney Canada Corp.External rigid fuel manifold
US8015815 *Apr 18, 2008Sep 13, 2011Parker-Hannifin CorporationFuel injector nozzles, with labyrinth grooves, for gas turbine engines
US8141363 *Oct 8, 2009Mar 27, 2012General Electric CompanyApparatus and method for cooling nozzles
US20110083442 *Oct 8, 2009Apr 14, 2011General Electric CompanyApparatus and method for cooling nozzles
US20110100015 *Nov 5, 2009May 5, 2011General Electric CompanyGas turbine system to inhibit coke formation and methods of use
US20130029032 *Sep 25, 2012Jan 31, 2013Optomec, Inc.Mechanically Integrated and Closely Coupled Print Head and Mist Source
EP2634490A1 *Feb 28, 2013Sep 4, 2013Hitachi Ltd.Gas turbine combustor
Classifications
U.S. Classification239/422, 239/406, 239/425, 60/742, 431/284
International ClassificationF23D11/10, F23R3/36, F23D17/00, F23R3/28, F23D11/12
Cooperative ClassificationF23D11/106, F23D11/10, F23D17/002
European ClassificationF23D11/10B, F23D11/10, F23D17/00B