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Publication numberUS3741484 A
Publication typeGrant
Publication dateJun 26, 1973
Filing dateSep 24, 1971
Priority dateSep 30, 1970
Publication numberUS 3741484 A, US 3741484A, US-A-3741484, US3741484 A, US3741484A
InventorsA Cresswell
Original AssigneeDecafix Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Atomisers
US 3741484 A
Abstract
Method and apparatus for atomising liquids in which a liquid is fed from an outer, annular, convergent nozzle into a stream of gas fed at sonic velocity from a coaxial inner convergent nozzle. A difergent deflector is positioned coaxially within the outlet openings of the two nozzles.
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Description  (OCR text may contain errors)

United States Patent 1191 Cresswell 5] June 26, 1973 [5 ATOMISERS 3,534,909 10/1970 Paine 239/424 x 978,860 12/1910 Dietz [75] Inventor. Alan Cresswell, Strood, England 1,075,742 10/1913 weimz [73] Assignee: Decatix Limited, Rochester, Kent, 1,793,897 2/1931 England 2,089,673 8/1937 Stemmann 2,917,386 12/1959 Jones et a]. 239/424 X [22] Filed: Sept. 24, 1971 3,009,826 11/1961 Straughn et a1 239/424 X 211 App]. No.: 183,585

Primary Examiner-Lloyd L. King Art All' C. C 11 d [30] Foreign Application Priority Data Qmey 0 at Sept. 30, 1970 Great Britain 46400/70 [57] ABSTRACT 52 U.S. l 24 3 Int 8 239/4 2 i i gg Method and apparatus for atomlsmg llqHldS in which a [58] Fieid 423 424 liquid is fed from an outer, annular, convergent nozzle 239/lo2 into a stream of gas fed at sonic velocity from a coaxial 1 inner convergent nozzle. A difergent deflector is posi- [56] References Cited tioned coaxially within the outlet openings of the two UNITED STATES PATENTS mules 1,002,594 9/1911 Mason et al. 239/424 X 8 Claims, 3 Drawing Figures PATENTEDJUHZB 1915 3,741,4

sum 1 or z FIG.

INVENTOR ALAN CRessweLL PAIENTEDJUNZS I975 3.741.484

sum 2 or 2 .2 b 5 I 160% I 140% m SUB. s0/v/cg SUPER. s0/v/c 5) 100 5;

I 80 m in Q Q- n SON/C Q U VELOCITY q FIG}.

INVENTOR Rum Ckessweu.

ATTORNEY ATOMISERS The invention relates to atomisers, for example for atomising fuel oil for burners such as may be used for firing water tube and packaged shell boilers or for atomising a liquid for use in gas cooling.

According to one aspect of the invention an atomiser comprises an outer, annular, convergent liquid nozzle chamber, a coaxial inner convergent gas nozzle chamber and a divergent deflector member positioned coaxially within outlet openings of the two chambers.

An inner surface of said gas nozzle chamber may be formed by a convergent surface of said deflector member. Preferably an outer surface of said gas nozzle chamber and an inner surface of said liquid nozzle chamber are formed by the respective inner and outer surfaces of a cylindrical portion of a distributor member for feeding both the liquid and gas to said chambers. An outer surface of said liquid nozzle chamber may comprise a convergent inner surface of an annular member carried by the distributor member. Conveniently the deflector member is screw-threadedly located with a screw-threaded central aperture in the distributor member and the annular member is screwthreadedly located with a screw-threaded outer portion of the distributor member.

The outlet of said liquid nozzle chamber may be bounded by a knife edge. The deflector member may diverge from where it extends from the outlet openings of the two chambers.

According to a further aspect of the invention an atomiser comprises a distributor member formed with an inner ring of gas passages, an outer ring of liquid passages and a cylindrical portion extending from one end between the two rings of passages, an annular member which screw-threadedly engages with the distributor member around the cylindrical portion to form a convergent liquid nozzle chamber therewith in communication with the ring of liquid passages and a deflector member which screw-threadedly engages with a central aperture in the distributor member so as to form a convergent gas nozzle chamber with said cylindrical portion in communication with the ring of gas passages.

According to yet a further aspect of the invention a method of atomising a liquid comprises feeding the liquid froma convergent nozzle together with a gas fed at sonic velocity so as to form a divergent nozzle with the radially inner surface of the nozzle being comprised by a divergent member, the radially outer surface of the nozzle being comprised by said liquid and the gas being fed therebetween.

The foregoing and further features of the invention may be more readily understood from the following description of two preferred embodiments thereof, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a side sectional view of an atomiser;

FIG. 2 is a perspective view, part cut away of an alternative atomiser, and

FIG. 3 is a diagrammatic representation, on enlarged scale of the nozzle outlets of the FIG. 2 atomiser together with a simplified graphical representation of the gas pressures along the axis of the atomiser during the actual expansion process.

Referring now to FIG. 1 of the drawing there is shown an atomiser which comprises a distributor member 11 formed with an outer circumferential ring of axial liquid feed passages 12 and an inner circumferential ring of axial gas feed passages 13. A feed pipe 14 is screw-threaded into a rearwardly extending flange 15 formed on distributor member 11. An outer feed pipe 16 is a press fit on the outer periphery of distributor member 11, is held in position by the screw-threaded engagement of pipe 14 with flange 15, and is sealed by an O-ring seal 17.

The feed passages 13 lead into a convergent annular nozzle chamber 13 which is defined by the inner frustoconical surface of an annular member 19 and the outer surface of a deflector member 20 which is screwthreaded into a central aperture at the front of distributor member [1. Metering apertures 21 are formed in the member 19 arranged to be in registry with the outer feed passages 12 in distributor member 11. An annular convergent liquid nozzle chamber 22 is defined by the forward surface of member 19 and the arcuate inner surface of an annular member 23 positioned coaxially with member 19 and having a rearwardly extending flange fitting around the outer periphery of distributor member 11 and abutting the O-ring seal 17. The arcuate inner surface of member 23 terminates at a knife edge 23a at a central opening in member 23.

The outer surface of deflector member 20 is formed to be convergent where it is within resonating chamber 22 and is also formed with a divergent deflecting surface 20a towards its outer end.

In operation, for example to atomise a fuel oil, air or some other gas is fed under pressure along inner feed pipe 14, passes through feed passages 13 to the convergent chamber 18. The arrangement of the chamber convergence and opening size and the pressure of the gas are such that a jet of such gas is emitted into chamber 22 at a pressure which is above the critical pressure ratio for the gas. The oil or other liquid to be atomised is fed through outer feed pipe 16, usually at a viscosity not exceeding seconds Redwood 1 scale, through feed passages 12 and metering apertures 21 into chamber 22. In chamber 22 the oil accelerates around the inner arcuate surface and leaves such arcuate surface at the knife edge 23a in a direction opposed to the pressure wave of compressible fluid emanating from the convergent chamber 18 at sonic velocity.

The surface of the oil at the knife edge 23a absorbs the energy of the vibrating air and at the same time the oil film near the knife edge is subjected to powerful shearing forces.

The oil then reverts to a minimum surface energy condition and forms very fine droplets. This condition is achieved without entrainment of the oil on to the metallic surfaces of the atomiser and is achieved by the convergent tapering of the deflector member 20 such that a high velocity cushion of air exists between oil film leaving knife edge 23a and the surface of deflector member 20. Further shearing is achieved by the shock waves produced in the air along the deflector member where the air decelerates from supersonic to subsonic velocity. The exit angle of the droplets is finally determined by the end diameter and divergence angle of deflector member 20.

Referring now to FIG. 2 there is shown an alternative form of atomiser which is similar to that of FIG. 1 but is simplified in that it comprises only three separate components; distributor member 11; annular member 23 and deflector member20. In this arrangement the liquid nozzle chamber 22 is formed by a cylindrical extension 11a of member 11 and annular member 23 which is formed with a frusto-conical inner surface 23b to provide the convergence of chamber 22. The inner gas nozzle chamber 18 is formed by the inner surface of extension 11a and a frusto-conical divergent surface 20b of deflector member 20.

The operation of this atomiser is similar to that described for the FIG. 1 arrangement with compressed gas flowing from chamber 18 and liquid to be atomised from chamber 22. The gas flows at sonic velocity from chamber 18 and as the pressure decreases the velocity increases to supersonic as shown by FIG. 3. When the gas approaches portion 20a of deflector 20 the gas pressure increases and the velocity decreases so producing shock waves 30. The liquid film 31 is accelerated by the gas and maintained out of contact with deflector member 20 by the gas so effectively forming a divergent nozzle between deflector member 20 and liquid film 31. The acceleration of liquid film 31 reduces its thickness and causes shearing. The pressure fluctuations at the culmination of the supersonic velocities reached by the gas which produce the shock waves 30 cause vibration of the liquid layer and further shearing and break up occurs in a plane normal to the horizontal shearing.

What is claimed is:

l. An atomiser, comprising:

an annular distributor member, including a radially outer circumferential ring of axial liquid feed passages, and a radially inner circumferential ring of axial gas feed passages;

a first annular member, disposed adjacent one end of said distributor member, and including at least one opening therein communicative with said ring of gas feed passages and a plurality of radially outer axial apertures communicative with said ring of liquid feed passages;

a deflector member, coupled to said distributor member, extending through said opening in said first annular member, a convergent annular gas nozzle chamber being defined by said first annular member and said deflector member adjacent said ring of gas feed passages; and

a second annular member, disposed on said distributor member, and including an opening through which said deflector extends, said first and second annular members defining a convergent annular liquid nozzle chamber adjacent said ring of liquid feed passages.

2. The atomiser as recited in claim 1, wherein said second annular member includes a knife-edge disposed about the periphery of said opening therein.

3. The atomiser as recited in claim 1, wherein said deflector member includes a divergent portion at one end thereof which extends outwardly from said opening in said second annular member. 4. An atomiser, comprising: an annular distributor member, including a radially outer circumferential ring of axial liquid feed passages, a radially inner circumferential ring of axial gas feed passages, and an outwardly extending annular extension disposed at one end thereof between said inner and outer rings of feed passages;

an annular member, disposed on said distributor member, and having a radially inwardly extending edge at one end thereof, said edge of said annular member and said annular extension forming an annular, convergent liquid nozzle chamber adjacent and communicative with said ring of liquid feed passages; and

a deflector member, coupled to said distributor member and extending outwardly from one end thereof, said deflector member and said annular extension of said distributor member forming a convergent annular gas nozzle chamber adjacent and communicative with said ring of gas feed passages in said distributor member.

5. The atomiser as recited in claim 4, wherein said deflector member includes a divergent surface, disposed adjacent said annular extension of said distributor member, for forming in conjunction with said extension said convergent gas nozzle chamber.

6. The atomiser as recited in claim 4, wherein said radially inwardly extending edge of said annular member includes a radially inwardly convergent inner surface for forming said liquid nozzle chamber.

7. The atomiser as recited in claim 6, wherein said distributor member includes a first threaded portion on the outside surface thereof and a second threaded portion on the inner surface thereof, said annular member includes a threaded portion on the inner surface thereof for threadably engaging said first threaded portion of said distributor member, and said deflector member including a threaded portion on the outside surface thereof for threadably engaging said second threaded portion of said distributor member.

8. The atomiser as recited in claim 7, wherein said deflector member includes an additional divergent portion extending outwardly adjacent said inwardly extending edge of said annular member.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US978860 *Jun 23, 1910Dec 20, 1910William DietzHydrocarbon-burner.
US1002594 *Aug 22, 1910Sep 5, 1911Walter R GroganOil burner.
US1075742 *Dec 12, 1912Oct 14, 1913Jacob WeintzBurner.
US1793897 *Aug 20, 1928Feb 24, 1931George L BarnesOil burner
US2089673 *Jul 22, 1935Aug 10, 1937Steinmann KarlOil atomizer
US2917386 *Sep 9, 1955Dec 15, 1959Aeroprojects IncHomogenizing method and apparatus
US3009826 *May 24, 1957Nov 21, 1961Aeroprojects IncProcess of forming a dispersion of aerosol particles and process for coating solid particles with said dispersion
US3534909 *May 21, 1968Oct 20, 1970NasaControl valve and co-axial variable injector
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4014961 *Apr 21, 1975Mar 29, 1977Vitaly Fedorovich PopovEjector mixer for gases and/or liquids
US4361285 *Jun 3, 1980Nov 30, 1982Fluid Kinetics, Inc.Mixing nozzle
US4483482 *Feb 2, 1982Nov 20, 1984Lechler Gmbh & Co., KgDual-material atomizing nozzle
US4592506 *Dec 21, 1984Jun 3, 1986Canadian Patents And Development LimitedWear resistant atomizing nozzle assembly
US4721252 *May 14, 1986Jan 26, 1988Slautterback CorporationHot-melt sputtering apparatus
US4768718 *Apr 10, 1987Sep 6, 1988Slautterback CorporationNozzle with internal valve for applying viscous fluid material
US4931225 *Mar 1, 1989Jun 5, 1990Union Carbide Industrial Gases Technology CorporationMethod and apparatus for dispersing a gas into a liquid
US4946105 *Apr 12, 1988Aug 7, 1990United Technologies CorporationFuel nozzle for gas turbine engine
US5456415 *Apr 7, 1994Oct 10, 1995Gardner; James J.Atomizing nozzle for liquids
US5799877 *Jan 3, 1996Sep 1, 1998Exxon Research And Engineering CompanyFluid distribution across a particulate bed
US6102308 *Apr 2, 1998Aug 15, 2000Task Force Tips, Inc.Self-educing nozzle
US7686093Oct 31, 2007Mar 30, 2010Victaulic CompanyDual extinguishment fire suppression system using high velocity low pressure emitters
US7721811Jun 13, 2006May 25, 2010Victaulic CompanyHigh velocity low pressure emitter
US7726408Jun 13, 2006Jun 1, 2010Victaulic CompanyFire suppression system using high velocity low pressure emitters
US7921927Mar 29, 2010Apr 12, 2011Victaulic CompanyGaseous and liquid agent fire suppression system using emitters with closed end cavity deflector
US8141798Apr 8, 2010Mar 27, 2012Victaulic CompanyHigh velocity low pressure emitter with deflector having closed end cavity
US8376059Apr 8, 2010Feb 19, 2013Victaulic CompanyFire suppression system using emitter with closed end cavity deflector
DE4213518A1 *Apr 24, 1992Oct 28, 1993Pierburg GmbhLiquid-fuel nozzle with coaxial fuel and air pipes - has annular non-throttling fuel outlet and annular air outlet with throttling effect
EP0085583A2 *Feb 22, 1983Aug 10, 1983Lee, Smith & ZickertLiquid atomizing method and apparatus
WO2011050377A1 *Oct 28, 2010May 5, 2011"Dumag" Brenner-Technologies Ges.M.B.H.Burner nozzle
Classifications
U.S. Classification239/424, 239/524, 239/589.1, 261/DIG.780
International ClassificationF23D11/34
Cooperative ClassificationF23D11/34, Y10S261/78
European ClassificationF23D11/34
Legal Events
DateCodeEventDescription
Aug 19, 1982AS02Assignment of assignor's interest
Owner name: NORTH AMERICAN DECAFIX, 5870 FAIRHAM RD. HAMILTON,
Effective date: 19820801
Owner name: PAUL, KOPPEHELE H.
Aug 19, 1982ASAssignment
Owner name: NORTH AMERICAN DECAFIX, 5870 FAIRHAM RD. HAMILTON,
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:PAUL, KOPPEHELE H.;REEL/FRAME:004026/0137
Effective date: 19820801
Aug 4, 1982AS02Assignment of assignor's interest
Owner name: DECAFIX LIMITED
Effective date: 19820429
Owner name: KOPPEHELE, H. PAUL 5870 FAIRHAM ROAD, HAMILTON, OH
Aug 4, 1982ASAssignment
Owner name: KOPPEHELE, H. PAUL 5870 FAIRHAM ROAD, HAMILTON, OH
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:DECAFIX LIMITED;REEL/FRAME:004022/0632
Effective date: 19820429