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Publication numberUS3692245 A
Publication typeGrant
Publication dateSep 19, 1972
Filing dateJan 15, 1971
Priority dateJan 16, 1970
Publication numberUS 3692245 A, US 3692245A, US-A-3692245, US3692245 A, US3692245A
InventorsArthur Michael Needham, David Tindall
Original AssigneeJ & T Engineers Ascot Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Fluid atomizers
US 3692245 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

United States Patent Needham et al. [451 Sept. 19, 1972 [54] FLUID ATOMIZERS 1,436,189 3/1966 France .'.....239/488 [72] Inventors: Arthur Michael Needham, Backwell;

David Tindall, Dibden Purlieu, both of England Attorney-Lawrence E. Laubscher [73] Assignee: J. & T. Engineers (Ascot) Limited 22 Filed: Jan. 15, 1971 [57] ABSTRACT The invention comprehends a fluid atomizer compris- [211 P 106516 ing an atomizer nozzle having a discharge orifice communicating with arcavity in said nozzle of convergent 3 Foreign Application priority Data axial section towards said discharge orifice, and a swlrler insert snugly fitted III said cavity and having an Jan. 16, Great Blltall'l ection complementary thereto wifler insert being axially spaced from said discharge orifice to [52] US. Cl ..239/488, 239/494 define between the smaller cross sectional end of said [51] Int. Cl. ..B05b l/34 swirler insert and said discharge orifice a swirl [58] Field of Search ..239/46 1 463, 486, 487, 488, chamber forming p of ai i y, i swirler insert 239/489, 493, 494, 496, 497 having a plurality of passages extending in and along its peripheral wall to provide for fluid flow, between [56] Rderences Cited the interfitting peripheral surfaces of said atomizer nozzle and said swirler insert, through said passages UNITED STATES PATENTS each of said passages extending at its discharge end adjacent said swirl chamber in a direction generally 262,183 8/1882 I-Iogan ..239/487 tangential of Said chamber so that fluid g g 1,089,406 3/1914 Fittsm ..239/488 X from said discharge end will flow in an axial direction St. Clalr X the surface of said 1,731,813 BIOOITI X chamber and thereto 2,776,862 1/1957 Bloom ..239/488 X 9 Claims, 10 Drawing Figures FOREIGN PATENTS OR APPLICATIONS 1,127 5/1909 Great Britain ..239/493 Pl 7 p2 pmmsnsms I972 3,692,245

SHEET 2 0F 2 F/c. IO.

pwvlbl INVENT'OR 5 Y.g j

ATTORNEY FLUID ATOMIZERS This invention concerns improvements in or relating to fluid atomizers.

According to the invention there is provided a fluid atomizer comprising an atomizer nozzle having a discharge orifice communicating with a cavity in said nozzle of convergent axial section towards said discharge orifice, and a swirler insert snugly fitted in said cavity and having an axial section complementary thereto, said swirler insert being axially spaced from said discharge orifice to define between the smaller cross-sectional end of said swirler insert and said discharge orifice a swirl chamber forming part of said cavity, said swirler insert having a plurality of passages extending in and along its peripheral wall to provide for fluid flow, between the interfitting peripheral surfaces of said atomizer nozzle and said swirler insert, through said passages, each of said passages extending at its discharge end adjacent said swirl chamber in a direction generally tangential of said chamber, so that fluid emerging from said discharge end will flow in an axial direction generally following the peripheral surface of said swirl chamber and tangentially thereto.

In order that the invention may be well understood there will now be described some embodiments thereof, given by way of example only, reference being had to the accompanying drawings, in which:

FIG. 1 is a cross sectional side elevation of a fluid atomizer assembly;

FIG. 2 is a cross sectional side elevation of an atomizer nozzle for said fluid atomizer assembly;

FIG. 3 is a side elevation of a swirler insert completing said fluid atomizer assembly;

FIG. 4 is a front elevation of the same swirler insert;

FIGS. 5, 6 and 7 are side elevations of three alternative swirler inserts, only one fluid passage being shown for ease of illustration, although it is to be understood that a plurality of such passages would be provided;

FIG. 8 is a front elevation of a further alternative swirler insert;

FIG 9 is a cross sectional side elevation of the fluid atomizer assembly, shown in FIG. I, mounted in a conventional fluid spray tube; and

FIG. 10 is a cross sectional side elevation of the fluid atomizer assembly, shown in FIG. I, mounted in a conventional fluid spray tube with provision for the return of fluid from the atomizer assembly.

The fluid atomizer assembly is primarily intended, for incorporation in an oil fuel burner suitable for use in a steam generating boiler or in any other application where the fluid has to be sprayed in the form of finely divided droplets evenly dispersed.

The fluid atomizer assembly, shown in FIGS. 1 to 4, comprises two components, the atomizer nozzle 1 and the atomizer swirler insert 2. The atomizer nozzle 1 includes a cavity In which in axial section is convergent towards a discharge orifice 10 of the nozzle. In each of the present embodiments, the cavity la is of conical configuration. The swirler insert 2 has an axial section complementary to that of the cavity la, i.e. in the particular case the swirler insert is conical, and is sized to snugly fit into larger end of the cavity la to define a swirl chamber lb between itself and the discharge orifice 10. The swirler insert 2 is normally clamped in the atomizer nozzle 1 by means of a capnut 3 and a tube 4 or by the capnut 3 and a tube 5, as shown in FIG. 9 and 10 respectively.

Fluid is delivered to the atomizer assembly under pressure by way of the tube 4 or an annular space 6 around the tube 5. Due to the swirler insert 2 being clamped in the atomizer nozzle 1, the fluid is constrained to flow between the swirler insert 2 and the atomizer nozzle 1 through passages 7 formed in the conical wall 2a of the swirler insert to run therealong and open into the swirl chamber lb tangentially thereto.

Due to the inclination of the passages 7 to the axis of the swirler insert 2, the fluid jets on leaving the constraint of the passages 7 tend to follow the conical wall 8 of the swirl chamber lb and have velocity components in both an axial and tangential direction.

In one particular swirler insert 2, shown in FIGS. 3 and 4, the cross sectional area of each of the passages 7 decreases in the direction of fluid flow due to the depth of each passage decreasing in said direction and the fluid is accelerated on passing through the passages 7.

In an alternative swirler insert 2 shown in FIG. 5, at the entrance to each of the passages 7, the axis of each passage is parallel to the axis of the swirler insert 2.

In another alternative swirler insert 2 shown in FIG. 6, the entrance to each of the passages 7 is radiused at to minimize the energy required to accelerate the flow of fluid from the tube 4 or the annular space 6 into the passages 7.

In another alternative swirler insert 2 shown in FIG. 7, the rate of change of curvature of the passages 7 is maintained constant.

In a further alternative swirler insert 2 shown in FIG. 8, each of the passages 7 decreases in width, normal to the axis of the passage, in a radially inward direction so as to reduce the cross-sectional area of each passage in the direction of fluid flow.

The fluid on leaving the constraint of the passages 7 of the swirler insert 2 is further constrained by the conical wall 8 of the atomizer nozzle 1. The circular cross sectional of the interior of the nozzle 1, normal to the axis of the nozzle, bounded by the conical wall 8, decreases, of course, in the direction of the fluid flow.

This convergence causes the fluid flow to accelerate in both axial and tangential directions in the swirl chamber lb until an edge 9 of the discharge orifice 10 of the nozzle 1 is reached. The force required for this acceleration of fluid flow is supplied by the difference in pressure between P2 and P3 as shown in FIG. 9 and FIG. 10.

The convergence of the nozzle wall 8 causes the separate fluid jets, as at the exit of the passages 7, to amalgamate in the swirl chamber lb. The fluid is emitted from the discharge orifice 10 with axial and tangential components of velocity, and on leaving the constraint of the orifice 10, the fluid forms into a conical sheet of an included angle B of uniform thickness which under the influences of various forces acting on and within the fluid, breaks into droplets.

By providing a suitable number of the passages 7 of a suitable shape and form, together with suitable sizes of discharge orifice l0 and included angles A of the nozzle wall 8, the desired characteristics of fluid flow, droplet size and spray angle B may be obtained.

The described fluid atomizer assembly is advantageous in that the desired value of axial and tangential velocity given to the fluid flow at the exit of the passages 7 is achieved with the minimum loss of energy,

resulting in more energy being available to impart further increases in axial and tangential velocity within the convergent nozzle bounded by the wall 8. For a given pressure P1 in the tube 4 or the annulus 6 and a given quantity of fluid flow, an improved spray is achieved than with conventional atomizers.

Again, because of the increased value of the pressure P2 for a given value of P1, at a given fluid flow, a greater pressure difference is available for the return of fluid from the atomizer in a system as shown in FIG. 10, thus a greater degree of control of the flow fluid to be atomized can be obtained without detriment to the quality of the atomization.

Further, since the fluid discharges into the swirl chamber lb having both axially forward and tangential components of velocity, friction due to drag on the conical wall 8 of the swirl chamber is reduced with consequential reduction in the rate of wear of that wall,

giving proper atomization for longer periods of service than is possible with conventional atomizers.

As stated, the area of each passage, in particular embodiments of swirler insert, as it approaches the swirl supply pressure Pl, so that by altering the length of the swirler insert 2, the discharge area of the passages 7 is varied, and thus the flow through the discharge orifice for a given value of the supply pressure P1.

The various constructional features of the different embodiments may be combined where appropriate.

What we claim is: l. A fluid atomizer, comprising a. an atomizer nozzle having a discharge orifice communicating with a cavity in said nozzle of convergent axial section towards said discharge orifice;

. a swirler insert snugly fitted in said cavity and having an axial section complementary thereto, said swirler insert being axially spaced from said discharge orifice to define between the smaller cross sectional end of said swirler insert and said discharge orifice a swirl chamber forming part of said cavity, said swirler insert having a plurality of passages extending in and along its peripheral wall toprovide for fluid flow between the interfitting peripheral surfaces of said atomizer nozzle and said swirler insert, and through said passages, each of said passages extending at its discharge end adjacent said swirl chamber in a direction generally tangential of said chamber, so that fluid emerging from said discharge end will flow in an axial direction generally following the peripheral surface of said swirl chamber and tangentially thereto; c. and means clamping said swirler insert within said atomizer nozzle, said clamping means including 1. flow tube means externally threaded at one end;

and 2. a capnut threadably connected with said flow tube means and in engagement with said atomizer nozzle to clamp said atomizer nozzle and said swirler insert against one end of said flow tube means. 2. A fluid atomizer is claimed in claim 1, wherein said cavity is of conical configuration and said swirler conical.

ins rt i al 3 Ailui atomlzer as claimed in claim 2, wherein the cross sectional area of each of said passages decreases towards said discharge end thereof.

4. A fluid atomizer as claimed in claim 3, wherein each of said passages decreases in width towards said discharge end thereof.

5. A fluid atomizer as claimed in claim 3, wherein each of said passages decreases in depth towards said discharge end thereof.

6. A fluid atomizer as claimed in claim 1, wherein each of said passages at its inlet end extends in a direction parallel to the axis of said swirler insert.

7. A fluid atomizer as claimed in claim 1, wherein each of said passages is curved and the rate of change of curvature thereof is constant through the length of the passage.

8. A fluid atomizer as claimed in claim 1, wherein each of said passages at its inlet end is radiused.

9. Apparatus as defined in claim 1, wherein said swirler insert contains a central axial passage, and further wherein said flow tube means includes a pair of concentrically spaced inner and outer flow tubes that define therebetween a flow path to the inlet end of each of said passages, said inner flow tube defining therein a flow path from said swirl chamber via said central axial passage.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3762652 *Aug 21, 1972Oct 2, 1973Barry Wehmiller CoNozzle for delivering a conic spray pattern
US4230273 *Feb 7, 1978Oct 28, 1980The Bendix CorporationFuel injection valve and single point system
US4260110 *May 26, 1978Apr 7, 1981Winfried WerdingSpray nozzle, devices containing the same and apparatus for making such devices
US5423488 *May 11, 1994Jun 13, 1995Davidson Textron Inc.Spray apparatus for mixing, atomizing and spraying foam forming components
US5464390 *Nov 29, 1993Nov 7, 1995Stryker CorporationSurgical multiorifice irrigation apparatus
US5860602 *Dec 6, 1996Jan 19, 1999Tilton; Charles LSpray plate
US5933700 *Sep 21, 1998Aug 3, 1999Tilton; Charles LDie pressing powdered metal to form an array of atomizers for spray plate
US6016969 *Sep 14, 1998Jan 25, 2000Tilton; CharlesLaminated array of pressure swirl atomizers
US6394366 *Oct 27, 2000May 28, 2002Spraying Systems Co.Spray nozzle assembly
US6533954Feb 27, 2001Mar 18, 2003Parker-Hannifin CorporationFuel injectors for dispensing fine sprays for ignition in gas turbine engines
US6550696Feb 27, 2001Apr 22, 2003Adel B. MansourIntegrated fuel injection and mixing system with impingement cooling face
US7083122Feb 20, 2003Aug 1, 2006Parker-Hannifin CorporationIntegrated fluid injection air mixing system
US7597275 *Jul 25, 2005Oct 6, 2009Isothermal Systems Research, Inc.Methods and apparatus for atomization of a liquid
US7611080 *Jun 1, 2007Nov 3, 2009Spraying Systems Co.Full cone air assisted spray nozzle for continuous metal casting cooling
US7621739Jul 25, 2005Nov 24, 2009Isothermal Systems Research, Inc.Injection molding apparatus for producing an atomizer
US8235706Sep 4, 2009Aug 7, 2012Parker-Hannifin CorporationMethods and apparatus for atomization of a liquid
US20110053103 *Aug 16, 2010Mar 3, 2011Irwin Industrial Tool CompanyTorch
US20110115105 *May 8, 2009May 19, 2011Blue Planet Environmental Inc.Device for mixing gas into a flowing liquid
US20110127682 *Feb 23, 2009Jun 2, 2011Blue Planet Environmental Inc.Device for improved delivery of gas to fluid
EP0004682A1 *Mar 21, 1979Oct 17, 1979Metallgesellschaft AgNozzle of the return-flow type
WO1995031287A1 *Apr 25, 1995Nov 23, 1995Davidson Textron IncSpray apparatus for mixing, atomizing and spraying foam forming components
WO2011156334A1Jun 7, 2011Dec 15, 2011The Procter & Gamble CompanyDispenser having non-frustro-conical funnel wall
WO2011156336A1Jun 7, 2011Dec 15, 2011The Procter & Gamble CompanyDispenser having convergent flow path
Classifications
U.S. Classification239/488, 239/494
International ClassificationB05B1/34
Cooperative ClassificationB05B1/3484, B05B1/3442
European ClassificationB05B1/34A3H, B05B1/34A3B4D
Legal Events
DateCodeEventDescription
Feb 25, 1982AS01Change of name
Owner name: SPECTUS ENERGY LIMITED
Owner name: SPECTUS OIL BURNER LIMITED
Effective date: 19820105
Feb 25, 1982ASAssignment
Owner name: SPECTUS ENERGY LIMITED
Free format text: CHANGE OF NAME;ASSIGNOR:SPECTUS OIL BURNER LIMITED;REEL/FRAME:003950/0761
Effective date: 19820105