Multi-physics fuel atomizer and methods

MULTI.PHYSICS FUEL ATOMIZER AND METHODS TECHNICAL FIELD 10001] The present, disclosure .is directed to. fuel-:gystcms,.-and more particularly directed "to, fuel delivery syStems ,that U.sle:mult:ip!¢; stages to enhance evaporation, o:f the. fuel.

BACKGRO.UN O 100021 Many typ,es o!f:ide,vJices ha:re been developed over theyears for the.

purp0se' of converting liquids :into aerosois or,fine particles re 0 dily converted into a gas-phase. Manysuch devices have been d evei0ped, for! example, to. prepare fuei for use in imernal combustion engines. TO optimize fue! oxidation within an engine's cotnbustion chamber, the fuel inUsi 'be. vaporized,. hom0genizcd with air, and in a chemically-st0ichiometri:c gas-phase .mixture. Ideal, fuel atomization and yap0fizati9n enables 'morc e completed combustion and consequentl ;tower. engine OUt pollution.

|0003] ,MOre specific'aily, relative tO i nltemal .combustion engines, stoichiometricity is a; condition wher,e the amount of oxygen .requirefl to completely burn a given amount of fuel :is supplied in a homogeneous mixture resulting in opiimaliy ¢0rreclt combustion with no residues remaining, from: incomplete or inefficient oxidation. Ideally,: t he fuel should be c0mpletcl'y: Vaporized,. intermixed with air, and homogenized prior tO ignition for proper Oxidation. Npn-vaporized • fuel droplets do not ignite or conibust completely :in conventional internal and externaI combustion engines, which-degrades :fuel efficiency :and. increases engine out pollution..

100041 Attempts to reduce or control, emission byproducts by-.adjusting temperature and. presSure?, typically affects the NOx bypr0duc.t: :To meet emission t, standards, these residuES must bedealtwith, typically r,.equifing after treatmen6:in a catalytic converter Or a--scrubber Such treatment of these residues results: in additional fuel costs t0 0peratc..the catalytic converter or-scrubber' and: may require additional component costs as well as packaging and! miss imp!ications.

Accordingly,. any redueti'0n in. engine out residuals resulting from incomplete combustion, wou'ldbe econ0tnical!y and .environmenta!lybeneficial.

[0005:!. Aside from the problem s discussed .above, a: refuel that is :not completely vaporized i'na chemically stoichiometric;, air/fuel mixture :causes the combustion .engine.to perform at less-than: peak.efficiency:: .A smaHe r portio n of, the:

fuel's,, chemical energy is conyer:ted: to me chanicai: -energy when fuel is :not completely combusted..Euel, energy is. wasted :and?unnecessary pollution is, created.

Thus, by" further breakirig down arid more completely vaporizing, the ,fuei air.:

mixture,better fuel efficiency-!may be available.

100061. Manta attempts have been made to alleviate-the above,describe d problems with respect to the!-vaporization and inc0mplete ftiel €0mbustion, fin automobile, engines,.for example, inlet port or direct fuel injection have,! almost.

universally tepiaced ca :buretion forfuel delivery. Fuel injectors spray fuel directly into the inlet port or cylind.e :, of the engine. and. are controlled electronically, Injectors facilitate more precise metering and control of the amount ot" fuel. delivered to each Cylinder independently relative, to carburetion.. This reduces for eliminates charge-transport time facilitating optimal transient operation. Nevertheless, the fuel droplet size of, a fuel injector spray is not optimal rind there is!ittle time forthe.fuel to mi-x with air prior to ignition.

10007] Moreover, it has been recently discovered that fuel injector sprays are accompanied by a shockwave in the fuel spray. The shockwave:may prevent the fue!. from fully mixing v,'i h air. The shockwave appears to limit fuel mass to certain areas of the piston, limiting the fuel droplets" access toair:

[00081 Other prior systems, such as heated injectors and heated° fuel rails have also been developed in attempts to remedy the problems related to fuel vaporization and incomplete :fuel combustion.

DISCLOSURE: OFTHE INVENTION 10009] The principles described :herein may addtes's some. of the abovedescribed deficiencies and others. Specifically; some .of" the principles described herein relate to liquid processor apparatuses and methods.

One aspect provides a fuel atomizer that-includes a housing having.

a fueririlet, at least one primary fuel exit-orifice, a :fuel impingement surface,, a t least one air, or oxidant,, inlet .-or supply channel, and a plurality of secondary atomizer .outlet orifices. Atleast one .primary orifice is positioned at the fuel inlet and is configured to disperse a stream .of fuel into a plurality of'fuel droplets. The. fuel impingement surface is configured and arranged to be contacted by the plurality of fuel droplets to break up the plurality of fuel droplet into a plurality of smaller secondary droplets and create a thin film of secondary fuel droplets on the impingement .surface.. At. least one pressurized, air channel is: configured to deliver an air flow into con.tact '.ith the secondarydroplets. The. plurality of secondary orifices.are arrariged to havethe secondary droplets pass through.:to exit the housing.

The s[ze of the .plurality ofsecondary droplets is reduced When PaSsingthrough i:the plurality of.secondaty: orifices.

100111 .At. :ieast one ::primary orifice .positioned .at the fuel in.let may be:

.arranged coaxially wfth the fuel impingement surface. The plurality of Secondary, droplets may. acc¢lerate to liigh, velocitY speed when passing:,th ough tl e.:piurality O£ secondary ior.ifices,, The, housing` may' be one at: .a manifold: a cylinder, a head Combustion chamber, and an intake port iiito a Cylinder hen d. The-fuel impingement surface may: be:arranged at:, an angle in. the range 0f'about, but not constrained or limited to, 90 degrees., tO "abOut 1.35 degrees relative: to a longi:ludinaI axis of the housing. The plura!i:ty .of Secondary orifices: may be arranged-at fan angle, between about 0 degrees::and about 90 degrees relaiive to a longitudinal axis: Of the housing.

The fuel atomizer may further compr se a fuel meter[ng"meinber thatdefines the primary fuel h 1 l'et orifice; 1001121 Another asiScCt iOf the present disclosure: :relates to a method of atomizing fueithat includes pro vidi.6g an ,atomizing device comprising fit least, one primary orifice, :.an impingement surface, a mixing ehambeq and a plurality of secondary orifices,.passing a stream oi"fuel through tile at least one primary orifice:

to createa plurally of first, fuel droplets, and €ontacting the.p:lurali[y of first fuel droplets against lhe impingement surface to break up the plurality of fuel droplets into a plurality of smaller sized Secondary droplets and create a thin fihn of secondary.droplets on the impingement surface'. The method als0 iiacludes mixing the .plurality of second droplets with a pressurized air flOW tO form a fuel/air mixture, passing, the fuel/air mixture: through the piuraiity of secondary orifices to:

shear i.he plurality of second dropletsinto a. p!ura!ity of smaller.sized third .droplets, and dispersing the plurality of third droplets from the. atomizing device.

The step of pr0yiding the atomizing device may include arranging at least One primary fuel orifice, iheimpingement surface, and plurality Of secondary orifices, coaxially. Mixing the plurality ofsecond droplets with a.pressurized air fl0w may include' delix, ering :a flow Of air in a direction that is at least pariiaHy radial. Passing the fuel/air.mixture through the. p:luralhy of secondary orifices., may include rapid acceleration of the fuel/air mixture to high.-velocity' speeds. The atomizing, device may further, include a fuel metering device that, defines.at: least one.

primary orifice, and passing astream of fuel .through the at least one primary orifice • with the fuel metering, device.

I00141 A further aspect of the present disclosure relates to a pre combustion fuel mixing device that includes a housing,..a valve, a first nozzle member; an impingement surface, a mixing, chamber, a plurality of air passages, a plurality of second orifices, and a dispersing nozzle. The :valve isl enclosed bY the housing and arranged to deliver a stream of fuel. The first nozzle member includes a plurality of first orifices, wherein passage of the. stream, of fuel through the plurality of,first orifices creates a .plurality of first fuel droplets. The impingementsurface=is arranged in a flow path of the plurality of first fuel droplets, wherein contacting the plurality of firs fuel droplets against the impingement surface break s ,up the plurality:of first fuel droplets into a plurality of smallei-.sized secQnd .droplets:. The p!ura!ityof angled air .passages leads into the• mixing chamber,.. wherein a flow of pressurized, air :is delivered thi-ough 'the. air passages to..mix ,with. the plurality of second droplets to: create a fue.!/,air mixture. The plurality of second orifices :are arrangedito have the. fuel ai!: mixture pass, whercin the. pluralitY Of secOiad droplets:

accelerate to high ve]o, city (e g:, sonic) speedwhen pass]ng:thr0ugh!he pluralky of sec0nd orifices':--to:reduce a: size of the, plurality of sec0nddr0p!et s to ap!ura!ity O£ smaller sized flaird dr0plets The disperSlng=n0zzle spaccs:i ipari t:hei p!urality ofthird droplets to permit an incre ised evaporati0n rate:ofthelpluraJity of third dropiets.

10015] ..At least portion oft-he impingement surface may be arranged at. an angle relative to a longitudinal axis of:the device. The. diSpersi ng nozzle may be.

removably mounted to the housing Or fully integrated as a single :component. The plurality, of angled airpassages may be arranged at an angle re!atiye!,t.o a longitudinal axis of the device.. The plurality of angled air.,pasSages may include a Secondary angle rela iv.e to he impingement surface, thereby .forming. a. compound angle that:

induces a helical ..rotation. to.: the pressurized air flow. The:plUrality of secondary orifices may be arranged atan angle relative to a longitudinal axis, of the de.vice 161 Another aspect of the present disclosure, relates tO a ,method of vaporizing I fuel that includes., providing a fuel a omizing .device that includes a fuel metering device, ,an impingement surface, and a plurality of outlet .orifices controlling a pressurized air flo,w to deliver air through the-housing and out Of the plurality of outlet orifices to create an air flow, and controlling a fuel supply to deliver a flow Of fuel from the. fuel metering: device onto-the impingement surface, the flowof fuel including a plurality :of first fuel dfoplets tha t break Upinto smaller sized .Sec0nd, fuel droplets upon :eontactfng the: impingement surface. The method .also includes mixing the second fuel droplets with t!!e a:ii" flow, moving Ihe second fuel droplets through the plurality of outlet orifices, the second fuel droplets breaking. up into small.ersized third fuel droplets upon exiting the plurality of outlet Orifices, :enharicing, accelerating or promoting rapid vaporization Of the third .fuel droplctsas :the third:fuel droplets disperse from the plurality of outlet 0rjfices. The.

method:may further include, c0ntr01Hng the fuel source.. to turn OFF the flow offuel:

while maintaiiiing the. air flow; and controlling the pressurized air source to: turn.

OFF the:air flow BRIEF DESCRIPTION::OF THEDRAWINGS 1001711 The accompanying drawir gs :illustrate certain embodiments discussed below and. area pai-t.'0f the specification.

10011,81 l lG 1 is a Perspecfi.ve view of an example fuel System in accordance with.thg.present disclosure.

I00i91 FIiG I2 is an exploded.perspective view of:the fuel System 0fFIG. 1.

100201 FIG. 3 is a side:view ofthe fuel system of FIG. 1.

100211 FIG,. 4 is:a top view of the fuel system.0f FIG. 1, 10o221 FIG. 5 is a front view of the fuel.system of FIG. i.

10o231 FIG. 6 is a cross-sectional side view of the. fuel system of FIG. 4 taken along cros.s-section indicators 4-4.

100241 FIG. 7 i:s a cross,secti0nal top view Of the fuel system of FIG.:3 taken along cross,section indicators 3-3.

100251 FIG. 8 is-a detaii,ed view.of a portion, of the fuel system,of FIG: 7 100261 FIG. 9 is a top view of another exfimP]e fuel System in:accordance with the present.disclosure..

[010271 FIG, 10 isia cross-sectional Side vie\ : of the fuel system of F, IG. 9 taken: along: cr0ss-section,indicat0rs 10-1 0, [0028!1 FIG. H is :a detailed view of a portion of the fuel system shown in:

FIG. ! 0.

[00291 F!G. 12 ,is, a: side view of another example fuel System in accordance witfi thepresentdiscloSure 1003011 FIG. 13 i 1 s:a bottom view of the fuelsystem of" FiG. 13, [00311 FIG. ,14 is across-sectional side view of the fuel System of FIG, 12 taken:along crossrs¢cti0n indicators 14-,i 41.

[00321 FIG,. 15 is. a detailed view Of a portion of the. fuel system of FIG. 14.

100331 FIG, 1:6 is a Side xiiew of an atomizer of the, fuel systemof F.1G. i.

10034] FIGi: 17 iS a rear ,.view-of the:atomizer;of.FIG.. 16, 10o35] FIG. 18 isa front view of the atomizer oi' FIG. 16.

10.0361 FIG. 19 is a cross-sectional view of the atomizer of F!G. 16 taken along cross-section indicators 19,19, FIG,20 is a cross-sectional view of ihe atomizer of FIG. 119 taken along cr0ss-section indicators 20-20.

FIG. 21 demonstrates a pressurization stage of oPeration of the fuel system of E1G. 1.

FIG. 22 demonstrates further development of the pressurization stage,of FIG. 2.1.

10040] F1G. 23 demonstrates a first orific e break up stage of operation of the fuel system of FIG, 1.

100411 FIG, 24 .demonstrates an .impingement:i break up stage of operation ofthe fuel :System of FIG. 1.

10042] FIG. 25 .demonstrates a thin film break up Stage of operation of the fuel system of FIG. 1.

EIG.26 demonstrates a sonic velocity break up stage of operation of the fuel system of FIG. 1, [00441 FIG.27 demonstrates a fuel purge stage of operation of the fuel system of FIG: 1:

[00451 EIG 28 demonstrates an air evacuation stage of operation of the fuel system of FIG. 1.

[0046! FIG. :29 illustrates an idle stage o operation of the fuel system oi" FIG. 1.

FIG. 30 is a.graph showing an example air and fuel sequencing, of a fuel. system according to the present disclosure.

[00481 Throughout the drawings, identical reference characters and descriptions indicate Similar, but not necessarily .identical elements.

BEST MODE(S) FOR CARRY, ING OUT THE INVENTION Illustrative embodiments and aspects.are describe below. It will, of COurse, be appreciated that in the development of any such actual embodiment, numerous implementatibn=spe¢ific. :dcc.i i0nS must be made to achieve' the deTel'opers' specific goals; such a s. compliance wi.th:system-related and business-.

related constraints,: that wil!vary from one implementation to another; MoreOver,:ff \#ill be aplSreciated ihat .-such a development effort migilt be Complex and time- ¢0nsuming, but would nevertheless :be a routine Undertaking for those of ordinary skil! in lhe art havSiag the benefit,ofthis disclosure., .As?uSed thrOughQtit the Sp¢cifica'tion and. claims, the term?'droplet".

refers to a .small "Sized drop :of liquid. The'drop of:liquid may have any .shape and volume. A droplet may include a. single drop of the Ji.quia or multipie .dr0PSl of the liquid combined together, possibly in a.seriai.arrangement. The \¥0i*ds 'fincluding" and "havi!ng,'': as used in the specification, 'including the claims, hay€ the. same meaningas the:word comprising:" .[00511 The.prelsent disclosure is djrccSed to fuel.preparation systems and methods, Howeveri.small particl e technology has benefits in many applications.such as ,high altitude or.low orbit.applications and underwater applications+ One.aspect of the present disclosure relates to the use of multiple physics phenomena to. change"a liquid state fuel: into a fine particle mixture readily convertible into a. gaseous state.

The change from liquid to gas may occur in a plurality of steps that each utilize a differentphysies phenomena. For example, a first ,step.may-:include breaking down a" Continuous stream of liquid fuel into a plurality of first droplets or strings of connected first droPlets by passing the stream of fuel through a single orifice or multiple orifices using liquid energy. In this step, a flUid stream under pressure may be: forced through small orifices of for example, a con'troiled metering device, to create initial lbrmation of the'first droplets Single or multiple metered streams may be employed to enhance the. initial formation of the first droplets and direct the.

droplets towardthe next stage.

In :a second step, the first droplets: are broken up through mechanical impingement utilizing liquid energy: In this second step, the first, droplets or strings of first droplets are impacted against an obstacle such as an impingement surface. This impact.resu!ts .in break, up of the first droplets into smaller sized second dr0plets due tO rapid, deceleration and considerable droplet deformation. The impingement surface is typically positioned Within an Optimized distance from the metering device to facilitate the break up of first droplets into smaller second droplets.

In a third Step, the film, or droplets leaving the impingement feature, experienco a high shear as they enter the surrounding air flow. The shear caUses further distortion of the droplets and further break up.

[00541 In a fourth .step the third droplets are sheared by passing through multiple orifices utilizing gas energy. The third droplets are introduced into an air flow within a mixing chamber to form a two-phase mixture of air and fuel droplets.

The two-phase mixture is forced through a secondary plurality of orifices where the third droplets are rapidly accelerated to high velocity (e.g,, sonie)-speed, The rapid acceleration sh.ears and breaks up the third droplets into smaller sized fourth droplets. Sonic, speed is typically in. the range of about 768 mph at. room .temperatui: 0r about, 330 m/s at.20°C.

10055:1 The system typically Utilizes up to sonic gas: velocities to cause droplet breakups SOnic velocity (or sonic: speed).is a function ofthe fluid properties and conditions.

Por air a) standard, seadevel temperature, ' pressure and humidity conditions?,, the spnic ve!0cfly !is about: 3.41. m/s, For compressed air a t 4bar, 350K:

thelsonic yelo.city .is typically abut 3715 m s: The. system may operat vfisling a ange of fluids, temperatures and pressures causing a chang e in the :sonic.. velocity..

However, the ratio ofthe..actual veiocity achieved t b ithe: sonic velocity (known as the Maeh number) Should 'remain relatively €onstantland may be =up. to .1.0.

100561 In a fifth step, 1he.fourth droplets are dispersed ih. aspray pattern in which ihe fourth: droplets 'are-separated ,from each. other... The: increased separati0n between fourth droplets :facilitates :faster vaporization doe t 9 10ga!ly steePer-vapor concentration gradients V herein there is less :interference :be!ween vapm; clouds OL adjacent droplets: A pressure differential present as !the fourth ..droplets are dispensed from the system may also tend to .increase,x, aporization rates-of theTourth droplets.- 100571 Turning now 'to the figures, .and in particular to FIG$, 1-8 ..and. 1620, one: embodiment ofa. fuel system t:0. i:s` shown. The fuel system 10 may -comprise, for example, a base 12, a fuel metering device 14, .and an atomizer 16.

The fuel system 10 may provide a premixed supply of fuel!and oxidant to a device such as, for example, an internal combustion, engine. FIG. 1. illustrates the fuel system I0 in a manifold application wherein the base .12 defines at least in part a manifold for use iri a.combustion engine.

[00581 The. base !2 is a. generally rigid structure that may-be made of metal, ceramic., composite, plastic, or .othermaterials. The base: 12 may enclose a number of "internal components. The base 12.may include a number, of cavities Or seat features within which, various components are mounted. For example, the.base 12 may ineliade an atomizer, cavity 20 within which at leaSt,.a portioh of the fuel metering device 1.4.and atomizer 16 are mounted. The bas.e 12. may,: also.,include a dispense cavity :22 wherein the atomizer "1.6 dispenses a two-phase air/fuel spray; The base 12 may alsOinclude an air intake asse nhly24 that provides a.supply of air to the atomizer 1.6. The base 12 may comprise any size or. shape. -The base i2 may be configured in othet embodiments inthe form:of, lbr.example, abase poi-ti0n of'an intakeport 112 (see FIGS. 9=11,) or a base portiOn: of cylinder hi ad 2.12 (see FIGS.

12-1:5) as described in more:detail below; 100591 Referring tOFIGS. 2 and 8,the fuel metle?Jng device 14 includes-a valve :assembly 30 find an 0utlct 32 pgsitioned at a distal end. 34. A t'uel metering device 14 may be configured toprovide controlled fuel flow to the:atornizer 16 The fuel metering..de ice !4 may include at least 'one orifice that 'provides break up:of.a • stream offuel into a plurality of droplets or !strings .of dr0plet•s, Offuel. In some examples, the fuei..meter[ng device 14 includes-a plmiality of orifices.. A.supply of fuel is delivered from the fuel metering device, under• pressure and forced through a relativelY, small orifice or orifices for initial formation of droplets. Multiple metered streams of droplets may be created, as fuel exits the, outlet.of the fuel metering device 14. The Streams of droplet3 may be directed toward another portion o "the.atomizet.

such as an impinge.ment.surface-as described in further detail bcloxv.

1.0.0601 !n! some embodiments, features Of the fuel.metering device 14. may be. included, with tile atomizer .1.6.: For:examp!e, one or more orifices used.ito create droplets :from the supply of fuel controlled by .the fuel m.eter-ing device i4 may. be integrated into the atomizer !.6; In 0ther..arrangements, .features of.:the: atomizer 16" ma3 be: mt.egrated :inio the: fuel metering., device 14 .... In, some exampies : .the fuel metering.device 14 and atomizer !6 may be' integrally formed or assemb!ed i s a single device.

The fuel.metering device 1: I, may be an..off-the-she!f :fuel metering device, fuel injlector, or6thef readily available fuel metering..'or control device. In at least: one example, the fuel metering device 14 may be any device that provides a controlled flow of fuel :to the atomizer. 16 and :directs that flow of:fuel-onto surface of the atomizer such -as an impingement stirfaCe. In one example, the.fuel metei'ing device 14 may be a bore:., hole injector that provides a single stream..of droplets or strings of dropletS offuel, in 0ther examples, the fuel metering device 1.4 :provides two or more streams of c!r0plets, a partially broken stream of fuei, or a continuous stream of fuel.

10062] .Referring now.-to FIGS, 2,_ 8 and 16-20,. the atomizer 16 includes :a housing 40, a fuel metering device Cavity 42-, and a fuel inlet 44 The housing 0 is mounted within the atomizercavity 20. Of the base 12. The housing 40 defines the fuel metering device cavity 42, which cavity is sized to receive at least a portion of the fuel metering device 14. First and second pressurized air sealing members 56, 58 may be positioned between the housing 40 and the ,atomizer cavity 20. A third sealing member 60 may be.posil ioned between the fuel meteririg device 14 and the fuel metering device CavitY 42 within the housing 40. The first and second sealing members56, 58 may be positioned)on opposing sides of an air inlet into the. atomizer 16,. for example., the air intake assembly 24, The third .sealing member 60 may prov, idea fluid-tight seal between the housing 40 and the atomizer '1:.6..

The .atomizer 16 also includes a fuel inlet, 44 an impingement.

surface 46, a plurality of air channels 48, a mixing, chamber 50, and a plurality of secondary outlet orifices 52 in the outlet 54. A face, Of the outlet 54 .may be.

perpendicular to a longitudinal axis of the housing 40, ormay bearranged at a nonperpendicular angle.relatiVe tO the 10ngjtudinal axis 'of the housing :40 to form.a conical outlet lace that provides a quagi=perpendicula exit face .to the secondary orifices 52. The fuel inlet. 44 may be positioned in: alignment With the:. 0 utle 1 32 of:

the fuel metering device 1.4. The fuel inlet 44 maY define a. single inlet orifice or a.

plurality Of inlet orifices through which the supply .of fuel provided by the .fuel meteringdevice 14 passes 'tO createdroplet break up asi the pressurized flow of fuel moves irito 'the atomizer 16.

10064] The ,impingement surface 46 maybe arranged in alignment, withthe outlet 32 of the fue! metering device 14 and.the fuel niet 44 of the .atomizer 16., In some arrangements, the impingement surface 46 is arrangedcoaxially with the outlet 32. The impingement surface 46 may have a generally conical shape, which may further be diminished to represent a fiat i.e.,. planar) surface. In at least one example, the impingement surface 46 includes a portion that is arranged at an angle 74 (see. FIG. 19) relative to a longitudinal axis 72 ofthe atomizer. 16. Typically the angle. 74 is. in 'ther, ange of:abo:tit 0 degrees (o about 60 degrees, aridmorepreferably in the range of about 0 degrees to about 30 degre-es. Typit:h!ly,:,the smaller .the angle .74,. the ,greater-amount. of impact ,:force exerted when ihe, droplets contact the.

impingement,surface 46 to cause brea k up, of the droplets: :.Some of the droplets that.

contact the.,impingement surface 46 rebound off of the:impingement surface 46 into the mixing claamber 50. The greater the angle 74 the greater', th( likelihood Of defle( ti sn.of'the droplets :from.the impingement surface 46 .with 'less chance ofbreak Up ofthe droplet occurring.

!00'651 The :impihgement: sui:faee 6:, is.. shown ha,¢ing a generally conical shape with linear, surfaces..In other, arrangements; the impingement: surface 46.inay have a contoured Shape .or inc:iude portions ihat are contoured: iln some .arrangements, the. impingement, surface 46 'may be slightlY concave 9r recessed.

[00661 The: impingement surface: lilly include at'i leastl one surface feature such as. a plurality .of .protrusions, grooves, divots; or..other,. Skype of irregularity.

Providing a surface feature may enhance b eak-up offuel droplets .when contacting the impingemen! surface 46. The, impingement-surface. may be,.sufface treated or constructed of diffcring material in support of limiting anY surface .contOur change from the resulting ,continual impingement.

[00671 The. impingement surface, 46 may include an ,extended or-enhanced edge 76 having. overhanging, serrated or other fea(ur, es. Fuel dropletSor portions of fuel droplets that contact the impingement surface 46 may move along the impingement surface, 46 to the edge 76 where the droplets are further broken up at the edge 76 as the droplets mov.e into the mixing chamber 50. In some arrangements, a thin film of droplets, of fuel may Collect along the impingement surface 46 and move radially, outward to the edge 76 where the-droplets are broken up. into smaller sized droplets.. The creation ofa :thin film of fuel may occur coincidentally With break up: of droplets upon.impact, of the impingement surface 46 and rebounding of droplets ofvarious sizes alter contacting the,impingement surt'ace 46.

[0068 i The impingement surface 46 may have any sized: or :shaped construe(ion. Any portion of the impingement .surface .46 :may any desired orientation relative tO 'the fuel metering device 14 and longitudinal axis 72 of the atomizer 16.

I0069:1 The pressurized air. channels 48 of.the atomizer 16 :may%e radially spaced apart :around "the :impingement. surface 46 to-provid e, a flow 0f"air to the mixing chamber 50-and: areas surrounding the impingement surface 46. The air channels 48 may extend to. an outer periphery of the atomizer, i 6 where: a supply of pressurized airis provided vi a, for example, the air intake assembly 24 (see FIG, 6)- The air channels 48 may. be arranged at an angle 78 relative to the longitudinal axis 72 (see F!G. 19). The air channels 48 may have a maximum dimension .Di (i.e.

maximum diameter). The amount.of air delivered to the mixing chamber 50 may be determined at least, in part by the number of air: channels 48 and. the dimension-D The angle 78 is typically in the-range of about 3.0 degrees to about 90 degrees, and more preferably in the range of about 30 to about 60 degrees. The dimension Di is typically in th e. range .of about 0.5 mm to about 5 mm, an'd more preferably in the range Of about.. 1 mm tO about 2 mm.

100701 in addition :to being 'arranged atan !angle :78 relative tO the, longitudinal axis 7!2, the air channels 48 may also be arranged at=an ang[erelative to.

atangent at an 0utersurfaCe. of the at0mize 16. That is to say,,the air channels 48 may comprisean angle from tangent greaterthanO degrees:and less than:' 90 degrees, wherein 9'0 :degrees is:aligned.radial or centere&. This additional: angled relationShip of the air channels 48: may provide a compound :ang]e fro:the :air hannelsi48 and" may assist in providing a heiicai rotation to the exiting air, the!;eby generating swirling-orv0rtex eff'ect, Within the niixing: chamber 50. The vortex effect near t!ae.

impingement surface: may enhance break UP, .as well as assist in enhancing evacuatio.fi of residual pari:i:des during. fuel purge,, whereas thevortex effect in 'the annulus region :may enhance uniformity of-two-phase Mr/fuel mixture distribution i¥om the secondary outlet orifiees. .An:;€xample device. ithat implements: vortex chambers within: ,a fuel m:ix:ing chamber is disclosed in U.S,. published Patent, Application N0..2007/0169760, which is-.incorpora!ed herein ,in its :entirety by. this reference.

10071.1 Themixing chamber 50 maybe defined at least in part :surrounding the impingement surface 46 radially outward.from the:!napingem'ent:surface.46. The :mixing .chamber 50 may ilso include an area within, the atomizer 16 defined between the impingement surface '46 and the fuel inlet 44. The mixing Chamber 50.may bea continuous chamber and may extend axially away from the impingement surface 46 toward the outlet 54. The mixing chamber 50 may define a flow pat.h£ora ,mixture Of air and fuel droplets to travel toWard the secondary orifices 52. at. the Outlet 54., Typically.; the mixing chamber -50 is sized and arranged to prox, ide a space within which a flow of air provided through the air channels 48 -may mix with fuel droplets (i.e,, at least those fuel droplets that have been broken up upon contact .with .the impingement surface 46).tt create an air/fuel .mixture.

The impingement surface 46 may .be. defined as a structure-that extends-orprotrudes :int0i:t!ie. mixing., chamber 510. Alternatively, the miXing.Chambe:r nlay be define d as a. space such as a cylindrical, cavity or arinulus that is defined .around an impingement surface and the structure that defines and suppor,ts the impingement surface 46. The .bottom 0fthe annulus may be:p!anar or contouredto support enhance fuel purge.

The.:sccondary. orifices52 may be positionedat: an outlet 54 0f the atomizer .16. The secondary orifices 52: may :be positioned .radially and circumferentiaHy spaced apart The secondary orifices 52. mayeach individually have amaxiinum dimension D 2 (e.g., maximum diameter) and: be arranged at an angle 80 '(see FIG. !5). The col!cctix, e-cr0ss.-sectionai :area defined bythe secondary orifices 52 is typically less than .the. cross-sectional areaof the :mixing chamber (e.g.., cross-sec!i0n.a! area at the .interface between ihe mixingchamber 50 .and the secondary orifices 52Consequently, .fluids under pressufe located within. 'the mixing chamber 50: tend: to' accelerate as they move. into and through the SeCondary orifices 52. In at least some examples, the two-phaseair/fuel mixture present in the mixing chamber 50 aceelerates: to. high velocity :(e,g.,.. sonic) speeds while passing through the secondary orifices52. This rapid acceleration tends to break up the fuel droplets in the fue!/air mixture to form a plurality of smaller-sized fuel droplets.

Contacting the .fuel: droplets against the .entrance into and sidewalls of the smaller sized secondary orifices 52 may physically break up at least some of the droplets of the air/fuel mixture, 10074] The dimenSiOn D 2 iS ypical!y .in the range of about 0,2 mmto about.

3 mm and more preferably in the range of.about 0.5 mm to :about 1..5 m. Typically, the angle 180 is .in the. range of about 0 degrees: to about .45 degrees relative to 'the longitudinal axis 72, and morepr, eferably in the 'range of about 0 degrees tO about degrees. The angled arrangement of the secondary .orifices 52 tends to disperse ,the fuel mixture tO separate the fuel droplets: as they exit the outlet 154. This dispersion of the fuel droplets creates additional separation between the droplets that may accelerate:,Vaporization due io locally steeper vapor concentration gradients available because the vapor clouds, surrounding each of .the droplets have less iriierference with each other.

The outlet 54 of the atomizer 16 may be constructed as a separate piece that is mounted to the housing 40 in a separate step. FIGS-. 2 and 19 illustrate the construction of outlet 54 as a separate piece. In. other arrangements, the outlet 54 may be integrally formed With the.housing 40. Typically, the outlet 54 defines:at least a portion of the secondary orifices 52. In some arrangements, the outlet 54 when formed as a separate piece from the housing 40, can be exchanged with an outlet having different sized and angled secondary orifices 52. Different sized and anglcd secondary orifices 52 may be-more useful for a given fuel being handled by the fuel system 10. The number of secondary orifices 52 is typically in the range of about 2 to about 20, and,more preferably in the range of about 6. to about 12. The number and relative positioning of secondary Orifices .52 may provide 'certain advantages.in disbursing.the.i'uel droplets.

• 10076] Referring nowto F..IGS. 9-i l., another example fuel. system .100 Shown. The fuel System 100 includes a base 112 thatis constru.cted as an. intake port to an engine :cylinder head, The base l t2 includes an.. atomizcr cavity .i20, a.

dispense cavity 122, and a cylinder 126..A valve 128 and ignition member 129 :are.

exposed .wiihin'the cylinder 126. .Dispensed fuelfrom an atomizer 16 is delivered from the dispense cavity i22 and then into the cylinder I26 where the fuel. is ignited by the ignition member :after-piston compression129.

[00771 Referring now to.: F!GS. 12-15, another example fuel system 200 Shown. Fuel system200, is constructed as a direct injection:system whereih thebase 2]2, which is constructed as a cylinder head, i s mounted to a cylinder 226. The bas e 212 includes an atomizer cavity:220 and a dispense cavity 222. An ignition member 229 is .expOsed within the. cylinder 226. :Fuel dispensed: from the atomizer directly into the cylinder 226 is ignited by the ignition member. 229 after piston compression.

Other types of fuel .systems may benefit from the use of a fuel metering device and atomizer, as described herein. The fuel systems described herein may be compatible with many different types of fuel such as, for example, gasoline, diesel fuel and liquid propane. The relatively simple construction of the atomizer, which implements basic physics phenomena related to liquid and gas energy, orifices, physical impingement, pressure dffferentials, vaporization, rapid acceleration, supersonic speeds, and other considerations may promote certain advantages such as, for example, improved vaporization of fuel atlower pressures; higher fuel flow rates for a given particle size,, reduced complexity in design and manufacturing thereby feduc!ng costs, and..less stringent 'tolerances' as compared to.:

other system s like direc t injection fuel injectors.

100791 The use of multiple physical., mechanisms to break, up fuei into smaller" sized droplets in. sequential order may issist iri ,sequentially breaking itlae droplets into smaller sizes:to enhance the.rate Of evaporizaiionlafter di..spensing from the .atomizer, The rate of evaporizati0 n of.a fuel droplet :increases exponentially as the di0rnet:er.o:f'the: droplet decreases. The: rate 0fdiffusion from:'tfie droplet to the liquid vapor fnteH'ace between.the: :liquid core, and .vapor surrounding the fuel droplet maybe expressed :by. the following Equation 1 :

[i- ,.7 In 1, , 1 ='4 rpr D 1 1 ,.a ,,,,milnl """"'"" l' Equafio.n 1 Y 1 iqiud.m = Mass {factiOn of vapOrfar fromthe surface Y 1 iq.uid,! -- MaSS fiac'tion.gf vapor at the liquid/vapor interface cliquish = Mass transfer rate:of.liquid.

Dliquid;vgpor = Mass diffusivity p = density of the liquid ri = radius of droplet n= 3.1415,93 100801 Referring now to FIG. 21-29, an example method of dispensing.fuel with a fuel system is shown and described. The fuel system 10 is referenced throughout FIG. 21-29. Other fuel system embodiments such. as fuel systems 100, 200 may be operated similarly.

The method is initiated, by: creating airpressure within the.:atomizer.

i 6 by turning ON an air supply w.hiie maintaining the fue!.,supply OFF, as. shown in FIGS. 21 and. 22. :This step may also be referred to. as pressurizing the atomizer 16.,.

After sufficient air pressure: is obtained within the atomizer -1.6, excess .air flow passes through the: secondary.orifices 52 out of the Outlet 54. The airflow 90;may be referenced as a plurality of arrows:90.

In a .following operation step, while, maintaining the airflow ON, a supply of fuel is turned ON and delivered by the fuel metering device i4 :into the atomizer 16. The .supply of fuel is in thc form.of at least:one stream of a plurality of fuel droplets or a string of fuel droplets that are directed towardthe impingement surface 46 as shown in FIG., 23. Upon contacting the impingement surface; the first fuel droplets 91 are broken up into smaller Second droplets 92as shown in FIG..221.

A thin film of !second droplets may collect on the impingement surface 46 as shown in FIG, 25,. Additional tYacturing of the first and second droplets, 91, 92 may occur as the thin film travels over the edge 76 ,of the impingement surface 46. The second droplets 92 mix with the airflow 90 to createa two-part mixture of air and second droplets within the :mixing chamber 50. Tile fuel/air mixture moves under:pressure towards the secondary orifices 52, wherein rapid acceleration occurs to increase the speed of the second droplets. The second droplets may reach supersonic,speeds. AS the second droplets 92 pass through the secondary orifices 52, the second droplets 92 are broken up into smaller sized third dr0plets 94 that are dispersed at the outlet 54 as 'shown ,in F, IG. 26.. As.the third droplets.194 are dispersed from the .atomizer:lO, the third.droplets: may separate from each other. An vaporization rate f0r the third dropiets-may,'iricreaSe, as the, third, droplets ,94 continue to reduce ,in size.

!00841 lria further operati0n Step, the fuel ils :turned ;OFF'while the, airflow is maintained ON as i shQ\yn: in FIG. 27. This:step may be refi:rred to as, a, fuel purge as the,. airfloW carries any remaining fuel within, the atomizer :16 Out througli the outlet 54.

[00851 :In a fUrther. Operation: st p, air'is evacuated from the atomizer 16 by.

turning OEF the airflow While mair aining the fuel OFF.as Shown in F!G, :218. l n a final operation: step, the airflow and. fuel: are maintained in .an OFF state;so that the fuel system remains idle.

10086] FIG. 30 illustrates the sequencing of turning .tlie aiYflOW ahd. fuel supply ON and OFF relativeto ignition inthe cylinder of:a n engine (below toP dead center (BTDC)). Typically, ,for a manifold 0! :intake port instal!aiion, the air is maintaine d ON between about 360 degrees and about 1:80 degrees BTDC while the fuel is maintained ON: tbr a timeframe between about3 60 degrees .and about :18:0 degrees BTDC tha.t is less than-how long:: tile airflow is. maintained ON :and also within the .range of 360 degrees to 180 degrees BTDC when the air is, maintained O.N.

100871 The preceding description has been presented only-toillusttate and describe certain aspects, embodiments, and examples of the principles Claimed below. It is not intended to, be exhaustive or to limit the described principles to any precise form discltrsed. Many modi:fications and variations are possibl°e in light the., :above disclosur.e. ,Such modifications are contemplatedl by "the i nvefiio:r ai d within the:, Scope, oF the claims The seope..oftl]e principles, described is! defined owing, elaim