Patent Application
20210148321
The present disclosure relates generally to an apparatus and method for creating an atomized liquid (which liquid may be volatile or non-volatile). In one embodiment, the present disclosure is directed to a fluid spray nozzle (or injector) used in the fluid delivery industry.
Improving the atomization of liquids (e.g., a volatile or a non-volatile liquid, such as water or certain coatings, respectively) for use in fluid delivery systems is an important aspect of nozzle design. A key aspect is the liquid particle size or the size of the liquid droplets as they leave the nozzle for application of the liquid for the intended purpose (such as atomization in an air stream or fine droplet application onto a surface). The atomization of water and/or alcohol, for example, is of particular importance to internal combustion (spark or compression ignition) engines. Conventional single hole, multi-hole and “swirl” type universal nozzles (which may be single piece design or multi-piece design with an outer, inner and securing mechanism) provide sub-optimal atomization of liquids (these conventional designs typically use an air shear and/or a swirl type atomization mechanism). The disclosed invention, through the application of jet-to-jet colliding geometries, provides for atomization while maintaining simple integration to universal nozzles, including both multi-piece and single piece nozzle designs.
Achieving effective atomization of liquids (whether for cooling, knock reduction, NOx reduction and/or improved combustion efficiency) is an important aspect of engine design and operation and provides significant advantages to the internal combustion engine.
Both liquid fuels and water are typically injected into engines. Fuels can be diesel-type fuels, gasoline (petrol), alcohols, and mixtures thereof. Alcohols include ethanol and methanol, which are commonly blended with gasoline. Water is also often injected into engines to provide an internal cooling effect, knock and/or NOx reduction. Because of the large coefficient of expansion provided by liquid water it has the advantage of being converted to steam during combustion.
Modern engines typically use fuel injection to introduce fuel into the engine. Such fuel injection may be by port injection or direct injection. In port injection, fuel injectors are located at some point in the intake track before the cylinder and the fuel is introduced into the air stream (which is generally close to atmospheric pressures for normally aspirated operation and up to 2-3 atm for forced induction applications). Atomization of fuels and other liquids injected into engines is important, as only fuel vapor can participate in combustion. Optimally, any injected liquid is atomized prior to contact of a stream of injected liquid with any interior surface of the engine. If liquid contacts surfaces at any time prior to combustion, such liquid can wash away lubricants and/or pool or puddle—resulting in sub-optimal combustion. Pooled fuel during combustion causes carbon deposits, increased emissions, and reduced engine power.
Evenly distributed sprays of water are important for heat transfer on heat exchanger surfaces (as utilized in boosted high performance engine applications), wherein water is sprayed onto a heat exchanger to increase heat transfer efficiency and provide additional cooling capacity. A common application in the automotive industry is the utilization of water or alcohol sprays onto the exterior of charge air heat exchangers to further lower the charge air temperature prior to introduction into the combustion chamber.
Fine droplet size and short liquid lengths are extremely important for the spray of, for example, water and/or alcohol into the intake track of an internal combustion engine, in order to maximize heat transfer from the hot air charge in a boosted internal combustion engine to the injected water-alcohol spray. Excessively large spray droplets can be carried into the combustion chamber, but they poorly participate in combustion, while washing engine lubricants from friction surfaces in the combustion chamber (leading to undesirable premature wear or possible failure of the components). In addition, sprays with long liquid lengths impinging on surfaces internal to the air intake track of an internal combustion engine may pool or coalesce into large puddles (which, if ingested by the engine, can cause significant damage, and in extreme cases, cause hydraulic lock of the engine).
Besides combustion engines, atomization of fluids is also extremely important for creating medical aerosols, pharmaceutical or industrial coatings, as well as devices such as humidifiers.
Evenly distributed and small droplet size is also important for coating applications (including adhesives). Fine particle sizes permit uniform coating thickness and even exposure to ambient air, allowing even curing of the coating or adhesive.
The spray configuration in conventional fuel injectors or atomizers typically consists of one or more jets or streams aimed outwards from the injector. However, this configuration is limited, and often results in impaction of liquids on the intake manifold and intake port walls, causing a film to form which needs to be accounted for in transient fueling calculations.
An approach to effective atomization is the use of high pressure liquid injection and small orifices, but high pressure systems have increased parasitic drag, in the form of added power required to drive the pump to higher pressures, are typically more expensive and prone to failure, and small orifices are typically prone to clogging.
Also an approach to effective atomization is to use air shear with the liquid, where high pressure fast moving air is used to shear the liquid stream to achieve atomization. This approach has its own limitations in terms of breaking the liquid droplets. In addition, pressurized air must be provided by a secondary system and is most often supplied via a mechanically driven or electrically driven pump, which imposes high parasitic drag on the engine.
Colliding jets of liquid are known to provide good atomization. See N. Ashgriz, “Colliding Jet Atomization,” in Handbook of Atomization and Sprays, N. Ashgriz (ed.), 2011, pp 685-707, http://dx.doi.org/10.1007/978-1-4419-7264-4_30.
Colliding jets are well known in liquid fueled rocket engines, as a means of mixing the fuel and the oxidizer together. Injectors for internal combustion engines differ from known rocket engine nozzles in that rocket engine nozzles are not metered devices, whereas injectors for internal combustion engines are designed to deliver, on command, a specific quantity of a liquid. This requires careful control of the flow rate over time, which is traditionally achieved via a solenoid, but can also be controlled via hydraulic pilot actuation, hydraulic amplification, piezo-electric stack, pneumatic means, or other methods.
In one embodiment, disclosed is an insert for a fluid nozzle that produces an atomized liquid. In an embodiment, the nozzle and the insert may be cylindrical in shape or cylindrical-like in shape. Regardless of the shape, in an embodiment, a pressurized source of a liquid provides the liquid that is fed to the nozzle, wherein a body of the nozzle has a liquid inlet at a proximal end and a liquid outlet at a distal end. The body of the nozzle may have a generally circular cross section with a central longitudinal axis, and may include a center cavity within the nozzle in which the insert is located. The insert may have the same central axis of symmetry and longitudinal axis as the body of the nozzle. The insert may have a proximal end and a distal end. Two or more passages may pass through the insert (in one example, each passage has substantially the same diameter “d” and each passage is substantially uniform in cross-section). Each passage may terminate at the distal end of the insert. The insert may be housed within the body of the nozzle such that the insert passages at the distal end of the insert (and at the distal end of the body of the nozzle) are exposed from the distal end of the body of the nozzle. Each insert passage may be arranged such that it is aligned with another (or others) to form a “colliding set” with an included angle. Fluid jets exiting the distal end of the insert through each passage substantially impinge on one another at a specified point (which is a specific position away from the exits of the passages). Pressurized liquid may be forced from the proximal end of the nozzle, through the center cavity of the nozzle, to the insert. The liquid may enter into contact with the insert, which may guide the flow of liquid to the insert passages (wherein the liquid may then flow through the passages to direct jets of the pressurized liquid out of the distal end of the nozzle at a focal point that is external to the insert). The substantial impingement of pressurized liquid jets at the focal point, or points, creates an atomized form of the liquid.
The insert may be housed within a nozzle that does not have a cylindrical exterior form, or may be housed in a unit containing several nozzles (within each of which nozzles may be housed a respective insert).
The insert may be connected to a nozzle having a valving means for providing a precise quantity of liquid flow at a precise start time and a precise stop time.
An insert may be housed in one or more nozzles which may inject the fluid into one or more ports, or any location in the air intake track(s) or exhaust track(s), for application in an internal combustion engine.
In one embodiment, the insert may be useful for a multitude of fluids, such as liquid fuels, oxidizers, fuel-alcohol blends (including Ethanol blends ranging from E0 to E100), water, salt, urea, adhesive, finish coatings, paint, lubricants or any solutions or mixtures.
In one embodiment, the insert may be constructed of any grade of steel, aluminum, brass, copper, alloys, composites (including graphite, ceramic, carbon or fiber blends), or a multitude of plastic chemistries.
In one embodiment, the insert may comprise a range of features and geometries including a range of cylindrical dimensions (with a minimum height of X and a minimum outer diameter of Y); a quantity of orifice passage holes which may have a minimum quantity of two holes; a range of orifice hole diameters, which may have a minimum size of 100 um; one or more “colliding sets” of passages; a range of included angles which may have a minimum angle of 40 degrees and a maximum angle of 160 degrees; and one or more “colliding jet” focal points (such a “colliding jet focal point” refers to a focal point at which ejected fluid from a “colliding set” of passages meet).
The aforementioned insert may be pressed or welded into an outer nozzle, or may be threaded and fastened into an outer nozzle, or may be captured by an inner plug within the outer nozzle, or may be captured by a spring within the inner nozzle, or may be pinned transversely into the outer nozzle, or may be held within the outer nozzle with an annular clip.
These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings (some of the drawings are not drawn to scale and some of the drawings are drawn at the indicated scale; further, where scale and/or dimensions are provided, they are provided as examples only) wherein:
In one embodiment, an insert is provided for a liquid injection nozzle. The liquid may be for injection into reciprocating, or rotary, internal combustion engines. Such liquids may be fuels, water, or aqueous solutions. The insert may be housed within a nozzle. The insert may have a plurality of passages that emit at least two jets of the liquid (under pressure) aimed at an impingement point. The jets of liquid may substantially impinge on each other. The collision of the jets at the impingement point(s) efficiently atomizes the liquid.
Compressed liquids, such as water or liquid fuels, possess a specific potential energy, or SPE (in units of kJ/kg), where SPE=ΔP/ρ, where ΔP is the pressure drop across a fuel nozzle in kN/m2, and ρ is liquid density in kg/m3. Thus, for water at 10 bar pressure difference and density of 1000, SPE=1 kJ/kg. When expanded ideally this will result into a jet velocity of v=(2ΔP/ρ)½=(200) ½=100 m/s. When two or more such jets collide some of this kinetic energy is converted into heat, causing a portion of the liquid to evaporate, thus creating a very powerful additional mechanism of disintegration (besides shear and turbulence disintegration mechanisms). As compared to water, which has the largest latent heat, other liquid fuels, such as gasoline or alcohols, will exhibit a significantly improved atomization at significantly less pressures and higher orifice diameters.
In one embodiment, the theoretical velocity V (or speed) of the liquid jet coming out of the nozzle is greater than 10 m/s. In other examples, V may be 20 m/s, 30 m/s, 50 m/s, 75 m/s, 100 m/s or greater.
In various embodiments, provided are superior atomization, shorter liquid spray length and finer droplet sizes (relative to certain conventional liquid spray nozzles). In one specific example, the sharp inward angle of the jets (which allows the jets to impinge substantially upon one another a short distance from the exit of the passage) provided by the configuration of liquid passages in the insert, result in substantial improvements in both atomization and liquid length over non-impinging conventional techniques (thereby providing very efficient atomization in close proximity to the exit face of the passages). These improvements are due at least in part to the impact force being proportional to the normal force the jets make relative to one another. With respect to such normal force, see
Further, in a nozzle according to an embodiment there is no metering or actuation so device size, flow rate, and packaging are much less constrained than a metered device.
In an embodiment, an apparatus comprises a nozzle insert that produces an atomized liquid. The apparatus may further comprise a pressurized source of a liquid which feeds the liquid to a nozzle in which is housed the insert. The body of the nozzle may have a liquid inlet and a liquid outlet, wherein the nozzle housing is cylindrical in shape. The nozzle housing may have a cavity within, wherein the insert is located downstream of the nozzle liquid inlet, and upstream of the nozzle outlet. The insert may have a generally circular cross section with a central axis. The insert may be aligned on the same longitudinal central axis as the nozzle. The insert may have a proximal end and a distal end, wherein two or more passages pass through the insert. Each passage may originate from a location between the insert proximal and distal ends and may terminate at the distal end of the insert. The passages may be arranged such that each is aligned with one or more others to form an included angle, and the passages may provide for fluid jets exiting the distal end to substantially impinge on one or more others at a specified distance away from the distal end of the insert (e.g., along the central longitudinal axis of the insert). Pressurized liquid is forced through the nozzle, and consequently to the insert housed within the nozzle. The liquid flows around or through the insert to the passages at the distal end of the insert, where each passage passes through the insert to direct a jet of the pressurized liquid out of the distal end at a focal point (see, e.g., focal point F1 in
Various embodiments are characterized by a plurality of passages (or holes) through the distal end of the insert. There may be two or more such passages (the passages may be of the same diameter or different diameters). The passages may form “colliding sets” of two or more passages (e.g., of the same diameter), wherein such colliding sets may be characterized by the included angle formed by the passages of the “colliding set”.
Referring now to
See also
Referring now to
In an embodiment, the insert is held within the outer nozzle housing and is seated against an annular surface within the outer nozzle housing (see arrow “A” in
Referring now to
Referring now to
Referring now to
Referring now to
In another embodiment (see, for example,
Referring now more particularly to
In another embodiment, the nozzle housing has a single central inlet through which liquid flows, the nozzle housing has a single central outlet through which the insert is exposed, and fluid flow exits the nozzle insert.
In another embodiment, the insert is not materially connected to the nozzle housing and is in close proximity to the nozzle housing distal end.
In various embodiments, the number of fluid passages may be 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, 8 or more, 9 or more, 10 or more, 11 or more, 12 or more, 13 or more, or 14 or more.
In various embodiments, the included angle formed by two or more fluid passages ranges from about 40 degrees to about 160 degrees. In other embodiments, the included angle is between about 90 degrees and about 130 degrees. In other embodiments, the included angle may be equal to or greater than about 40 degrees, about 45 degrees, about 50 degrees, about 60 degrees, about 70 degrees, about 80 degrees, about 90 degrees, about 100 degrees, about 110 degrees, about 120 degrees, about 130 degrees, about 140 degrees, about 150 degrees, or about 160 degrees.
In various embodiments, the pressure applied to the liquid that is supplied to insert via the nozzle housing may range from about 0 psi to about 500 psi or greater. For example, the pressure may be up to about 5 psi, about 10 psi, about 15 psi, about 20 psi, about 25 psi, about 30 psi, about 40 psi, about 50 psi, about 60 psi, about 70 psi, about 80 psi, about 90 psi, about 100 psi, about 150 psi, about 200 psi, about 250 psi, about 300 psi, about 350 psi, about 400 psi, about 450 psi, about or about 500 psi or greater, or any value therebetween.
In one embodiment, the fluid is a volatile fuel of any gasoline-alcohol blends including (but not limited to): E0, E5, E10, E15, E20, E25, E30, E35, E40, E50, E60, E70, E75, E85, E90, E95, E96, E97, E98, E99, and E100.
In another embodiment, the liquid is water.
In another embodiment, the liquid is water and an alcohol, or any mixture thereof.
In another embodiment, the liquid is water and salt, or any mixture thereof.
In another embodiment, the liquid is water and urea, or any mixture thereof.
In an embodiment, the insert is constructed from one or more of: a grade of stainless steel, a grade of steel, a grade of aluminum alloy, a grade of brass, a grade of copper and its alloys, a grade of plastic, a grade of graphite, and/or any combination thereof.
In another embodiment, each passage of a “colliding set” of two or more passages are of different hole diameters.
In another embodiment, a plurality of “colliding sets” of two or more passages are present, each of the “colliding sets” share the same focal point, and each of the “colliding sets” have different included angles and are located at different “virtual circles” In this regard, see, for example,
In another embodiment, a plurality of “colliding sets” of two or more passages are present, each of the “colliding sets” have a specific focal point different than the other, and each of the “colliding sets” has the same included angle and is located at different virtual circles.
In another embodiment, a plurality of “colliding sets” of two or more passages are present, each of the “colliding sets” have a specific focal point different than the other, and each of the “colliding sets” has different included angles and is located at the same virtual circle.
In another embodiment, a plurality of “colliding sets” of two or more passages are present, each of the “colliding sets” have a specific focal point different than the other, and each of the “colliding sets” has different included angles and is located at different virtual circles.
In another embodiment, the insert is cylindrical in shape and has a maximum outer diameter ranging from about 2 mm to about 45 mm. For example, the maximum outer diameter may be equal to about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 11 mm, about 12 mm, about 13 mm, about 14 mm, about 15 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm or about 45 mm or greater.
In another embodiment, each passage is of about uniform cross section with a diameter “d”. The diameter may range from about 80 um to about 1000 um or greater. For example, the diameter may be about 80 um, about 90 um, about 100 um, about 110 um, about 120 um, about 130 um, about 140 um, about 150 um, about 160 um, about 170 um, about 180 um, about 190 um, about 200 um, about 210 um, about 220 um, about 230 um, about 240 um, about 250 um, about 260 um, about 270 um, about 280 um, about 290 um, about 300 um, about 310 um, about 320 um, about 330 um, about 340 um, about 350 um, about 360 um, about 370 um, about 380 um, about 390 um, about 400 um, about 500 um, about 600 um, about 700 um, about 800 um, about 900 um, about or 1000 um or greater. In one specific example, the diameter is about 100 um to about 600 um. In another specific example, the diameter is about 200 um to about 450 um.
In another embodiment, each fluid passage is arranged such that it is aligned with one or more others to form an included angle, wherein each fluid jet exiting the distal end substantially impinges on one or more others, at a specified distance away from the distal end of the insert, along a central Z axis of the nozzle body (wherein the jets form a “colliding set of jets”).
In another embodiment, the insert and/or nozzle may be made by electrical discharge machining (EDM) and/or spark machining.
Referring now to
As seen in
In other embodiments, the disclosed nozzle assemblies may be used to deliver: (a) coffee or other beverages; (b) water, such as in the context of delivering water into an engine; and/or (c) adhesives.
In another embodiment, a valving means (or metering means) is not part of the disclosed nozzle assemblies.
In another embodiment, a valving means (or metering means) is not part of the disclosed inserts.
In another embodiment, a valving means (or metering means) is part of the disclosed nozzle assemblies.
In another embodiment, a valving means (or metering means) is part of the disclosed inserts.
As described herein, in one embodiment, the liquid jet collision is accomplished via a single nozzle (instead of by use of two or more separate nozzles).
As described herein, in one embodiment, the liquid jet collision is intended for liquid break up (instead of for mixing of two different liquids).
As described herein, in one embodiment, the liquid jet collision comprises colliding liquid streams against one another (instead of against a solid object).
As described herein, in one embodiment, the liquid jet collision relies on converging passages, and allows for the creation of sprays that emerge at an angle to the normal line of the nozzle.
The described embodiments of the present invention are intended to be illustrative rather than restrictive, and are not intended to represent every embodiment of the present invention. Various modifications and variations can be made without departing from the spirit or scope of the invention as set forth in the following claims both literally and in equivalents recognized in law.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2016/068200 | 12/22/2016 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62270882 | Dec 2015 | US |
