Abstract:
The present invention provides methods and apparatus for premixing fuel and oxidant for combustion. The methods and apparatus may include a two stage vortex, each stage accommodating different flow rate ranges. The vortex pulverizes fuel and optimally mixes the fuel with an oxidant prior to introduction into a combustion chamber. The premixing results in more complete combustion and, consequently, fuel efficiency may be increased and pollution may be decreased. The present invention also enables introduction of fuel and oxidant to an engine without creating any shockwaves in engine cylinders, which may otherwise occur with current fuel injection systems.

Description:
BACKGROUND OF THE INVENTION 
   Many types of devices have been developed over the years for the purpose of converting liquids or aerosols into gas-phase fluids. Many such devices have been developed, for example, to prepare fuel for use in internal combustion engines. To optimize fuel oxidation within an engine&#39;s combustion chamber, the fuel/air mixture commonly must be further vaporized or homogenized to achieve a chemically-stoichiometric gas-phase mixture. Ideal fuel oxidation results in more complete combustion and lower pollution. 
   More specifically, relative to internal combustion engines, stoichiometricity is a condition where the amount of oxygen required to completely burn a given amount of fuel is supplied in a homogeneous mixture resulting in optimally correct combustion with no residues remaining from incomplete or inefficient oxidation. Ideally, the fuel should be completely vaporized, intermixed with air, and homogenized prior to entering the combustion chamber for proper oxidation. Non-vaporized fuel droplets generally do not ignite and combust completely in conventional internal and external combustion engines, which presents problems relating to fuel efficiency and pollution. 
   Incomplete or inefficient oxidation of fuel causes exhaustion of residues from the internal or external combustion engine as pollutants, such as unburned hydrocarbons, carbon monoxide, and aldehydes, with accompanying production of oxides of nitrogen. To meet emission standards, these residues must be dealt with, typically requiring further treatment in a catalytic converter or a scrubber. Such treatment of these residues results in additional fuel costs to operate the catalytic converter or scrubber. Accordingly, any reduction in residues resulting from incomplete combustion would be economically and environmentally beneficial. 
   Aside from the problems discussed above, a fuel-air mixture that is not completely vaporized and chemically stoichiometric causes the combustion engine to perform at less than peak efficiency. A smaller portion of the fuel&#39;s chemical energy is converted to mechanical energy when fuel is not completely combusted. Fuel energy is wasted and unnecessary pollution is created. Thus, by further breaking down and more completely vaporizing the fuel-air mixture, better fuel efficiency may be available. 
   Many attempts have been made to alleviate the above-described problems with respect to fuel vaporization and incomplete fuel combustion. In automobile engines, for example, direct fuel injection has almost universally replaced carburetion for fuel delivery. Fuel injectors spray a somewhat fine fuel mist directly into the cylinder of the engine and are controlled electronically. Currently, it is believed by most that the fuel injector spray allows the fuel and air to mix in the cylinders more efficiently than carburetion. Nevertheless, the fuel droplet size of a fuel injector spray is not optimal and there is little time for the fuel to mix with air prior to ignition. Even current fuel injector systems do not fully mix the fuel with the necessary air. 
   Moreover, it has been recently discovered that fuel injector sprays are accompanied by a shockwave in the fuel spray. The shockwave may prevent the fuel from fully mixing with air. The shockwave appears to limit fuel mass to certain areas of the piston, limiting the fuel droplets&#39; access to air. 
   Other prior systems have also been developed in attempts to remedy the problems related to fuel vaporization and incomplete fuel combustion. For example, U.S. Pat. Nos. 4,515,734, 4,568,500, 5,512,216, 5,472,645, and 5,672,187 disclose various fuel vaporizing devices. 
   Nevertheless, prior vaporization devices fail to provide a configuration which is large enough to attain volumetric efficiencies at high RPM&#39;s, yet small enough to get high resolution responses at lower RPM&#39;s. Indeed, the prior devices have generally had to choose between volumetric efficiency at high RPM&#39;s and high resolution response at lower RPM&#39;s. 
   SUMMARY OF THE INVENTION 
   The principles described herein may address some of the above-described deficiencies and others. Specifically, some of the principles described herein relate to liquid processor apparatuses and methods. 
   One aspect provides a method comprising fueling an internal combustion engine. The fueling comprises creating a gaseous, homogenous premixture of fuel and oxidizer in a first pre-combustion vortex chamber and drawing the gaseous, homogenous premixture of fuel and oxidizer from the first pre-combustion vortex chamber into a combustion chamber. The method may further comprise preventing shockwaves in the combustion chamber. The shockwaves may be prevented in the combustion chamber upon the drawing of the gaseous, homogenous premixture of fuel and oxidizer from the first pre-combustion vortex chamber. 
   According to some aspects, creating a gaseous, homogenous premixture of fuel and oxidizer comprises creating an oxidizer vortex in the first pre-combustion vortex chamber, introducing fuel at an axis of the oxidizer vortex, and pulverizing the fuel and mixing the fuel with the oxidizer at an axial area of the first pre-combustion vortex chamber. Creating an oxidizer vortex may comprise introducing the oxidizer into the first pre-combustion vortex chamber at a non-tangential, non-radial angle through multiple fluid passageways. The method may include directing the gaseous, homogenous premixture evenly into a plurality of intake passages. 
   According to some aspects, creating a gaseous, homogenous premixture of fuel and oxidizer comprises creating an oxidizer vortex in the first pre-combustion vortex chamber, centering the oxidizer vortex on a intake tower, introducing fuel at an axis of the oxidizer vortex, and pulverizing and mixing the fuel with the oxidizer. 
   According to some aspects, creating a gaseous, homogenous premixture of fuel and oxidizer comprises providing a primary stage oxidizer introduction path, providing a secondary stage oxidizer introduction path, opening a valve in the secondary stage oxidizer introduction path upon reaching a predetermined oxidizer requirement threshold, creating an oxidizer vortex in a second pre-combustion vortex chamber with fluid flow from the secondary stage oxidizer introduction path, introducing fuel at an axis of the oxidizer vortex, and pulverizing and mixing the fuel with the oxidizer. When the predetermined oxidizer requirement threshold is met, a valve in the primary stage oxidizer introduction path remains fully open and a valve in the secondary stage oxidizer introduction path is also opened. 
   According to another aspect, creating a gaseous, homogenous premixture of fuel and oxidizer comprises creating an oxidizer vortex in a second pre-combustion vortex chamber, centering the oxidizer vortex on a diverging intake tower having a lip, introducing fuel at an axis of the oxidizer vortex, and pulverizing and mixing the fuel with the oxidizer. Fuel may be introduced both axially and radially through an injector at the axis of the oxidizer vortex. 
   According to another aspect, creating a gaseous, homogenous premixture of fuel and oxidizer comprises providing a primary stage oxidizer introduction path, providing a secondary stage oxidizer introduction path, mechanically opening a throttle valve in the second stage oxidizer introduction path according to fuel pedal position, creating an oxidizer vortex in a second pre-combustion vortex chamber with fluid flow from the secondary stage oxidizer introduction path, introducing fuel at an axis of the oxidizer vortex, and pulverizing the fuel and mixing the fuel with the oxidizer. 
   Another aspect comprises heating the gaseous, homogenous premixture of fuel and oxidizer with a water jacket. 
   One embodiment provides an apparatus comprising a pre-combustion fuel mixing device. The device further comprises a housing, a first pre-combustion vortex chamber enclosed by the housing, a plurality of angled passages leading into the first pre-combustion vortex chamber for creating a vortex, a first oxidant fluid flow path in fluid communication with the first pre-combustion vortex chamber, and a second pre-combustion vortex chamber enclosed by the housing and aligned axially with the first pre-combustion vortex chamber. The second pre-combustion vortex chamber may be larger than the first pre-combustion vortex chamber. The device may comprise a plurality of angled passages leading into the second pre-combustion vortex chamber for creating a vortex, and a second oxidant fluid flow path in fluid communication with the second pre-combustion vortex chamber. The angled passageways may be non-tangential and non-radial. 
   One embodiment of the device further comprises first and second diverging nozzles leading out of the first and second pre-combustion vortex chambers, respectively. The first diverging nozzle may comprise a plurality of lateral passages angled opposite of the plurality of angled passages leading into the first pre-combustion vortex chamber. 
   One embodiment comprises a conical pillar adjacent to an outlet of the first and second pre-combustion vortex chambers. The conical pillar may comprising a peripheral lip. 
   One embodiment of the device further comprises a valve disposed in the second oxidant fluid flow path, wherein the valve operates and opens a predetermined amount based on oxidant need. The device may comprise a throttle body housing a valve. The valve controls fluid flow through the second oxidant fluid flow path. The valve may be mechanically connected to a fuel pedal. 
   One embodiment of the device comprises a fuel injector aligned substantially axially with the first and second pre-combustion vortex chambers, the fuel injector comprising an axial flow channel, and a plurality of radial flow channels. The fuel injector may be disposed in a cylindrical cavity of the housing and in fluid communication with the first and second pre-combustion vortex chambers. The fuel injector may comprise a liquid flow channel and an atmospheric vent in fluid communication with liquid flow channel. 
   According to one embodiment, the first pre-combustion vortex chamber is defined by a wheel, the wheel having the angled passages, wherein the angles of the angled passages are non-tangential, and non-radial. The angles of the angled passages may be at least about thirty degrees from tangent. 
   According to one embodiment, the first and second pre-combustion vortex chambers are defined by first and second wheels, the wheels having the angled passages. The second wheel comprises a radius at least twice as large as the first wheel. The angles of the angled passages may range between ten and seventy degrees from tangent. 
   Another embodiment comprises an internal combustion engine premixing device. The device comprises a two stage vortex chamber, and the first stage is in fluid communication with a first oxidation source. A second stage is in fluid communication with a separate, second oxidation source. The device comprises a fuel injector arranged axially internal of the first and second stages. The first stage, the second stage, and the fuel injector may be substantially coaxial. In one embodiment the first stage may comprises a high vacuum, low flow rate vortex chamber, and the second stage may comprise a larger volume than the first stage and include a low vacuum, high flow rate vortex chamber. A “low” flow rate refers to a mass flow rate of less than approximately 262 lbm/hr. A “high” flow rate refers to a mass flow rate of more than approximately 262 lbm/hr. The first stage may comprise a first wheel having angled passages for creating a vortex, and the second stage may comprises a second wheel that is larger than the first wheel for creating a vortex. 
   Some embodiments of the apparatus comprise a first nozzle disposed at an outlet to the first stage, the first nozzle comprising fluid passages arranged both in a vortex direction and in a direction opposite of the vortex direction, for directing fluids pulverized by the first stage in a generally non-rotational flow. 
   Some embodiments comprise a diverging nozzle at an outlet of the second stage. Some embodiments include a pillar arranged adjacent to the internal combustion engine premixing device for centering a vortex created in the first or second stages. According to some embodiments, the fuel injector comprises axial and radial ports for injecting fuel into the first and second stages. According to some embodiments, the device is infinitely adjustable between oxidant fluid flow directed to the first and second stages. According to some embodiments, the first oxidation source is open to the first stage until a predetermined flow rate is reached, and the second oxidation source is opened when the predetermined flow rate is reached. Some embodiments of the device further comprise a water jacket disposed about the two stage vortex chamber. 
   Another aspect provides a method of mixing fuel with an oxidant. The method comprises axially introducing fuel into an oxidant vortex, and atomizing the fuel and mixing the fuel with the oxidant vortex. 
   Another aspect provides a method comprising fueling an automobile. The method includes premixing fuel with an oxidant and drawing the premixed fuel and oxidant into a combustion chamber of the automobile by vacuum without forcing additional fuel into the combustion chamber. The premixing comprising introducing fuel into an oxidant vortex to create premixed fuel and oxidant. 
   According to one aspect, the premixing comprises providing first and second vortex chambers in series. The oxidant enters the first and second vortex chambers at an angle and creates the oxidant vortex. The premixing may also comprise providing a fuel injector and injecting fuel axially, such that the injecting injects fuel axially into the oxidant vortex created by either one of the first or second vortex chambers. 
   According to some aspects, the premixing comprises centering and holding the oxidant vortex. According to some aspects, the drawing comprises evenly distributing the premixed fuel and oxidant into a manifold. 
   One embodiment provides an apparatus comprising a fuel/air mixer. The fuel/air mixer comprises a housing and an axially aligned vortex assembly. The vortex assembly comprises a hat comprising a cylindrical cavity. The vortex assembly also comprises a fuel injector disposed in the cylindrical cavity, the fuel injector comprising an axial fuel flow path and a plurality of radial fuel flow paths. The vortex assembly also comprises an annulus between the cylindrical cavity and the injector at the radial fuel flow paths. The vortex assembly also comprises a first vortex wheel arranged adjacent to the hat, the first vortex wheel comprising a plurality of angled passages spaced around a periphery of the first vortex wheel, the angled passages comprising an angle ranging between approximately five and fifty degrees from tangent. The vortex assembly may further comprise a first output nozzle comprising a rim, the rim contacting the first vortex wheel, the first output nozzle further comprising a primary central axis hole open to the center of the first vortex, and a plurality of angled passages extending through the nozzle at different angles, the different angles directing flow both clockwise and counterclockwise. The vortex assembly may comprise a restrictor plate spaced from the first output nozzle and a second vortex wheel in contact with the restrictor plate. The second vortex wheel is larger than the first vortex wheel, and the second vortex wheel comprises a plurality of angled passages spaced around a periphery of the second vortex wheel. The angled passages comprise an angle ranging between approximately five and fifty degrees from tangent. The vortex assembly may include a second output nozzle adjacent to the second vortex wheel and leading out of the housing. 
   According to some embodiments, the apparatus may further comprise a first oxidizer passageway disposed in the housing and in fluid communication with the first vortex wheel, the first oxidizer passageway comprising a first adjustable valve. The apparatus may also include a second oxidizer passageway disposed in the housing and in fluid communication with the second vortex wheel. According to some embodiments, flow through the first or second oxidizer passageways is mutually exclusive. 
   According to some embodiments, the apparatus further comprises a first oxidizer passageway disposed in the housing and in fluid communication with the first vortex wheel, the first oxidizer passageway comprising a first electronically adjustable valve. The apparatus may also include a second oxidizer passageway disposed in the housing and in fluid communication with the second vortex wheel, the second oxidizer passageway comprising a mechanically operated butterfly valve operatively connected to a fuel pedal. 
   Another aspect provides a method of fueling an automobile, the method comprising premixing fuel with air and automatically varying an air-to-fuel ratio based on engine speed and load. In one embodiment, the premixing comprises introducing fuel into an air vortex to create a premixture of fuel and air. In one embodiment automatically varying the air-to-fuel ratio comprises varying the air-to-fuel ratio according to parameters of a lookup table. In one embodiment, automatically varying the air-to-fuel ratio comprises varying the air-to-fuel ratio according to parameters of a lookup table having engine speed and manifold absolute pressure as table variables. In one embodiment, automatically varying the air-to-fuel ratio comprises varying the air-to-fuel ratio to between approximately 0.97 and 1.3 of a stoichiometric ratio. That is to say, varying the air-to-fuel ratio to a ratio between approximately 14.2:1 and 19:1. In some embodiments, the air-to-fuel ratio is varied between 12.0:1 and 21:1 or between 13.0:1 and 20:1. In one embodiment, automatically varying the air-to-fuel ratio comprises setting the air-to-fuel ratio below a stoichiometric ratio at an engine intake manifold absolute pressure above approximately 80 KPA abs . In one embodiment automatically varying the air-to-fuel ratio comprises setting the air-to-fuel ratio above a stoichiometric ratio at an engine intake manifold absolute pressure below approximately 80 KPA abs . In one embodiment, automatically varying the air-to-fuel ratio comprises setting the air-to-fuel ratio approximately 1.12 times greater than a stoichiometric ratio at an engine intake manifold absolute pressure of approximately 60 KPA abs . In one embodiment, automatically varying the air-to-fuel ratio comprises setting the air-to-fuel ratio approximately 1.21 times greater than a stoichiometric ratio at an engine intake manifold absolute pressure of approximately 50 KPA abs . In one embodiment, automatically varying the air-to-fuel ratio comprises setting the air-to-fuel ratio approximately 1.27 times greater than a stoichiometric ratio at an intake manifold absolute pressure of approximately 42 KPA abs  or less and engines speeds of 1000 RPM or less. In one embodiment, automatically varying the air-to-fuel ratio comprises setting the air-to-fuel ratio approximately 1.3 times greater than a stoichiometric ratio at an intake manifold absolute pressure of approximately 42 KPA abs  or less and engines speeds greater than 1000 RPM. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings illustrate certain embodiments discussed below and are a part of the specification. 
       FIG. 1  is a cross sectional view of a mixing apparatus in relation to an intake manifold according to one embodiment. 
       FIG. 2  is a perspective assembly view of a set of vortex creating components shown in  FIG. 1 , prior to enclosure within a housing. 
       FIG. 3  is a perspective view of the components shown in  FIG. 2  following assembly. 
       FIG. 4A  is a perspective view of an injection nozzle used in the mixing apparatus according to one embodiment. 
       FIG. 4B  is a cross sectional view of the injection nozzle shown in  FIG. 4A . 
       FIG. 5  is a perspective view of the mixing apparatus of  FIG. 1 . 
   

   Throughout the drawings, identical reference characters and descriptions indicate similar, but not necessarily identical elements. 
   DETAILED DESCRIPTION 
   Illustrative embodiments and aspects are described below. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, that will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. 
   As used throughout the specification and claims, the term “pre-combustion chamber” refers to an area that is not a combustion area. The words “including” and “having,” as used in the specification, including the claims, have the same meaning as the word “comprising.” 
   Turning now to the figures, and in particular to  FIGS. 1-5 , one embodiment of a mixing apparatus is shown. The mixing apparatus may comprise, for example, a pre-combustion fuel mixing device  100 . The pre-combustion fuel mixing device  100  may provide a premixed supply of fuel and oxidant to an internal combustion engine or other device.  FIG. 1  illustrates the pre-combustion fuel mixing device  100  fully assembled and in cross-section. 
   The pre-combustion fuel mixing device  100  comprises a housing  102 . The housing  102  is a generally rigid structure that may be made of metal, ceramic, composite, plastic, or other materials. The housing  102  encloses a number of internal components which are described below. The housing  102  is shown in perspective view in  FIG. 5 . The housing  102  may comprise any size or shape, although as shown in  FIG. 5 , some embodiments of the housing include an oxidant inlet section  104  and a vortex section  106 . The oxidant inlet section  104  may comprise a throttle body as shown in  FIG. 5 . 
   The housing  102  encloses a first pre-combustion vortex chamber or first stage  108 . The first pre-combustion vortex chamber  108  comprises a first axis  109 . A plurality of angled passages  110  lead into the first pre-combustion vortex chamber  108 . The plurality of angled passages  110  facilitate the creation of a vortex or tornado in the first pre-combustion vortex chamber  108 . A first oxidant flow introduction path  112  disposed in the housing  102  is in fluid communication with the first pre-combustion vortex chamber  108 . The first oxidant flow path  112  provides a primary air or oxidant source to the first pre-combustion vortex chamber  108 . A set of arrows  114  indicates the direction of the flow of air or other oxidant through the first oxidant flow introduction path  112  into the first pre-combustion vortex chamber  108 . A first valve  116  disposed in the first oxidant flow path  112  may comprise an electronically controlled valve to regulate the flow or flow rate of air into the first pre-combustion vortex chamber  108  based on need. 
   The plurality of angled passages  110  leading into the first pre-combustion vortex chamber  108  may comprise slots formed in and spaced around a periphery of a wheel such as first vortex wheel  118 . The first vortex wheel  118  is most clearly shown in perspective view in  FIG. 2 . The first vortex wheel  118  may comprise a generally rigid structure and may be made of metal, plastic, ceramic, composite, or other materials. The first vortex wheel  118  is coaxial with first axis  109 . The angled passages  110  of the first vortex wheel  118  may be non-tangential, and non-radial. That is to say, the angled passages  110  comprise an angle from tangent greater than zero degrees and less than ninety degrees (ninety degrees is perfectly radial or centered). The angled passages  110  may be angled between about ten and seventy degrees. The angled passages  110  may range between about five and fifty degrees. The angled passages  110  may be at least about thirty degrees from tangent. Thus, the angled passages  110  tend to facilitate creation of a vortex in the first pre-combustion vortex chamber  108  as air is introduced therein. The vortex tends to be spaced internal of the first wheel  118 , as the angled passages  110  are non-tangential. 
   According to one embodiment, the first vortex wheel  118  is adjacent to and in contact with a hat  120 . The hat  120  is generally circular and attached to the housing  102 . The hat  120  may be semi-spherical or dish shaped and extend partially into the center of the first vortex wheel  118 . For example, a spherical portion  122  of the hat  120  may extend approximately half way into the center of the first vortex wheel  118 . The hat  120  may comprise metal, plastic, ceramic, composite, or other material. As shown in  FIGS. 1-5 , the hat  120  may be coaxial with the first vortex wheel  118 . The hat  120  also includes a central hole  124  that may define a cylindrical cavity. The central hole  124  of the hat  120  is receptive of an injector, such as fuel injector  126 . 
   According to one embodiment, the fuel injector  126  may be coaxial with the first wheel and the hat  120 . The fuel injector  126  may include a flange  128  that connects the fuel injector  126  to the hat  120  and creates a seal. However, a head  130  of the fuel injector  126  inserts into the central hole  124  of the hat  120 . The diameter of the central hole  124  and the diameter of the head  130  of the fuel injector  126  are sized to leave an annulus  132  between an inner surface of the central hole  124  and an outer surface of the head  130 . The fuel injector  126  also includes a tail  134  that may extend outside of the housing  102 . The fuel injector  126  is in fluid communication with a fuel source. 
   According to one embodiment, the fuel injector  126  may include an inlet  135  and multiple fluid or liquid ports. For example, according to the embodiment of  FIGS. 4A-4B , the fuel injector  126  includes an axial flow channel  136  and a plurality of radial flow channels  138  each in fluid communication with the inlet  135 . According to the embodiment of  FIGS. 4A-4B , there are four equally spaced radial flow channels  138 . In addition, the fuel injector  126  may include one or more pressure equalization vents, such as atmospheric vents  140 . The atmospheric vents  140  may be open to atmosphere, and there may be one atmospheric vent  140  in fluid communication with each of the radial flow channels  138 . Therefore, according to  FIGS. 4A-4B , there are four atmospheric vents  140 . The atmospheric vents  140  prevent a pressure differential at the radial flow channels  138  and thus the axial flow channel  136 . 
   Returning to  FIGS. 1-2 , according to one embodiment the annulus  132  may provide a gap large enough to eliminate any flow restriction of fluids exiting the head  130  radially through the radial flow channels  138 . That is to say, the size or diameter of the radial flow channels  138  tends to limit flow capacity rather than the annulus  132 . The fuel injector  126  introduces fuel to the first pre-combustion vortex chamber  108  at the axis  109 , rather than through the angled passages  110 . 
   According to the embodiment of  FIGS. 1-5 , the first vortex wheel  118  is arranged adjacent to and may contact a first output nozzle  142 . The first output nozzle  142  is arranged coaxially with the first vortex wheel  118  and may comprise a diverging nozzle made of metal, plastic, ceramic, composite, or other material. The first output nozzle  142  may include a hemispherical hat  144  that extends partially into the first vortex wheel  118 . A lip  146  around the hemispherical hat  144  may provide a contact or resting surface for the first vortex wheel. The lip  146  may sit on an internal protrusion  147  of the housing  102 . Accordingly, the first output nozzle  142  may be suspended within the housing  102  as shown in  FIG. 1 . 
   According to one embodiment, the first output nozzle  142  comprises a central hole  148  that is open to the first pre-combustion vortex chamber  108 . In addition, the first output nozzle  142  includes a plurality of small angled passages extending laterally therethough at different angles. For example, according to the embodiment of  FIG. 2 , the first output nozzle  142  includes a first set of angled passages  150  in the hemispherical hat  144  and a second set of angled passages  150 ,  152  in a conical tail portion  154 . The first and second sets of angled passages  152  may include passages directing fluid in both clockwise and counter-clockwise directions. There may be any number of passages in the clockwise and counter-clockwise directions, and there may be a substantially equal number in each direction to create a non-vortical or non-rotational flow through the first output nozzle  142 . 
   According to one embodiment, the first output nozzle  142  leads to a second pre-combustion vortex chamber or second stage  158 . Together with the first pre-combustion vortex chamber  108 , the second pre-combustion vortex chamber forms a two stage vortex chamber. The second pre-combustion vortex chamber  158  may be coaxial with the first axis  109 . The second pre-combustion vortex chamber  158  is larger than the first pre-combustion vortex chamber  108  and may comprise a radius at least twice as large as the radius of the first pre-combustion vortex chamber  108 . A second plurality of angled passages  160  lead into the second pre-combustion vortex chamber  158 . The second plurality of angled passages  160  facilitate the creation of a vortex or tornado in the second pre-combustion vortex chamber  158 . A second or secondary oxidant flow introduction path  162  disposed in the housing  102  is in fluid communication with the second pre-combustion vortex chamber  158 . The secondary oxidant flow introduction path  162  is larger than the first oxidant flow introduction path  112 . The secondary oxidant flow path  162  provides air or another oxidant source to the second pre-combustion vortex chamber  158 . Arrows  164  indicate the direction of the flow of air or other oxidant into the second pre-combustion vortex chamber  158  and through the second set of angled passages  152  in the conical tail portion  154  of the first output nozzle  142 . A valve such as a second or butterfly valve  166  disposed in the second oxidant flow path  162  may comprise an electronically or mechanically controlled valve to regulate the flow rate of air into the second pre-combustion vortex chamber  158  based on need. The larger secondary oxidant flow path  162  and second pre-combustion vortex chamber  158  accommodate high fluid flow rates as needed. If mechanically controlled, the butterfly valve  166  may be connected by a cable  168  to a pedal or throttle such as a gas pedal  170  of an automobile. 
   According to one embodiment, the plurality of angled passages  160  leading into the second pre-combustion vortex chamber  158  may comprise slots formed in and spaced around a periphery of another wheel such as second vortex wheel  172 . The second vortex wheel  172  is most clearly shown in perspective view in  FIG. 2 . The second vortex wheel  172  may be larger—and according to some embodiments at least twice as large—as the first vortex wheel  118 . The second vortex wheel  172  may comprise a generally rigid structure and may be made of metal, plastic, ceramic, composite, or other materials. The second vortex wheel  172  is coaxial with the first axis  109 . The angled passages  160  of the second vortex wheel  172  may be non-tangential, and non-radial. The angled passages  160  comprise an angle from tangent greater than zero degrees and less than ninety degrees. The angled passages  160  may be angled between about ten and seventy degrees. The angled passages  160  may range between about five and fifty degrees. The angled passages  160  may be at least about thirty degrees from tangent. Thus, the angled passages  160  tend to facilitate creation of a vortex in the second pre-combustion vortex chamber  158  as air is introduced therein. The vortex tends to be spaced internal of the second wheel  172 , as the angled passages  160  are non-tangential. The second vortex wheel  172  may include a lid  174  with a central hole  176  open to the first output nozzle  142 , and a plurality of smaller holes  178 . A restrictor plate  156  may be disposed in the central hole  176 . The restrictor plate  156  may be curved or funneled as shown in the embodiment of  FIG. 2 . 
   According to one embodiment, the second vortex wheel  172  may rest on and may be attached to a closing plate  180 . The closing plate  180  may be substantially flush with the housing  102  and includes a central hole  182  coaxial with the first axis  109 . An inner ring  184  of the closing plate  180  may support a second or final outlet nozzle  186 . The second outlet nozzle  186  and the closing plate  180  may comprise generally rigid structures and may be made of metal, plastic, ceramic, composite, or other materials. The second outlet nozzle  186  may comprise an interior diverging nozzle as best shown in  FIG. 1 . The second outlet nozzle  186  may include a generally cylindrical outer portion  188  and an outer lip  190  having a diameter greater than the generally cylindrical portion  188 . The generally cylindrical outer portion  188  is sized to slide into the central hole  182  of the closing plate  180 , but the outer lip  190  limits the insertion depth. The outer lip  190  comprises a diameter that is larger than the diameter of the central hole  182 . According to one embodiment, the second outlet nozzle  186  straddles the closing plate  180  and extends partially into the interior of the second vortex wheel  172 . According to one embodiment, the first and second vortex chambers and one or more of the other components described above may comprise an axially aligned vortex assembly. 
   According to one embodiment, the second outlet nozzle  186  leads out of the pre-combustion fuel mixing device  100  and may provide a premixture of gaseous, homogenous fuel and oxidizer to a combustion chamber  192 . According to one embodiment, the pre-combustion fuel mixing device  100  is arranged adjacent to an intake manifold  194  that distributes the premixture of gaseous, homogenous fuel and oxidizer to several combustion chambers, such as internal combustion engine cylinders. Further, some embodiments include an intake pillar, such as a conical pillar  196 , at the second outlet nozzle  186 . The conical pillar  196  may be part of the intake manifold  194 . However, according to some embodiments the conical pillar  196  may also be part of and attached to the pre-combustion fuel mixing device  100 . 
   According to one embodiment, the conical pillar  196  is coaxial with the first axis  109 . The conical pillar  196  may be made of metal, plastic, ceramic, composite, or other materials. The conical pillar  196  may tend to center or hold the vortexes formed in either the first or second pre-combustion vortex chambers  108 ,  158 . Centering or holding the vortexes formed in either the first or second pre-combustion vortex chambers  108 ,  158  may aid in the pulverizing and mixing of the fuel into the premixture of gaseous, homogenous fuel and oxidizer. Centering the vortexes with the conical pillar  196  also tends to evenly distribute the premixture of gaseous, homogenous fuel and oxidizer into each of the various intake passageways of the intake manifold  194  leading to combustion chambers. 
   The conical pillar  196  may take on many forms. According to one embodiment, the conical pillar  196  comprises at least two different slopes. For example, a first conic surface  198  may have a first slope, and a second conic surface  200  may have a second slope steeper than the first slope. However, the conical pillar  196  may have a single slope according to one embodiment, and the second conic surface  200  may be replaced by a cylindrical surface according to some embodiments. As shown in the embodiment of  FIGS. 1-5 , the conical pillar  196  may comprise a peripheral lip  202  between the first and second conic surfaces  198 ,  200 . The peripheral lip  202  may provide a collection area for any liquids that fall out of the premixture of gaseous, homogenous fuel and oxidizer created by the vortexes. As the flow of gaseous, homogenous fuel and oxidizer passes by the conical pillar  196 , it tends to “drag” with it some of the liquids that collect at the peripheral lip  202 . 
   According to one embodiment, the housing  102  may define a heat exchanger such as a water cooling jacket  103 . The water cooling jacket  103  is in fluid communication with the cooling system of the engine and arranged around the first pre-combustion vortex chamber  108 . The water cooling jacket  103  comprises an internal fluid passageway of the housing  102  and may heat oxidant flowing through the first and second oxidant flow introduction paths  112 ,  162  and/or the premixture of gaseous, homogenous fuel and oxidizer. The water cooling jacket  103  primarily cools the engine and operates in steady state conditions at approximately 190-212° F. 
   According to some aspects, the pre-combustion fuel mixing device  100  facilitates methods of mixing fuel with oxidant. For example, some aspects provide methods of fueling an engine such as an internal combustion engine, or methods of fueling an automobile. According to one aspect, fuel is mixed with an oxidant by axially introducing fuel into an oxidant vortex. For example, fuel may be axially introduced into either or both of the first and second pre-combustion vortex chambers  108 ,  158  via the fuel injector  126 . Engine action creates a vacuum to draw air or other oxidant into one or both of the first and second pre-combustion vortex chambers  108 ,  158 . The arrangement of the angled passages  110 ,  160  into each of the first and second pre-combustion vortex chambers  108 ,  158  creates a vortex when air is drawn therein. Moreover, according to one embodiment, vortexes created in either of the first and second pre-combustion vortex chambers  108 ,  158  are held and centered by naturally attaching to the conical pillar  196 . 
   According to one embodiment, fuel is introduced axially (as opposed to tangentially or radially or laterally through circumferential slots such as the angled passages  110 ,  160 ) into the first and second pre-combustion vortex chambers  108 ,  158  to pulverize or atomize the fuel and create a gaseous, homogenous premixture of fuel and oxidizer. According to one embodiment, the pulverizing action is in an axial area spaced from the outer walls (at the angled passages  110 ,  160 ). 
   According to some embodiments, the gaseous, homogenous premixture of fuel and oxidizer is drawn from the first and/or second vortex chambers  108 ,  158  into the combustion chamber  192 . According to one embodiment, neither the fuel nor oxidant is injected or injected under pressure into the combustion chamber  192 . Instead, according to one embodiment, the premixture of fuel and oxidant is drawn into the combustion chamber  192  by vacuum (created, for example, by the reciprocation of a piston in a cylinder). Therefore, shockwaves that accompany typical fuel injection systems may be prevented in the combustion chamber  192 . Further, the premixture of fuel and oxidant drawn into the combustion chamber  192  by vacuum may be more likely to evenly distribute within the combustion chamber  192  to fill the vacuum. 
   According to some embodiments, the first chamber  108  operates either alone or in combination with the second vortex chamber  158 . For example, the butterfly valve  166  disposed in the second oxidant flow path  162  may be normally closed (but may allow a small amount of oxidant to leach thereby and enter, for example, the angled passages  152  of the first outlet nozzle  142 ). The valve  116  and the fuel injector  126  may be operated in electronic or mechanical coordination to provide a combustible ratio of fuel and oxidant based on need and/or engine speed. According to one embodiment, the first vortex chamber  108  comprises a high vacuum, low flow rate vortex chamber, and therefore the valve  116  is normally open when an engine needs a low flow rate of gaseous, homogenous fuel and oxidizer. The valve  116  may be infinitely adjustable to provide an appropriate amount of oxidant for introduced fuel. 
   According to one embodiment, when combustion needs require a higher flow rate of gaseous, homogenous premixture of fuel and oxidizer than the first oxidant flow path  112  can reasonably provide, the butterfly valve  166  may also open. For example, in one embodiment, the first oxidant flow path  112  can provide air mass flow rates ranging between approximately 0 and 262 lbm/hr. The second oxidant flow path  162  can provide higher flow rates of oxidant into the second pre-combustion vortex chamber  158  than the first oxidant flow path  112  can provide to the first pre-combustion vortex chamber  108 . Therefore, the second pre-combustion vortex chamber  158  may comprise a low vacuum, high flow rate vortex chamber. In one embodiment, the second oxidant flow path  162  can provide air mass flow rates ranging between approximately 0 and 1400 lbm/hr. In other embodiments, the second oxidant flow path  162  can provide air mass flow rates greater than 1400 lbm/hr. The butterfly valve  166  may also be infinitely adjustable to provide an appropriate amount of oxidant for introduced fuel. In one embodiment, the butterfly valve  166  is only opened after the valve  116  is fully open. Because the first and second pre-combustion vortex chambers  108 ,  158  are aligned axially in some embodiments, the same fuel injector  126  may provide fuel to both chambers. It will be understood by one of ordinary skill in the art having the benefit of this disclosure, however, that the ranges of flow rates mentioned above are exemplary in nature and the flow paths  112 ,  162  may be altered to provide other flow ranges as well. 
   According to one embodiment, flow through the first and second oxidant flow paths  112 ,  162  is additive. That is to say, when the valve  116  is fully open and additional flow capacity is necessary, the butterfly valve  166  is opened as well. For example, in one embodiment, the valve  116  may adjust flow rate between approximately 0 and 262 lbm/hr, and the butterfly valve  166  may be opened to increase flow rate capacity from 262 lbm/hr to 1400 lbm/hr or more. According to one embodiment, the butterfly valve  166  is mechanically connected to the gas pedal  170  of an automobile such that when the gas pedal is depressed to a predetermined level or a predetermined oxidizer requirement threshold is met, the valve  116  is fully open and the butterfly valve  166  opens. Nevertheless, according to one embodiment, the valve  116  and the butterfly valve  166  may each be only partially open. 
   According to one aspect, the pre-combustion fuel mixing device  100  is in operation with the valve  116  in the first oxidant flow introduction path or source  112  open. Oxidant enters the first pre-combustion vortex chamber  108  and creates a vortex. Fuel is introduced into the center of the vortex of the first pre-combustion vortex chamber  108 , which pulverizes the fuel and creates the gaseous, homogenous premixture of fuel and oxidizer. The gaseous, homogenous premixture of fuel and oxidizer passes through the first outlet nozzle  142 , through the second pre-combustion vortex chamber  108 , and out the second outlet nozzle  186 . According to some embodiments, which may include the conical pillar  196 , the flow of gaseous, homogenous premixture of fuel and oxidizer is evenly distributed though the intake manifold  194  and drawn under vacuum pressure into one or more combustion chambers  192 . 
   According to one aspect, the pre-combustion fuel mixing device  100  is in operation with the butterfly valve  166  in the second oxidant flow introduction path or source  162  open. Oxidant enters the second pre-combustion vortex chamber  158  and creates a vortex. Fuel is introduced into the center of the vortex of the second pre-combustion vortex chamber  158 , which pulverizes the fuel and creates the gaseous, homogenous premixture of fuel and oxidizer. The gaseous, homogenous premixture of fuel and oxidizer passes through the second outlet nozzle  186  and is evenly distributed though the intake manifold  194  and drawn under vacuum pressure into one or more combustion chambers  192 . 
   According to one aspect, the pre-combustion fuel mixing device  100  operates to fuel an automobile and varies an air-to-fuel ratio. For example, in one embodiment, the valves  116 ,  166  operate automatically (either electronically programmed or according to throttle position with a mechanical control) to vary air-to-fuel ratio based on engine speed and the load on the engine. In one embodiment, intake manifold absolute pressure is monitored, which is representative of the load on the engine. 
   In one embodiment, the automatic variation of the air-to-fuel ratio may follow parameters of a lookup table or a formula. Under some conditions, it is believed that a stoichiometric air-to-fuel ratio is ideal. However, some engine conditions may result in better fuel efficiency, more power, or other desired performance characteristics, at non-stoichiometric air-to-fuel ratios. The stoichiometric air-to-fuel ratio for gasoline is approximately 14.64:1. That is to say, a stoichiometric mixture of gasoline and air comprises 14.64 parts air for every one part gasoline. Nevertheless, according to some embodiments, the pre-combustion fuel mixing device  100  is operated to vary the air-to-fuel ratio. In one embodiment, the pre-combustion fuel mixing device  100  automatically varies the air-to-fuel ratio between approximately 14.2:1 and 19:1. In some embodiments, the air-to-fuel ratio is varied between 12.0:1 and 21:1. 
   For example, Table 1 below may be programmed into the valve controllers and/or the fuel injector of the pre-combustion mixture device  100  to vary the air-to-fuel ratio based on the engine speed and load (as indicated by the intake manifold absolute pressure). The values in Table 1 represent a multiplier from stoichiometric for the air-to-fuel ratio. For example, a value of 0.97 in Table 1 represents an air-to-fuel ratio of 14.2:1 (14.64×0.97), while a value of 1.3 represents an air-to-fuel ratio of 19:1 (14.64×1.3). 
   
     
       
             
           
             
             
           
             
             
             
             
             
             
             
             
             
           
             
             
             
             
             
             
             
             
             
           
         
             
               TABLE 1 
             
           
           
             
                 
             
             
               Air-to-Fuel ratio (as a function of stoichiometric) 
             
             
               for various engine conditions 
             
           
        
         
             
                 
               RPM 
             
           
        
         
             
               Load (KPa abs ) 
               200 
               1000 
               2000 
               3000 
               4000 
               5000 
               6000 
               7000 
             
             
                 
             
           
        
         
             
               10 
               1.27 
               1.27 
               1.30 
               1.30 
               1.30 
               1.30 
               1.30 
               1.30 
             
             
               42 
               1.27 
               1.27 
               1.30 
               1.30 
               1.30 
               1.30 
               1.30 
               1.30 
             
             
               50 
               1.21 
               1.21 
               1.21 
               1.21 
               1.21 
               1.21 
               1.21 
               1.21 
             
             
               60 
               1.12 
               1.12 
               1.12 
               1.12 
               1.12 
               1.12 
               1.12 
               1.12 
             
             
               70 
               1.04 
               1.04 
               1.04 
               1.04 
               1.04 
               1.04 
               1.04 
               1.04 
             
             
               80 
               1.00 
               1.00 
               1.00 
               1.00 
               1.00 
               1.00 
               1.00 
               1.00 
             
             
               90 
               0.97 
               0.97 
               0.97 
               0.97 
               0.97 
               0.97 
               0.97 
               0.97 
             
             
               105 
               0.97 
               0.97 
               0.97 
               0.97 
               0.97 
               0.97 
               0.97 
               0.97 
             
             
                 
             
           
        
       
     
   
   Those of ordinary skill in the art having the benefit of this disclosure will recognize that the values shown in Table 1 are exemplary in nature, and many other values may be used according to needs. Moreover, developing such a lookup table and/or generating a formula for air-to-fuel ratio variation might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. However, as shown in Table 1, at reduced loads, which may include highway cruising conditions, the air-to-fuel ratio tends to be increased, in some conditions to well above stoichiometric. At higher loads, on the other hand, the air-to-fuel ratio may be decreased, sometimes below stoichiometric. 
   The preceding description has been presented only to illustrate 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 disclosed. Many modifications and variations are possible in light of the above teaching. Such modifications are contemplated by the inventor and within the scope of the claims. The scope of the principles described is defined by the following claims.