Abstract:
A pulsed electrical charge or voltage may be applied to a pulsed fuel stream or combustion reaction supported by the fuel stream. The pulsed charge or voltage may be used to affect fuel mixing, flame trajectory, heat transfer, emissivity, reaction product mix, or other physical property of the combustion reaction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority benefit from U.S. Provisional Patent Application No. 61/760,631 filed 4 Feb. 2013 that, to the extent not inconsistent with the disclosure herein, is incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    Thermally produced NO x  (e.g., NO and NO 2 ) is one of the largest contributors to air pollution. Thus, NO x  reduction is an area of significant concern. Thermal NO x  is produced during combustion processes and does not form in significant concentrations until flame temperatures reach approximately 2700° F. 
         [0003]    Increased levels of NO in the atmosphere may cause various harmful environmental and health effects. In the atmosphere, NO is rapidly oxidized to NO 2 , which is an essential constituent in the formation of tropospheric ozone and photochemical smog. Additionally, NO 2  may be oxidized to form nitric acid, which may be deposited as acid rain. Moreover, NO x  may combine with other pollutants in the atmosphere to create ozone (O 3 ). 
         [0004]    New legislation on NO x  emissions has limited combustion system design. Many technologies have been designed in order to reduce NO x  emissions. For example, technologies that reduce flame temperature may also reduce flame stability or increase CO emissions. Thus, combustion system design has become an important field of study. 
         [0005]    NO x  generated in combustion processes may be reduced with either pre-combustion or post-combustion technologies. Post-combustion technologies break down NO x  emissions in the exhaust gases, while pre-combustion methods prevent the formation of NO x . Pre-combustion methods may include staging the combustion process and recirculating flue gases into the combustion process. 
       SUMMARY 
       [0006]    Embodiments disclosed herein are directed to a combustion system configured to generate and charge at least one series of fuel pulses, and related methods. In an embodiment, a combustion system includes a controller, a fuel control apparatus operatively coupled to the controller, at least one voltage source operatively coupled to the controller, and at least one fuel ionizer. The fuel control apparatus is configured to output a series of fuel pulses into a combustion volume responsive to control by the controller. The at least one voltage source is configured to output at least one series of high voltage pulses responsive to control by the controller. The at least one ionizer is configured to receive the at least one series of high voltage pulses and eject charges onto one or more of the at least one series of fuel pulses to charge the at least one series of fuel pulses. 
         [0007]    In an embodiment, a method for controlling a combustion reaction includes modulating a fuel control apparatus to output a series of fuel pulses, modulating an ionizer to apply charges to the series of fuel pulses, and supporting a combustion reaction with the series of charged fuel pulses. 
         [0008]    Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a diagram of a combustion system according to an embodiment. 
           [0010]      FIG. 2  is a flow chart of a method for operating a combustion system according to an embodiment. 
           [0011]      FIG. 3  is a diagram of a combustion system that may employ a pulsing mechanism and feedback control system for the generation of a flame according to an embodiment. 
           [0012]      FIG. 4  illustrates fuel staging process in which fuel packets may be injected into combustion chamber through a pulsing mechanism according to an embodiment. 
           [0013]      FIGS. 5A and 5B  illustrate waveforms according to different embodiments. 
           [0014]      FIG. 6  is an isometric cutaway view of an embodiment of a pulsing mechanism, which may include a rotative gate system to pulse fuel into combustion chamber. 
           [0015]      FIG. 7  is an isometric cutaway view of an embodiment of a pulsing mechanism, which may include a cylindrical gate system to pulse fuel into combustion chamber. 
           [0016]      FIG. 8  a diagram of an embodiment of a pulsing system including an arrangement of one or more Helmholtz resonators. 
           [0017]      FIG. 9  illustrates an embodiment of a pulsing system in which an insulator injector may be used for pulsing air and/or fuel. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    Embodiments disclosed herein are directed to a combustion system configured to generate and charge at least one series of fuel pulses, and related methods. In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. Other embodiments may be used and/or other changes may be made without departing from the spirit or scope of the disclosure. 
         [0019]      FIG. 1  is a diagram of a combustion system  100  according to an embodiment. The combustion system  100  includes a controller  102  and a fuel control apparatus  104 . The fuel control apparatus  104  is operatively coupled to the controller  102 . The fuel control apparatus  104  may be responsive to control by the controller  102  and output a series of fuel pulses  106   a,    106   b,    106   c,    106   d  into a combustion volume  108 . 
         [0020]    The combustion system  100  further includes a first voltage source  110   a  and a first ionizer  111   a.  The first voltage source  110   a  is operatively coupled to the controller  102 . The first voltage source  110   a  is responsive to control by the controller  102  and outputs a first series of high voltage pulses. The first ionizer  111   a  is configured to receive the first series of high voltage pulses and eject first charges onto one or more of the series of fuel pulses  106   b,    106   d  to charge the series of fuel pulses  106   a,    106   b,    106   c,    106   d.    
         [0021]    The controller  102  may be configured to cause the fuel control apparatus  104  and the first ionizer  111   a  to cooperate to output a series of fuel pulses  106   a,    106   b,    106   c ,  106   d.  The series of fuel pulses  106   a,    106   b,    106   c,    106   d  may carry sequentially opposite polarity charges. For example, the first ionizer  111   a  may eject positive charges when a fuel pulse  106   a  is proximate and eject negative charges when a fuel pulse  106   b  is proximate. This pattern may continue such that fuel pulse  106   c  is charged positively and fuel pulse  106   d  is charged negatively. 
         [0022]    The series of fuel pulses  106   a,    106   b,    106   c  carrying sequentially opposite polarity charges may be electrostatically attracted to one another and form a series of fuel streams  112   a,    112   b,    112   c  that flow together to form respective vortices  114   a,    114   b,    114   c . Additionally and/or alternatively, the series of fuel pulses  106   a,    106   b,    106   c  carrying sequentially opposite polarity charges may be electrostatically attracted to one another and may be selected to form a series of vortices  114   a,    114   b,    114   c  separated in space from one another. The series of fuel pulses  106   a,    106   b,    106   c  carrying sequentially opposite polarity charges may be selected to form Taylor layers  116   a,    116   a ′,  116   b,    116   b ′ between the series of vortices  114   a,    114   b,    114   c.    
         [0023]    The electrostatically-driven flow of the Taylor layers  116   a,    116   a ′,  116   b,    116   b ′ into the series of vortices  114   a,    114   b,    114   c  may be selected to cause air or flue gas engulfment  118   a,    118   b,    118   b ′,  118   c  into the respective vortices  114   a,    114   b,    114   c . Additionally and/or alternatively, the electrostatically-driven flow of the Taylor layers  116   a,    116   a ′,  116   b,    116   b ′ into the series of vortices  114   a,    114   b,    114   c  may be selected to cause air and/or flue gas engulfment  118   a,    118   b,    118   b ′,  118   c  into the respective vortices  114   a,    114   b,    114   c  at a selected mixing rate in the vortices  114   a,    114   b,    114   c  corresponding to a Damkohler Number equal to or greater than 1. 
         [0024]    In the illustrated embodiment, the combustion system  100  further includes a second voltage source  110   b  and a second ionizer  111   b.  However, in other embodiments, the second voltage source  110   b  may be omitted. The second voltage source  110   b  may be operatively coupled to the controller  102 . The second ionizer  111   b  may be operatively coupled to the second voltage source  110   b.  The first voltage source  110   a  may be configured to output a first unipolar voltage. The second voltage source  110   b  may be configured to output a second unipolar voltage opposite in sign from the first unipolar voltage. 
         [0025]    The controller  102  may be configured to cause the fuel control apparatus  104  and the first ionizer  111   a  to cooperate to output a series of fuel pulses  106   a,    106   c  carrying first polarity charges. Additionally and/or alternatively, the controller  102  may be configured to cause the fuel control apparatus  104  and the second ionizer  111   b  to cooperate to output a series of fuel pulses  106   b,    106   d.  The series of fuel pulses  106   b ,  106   d  may carry second polarity charges opposite in polarity from the first polarity charges. 
         [0026]    The series of fuel pulses  106   a,    106   b,    106   c  carrying sequentially opposite polarity charges may be electrostatically attracted to one another and may form a series of fuel streams  112   a,    112   b,    112   c.  The series of fuel streams  112   a,    112   b,    112   c  may flow together to form respective vortices  114   a,    114   b,    114   c.  Additionally and/or alternatively, the series of vortices  114   a,    114   b,    114   c  may be separated in space from one another. 
         [0027]    According to an embodiment, the series of fuel pulses  106   a,    106   b,    106   c  carrying sequentially opposite polarity charges may be selected to form Taylor layers  116   a,    116   a ′,  116   b,    116   b ′ between the series of vortices  114   a,    114   b,    114   c.  Additionally and/or alternatively, the electrostatically-driven flow of the Taylor layers  116   a,    116   a ′,  116   b ,  116   b ′ into the series of vortices  114   a,    114   b,    114   c  may be selected to cause air or flue gas engulfment  118   a,    118   b,    118   b ′,  118   c  into the respective vortices  114   a,    114   b,    114   c.  A mixing rate in the vortices  114   a,    114   b,    114   c  may be selected. The selected mixing rate may correspond to a Damkohler Number equal to or greater than 1. 
         [0028]    In an embodiment, the fuel control apparatus  104  and the first ionizer  111   a  may be configured as an electrostatic ionizing fuel injector  120 . For example, U.S. Pat. No. 8,245,951; which, to the extent not inconsistent with the disclosure herein, is incorporated by reference, and discloses suitable charge injectors that may be used with the combustion systems disclosed herein. 
         [0029]    In an embodiment, the fuel control apparatus  104 , the first ionizer  111   a,  and the second ionizer  111   b  may be configured as a bipolar electrostatic ionizing fuel injector  120 . The first ionizer  111   a  may be configured as a first ion-ejecting mesh. The second ionizer  111   b  may be configured as a second ion-ejecting mesh electrically insulated or isolated from the first ion-ejecting mesh. 
         [0030]    In an embodiment, the first ionizer  111   a  may include and/or be configured as a first carbon nanotube (CNT) coating, and the second ionizer  111   b  may include and/or be configured as a second CNT coating electrically insulated and/or isolated from the first CNT coating. 
         [0031]    In the illustrated embodiment, the combustion system  100  further includes a flame holder  122 . However, in other embodiments, the flame holder  122  may be omitted. The flame holder  122  may be configured to anchor a flame  124  formed as a series of vortices  114   a,    114   b,    114   c.  The series of vortices  114   a,    114   b,    114   c  may be formed from the series of charged fuel pulses  106   a,    106   b,    106   c,    106   d.  The flame holder  122  may include a grounded conductor and may include a bluff body. The flame  124  may include charged Taylor layers  116   a,    116   a ′,  116   b,    116   b ′ between the vortices  114   a,    114   b,    114   c.    
         [0032]    In some embodiment, the combustion system  100  may include a data communication interface  126  included and/or operatively coupled to the controller  102 . The controller  102  may be configured to receive data through the data communication interface  126  and may select the fuel control apparatus  104  and ionizer pulse frequency responsive to the received data. Additionally and/or alternatively, the controller  102  may be configured to receive data through the data communication interface  126  and may select a voltage source  110   a  output voltage responsive to the received data. 
         [0033]    In an embodiment, the fuel control apparatus  104  may include a fuel flow modulator. For example, the fuel flow modulator may include one or more of a piezoelectric valve, an electro-magnetic valve, a rotary valve, a slide valve, an actuated ball valve, or a micro-electro-mechanical system (MEMS) valve configured to modulate fuel flow from the fuel control apparatus  104 . 
         [0034]    In operation, the controller  102  may to receive data through the data communication interface  126  and may select a maximum modulated fuel flow rate of the fuel flow modulator responsive to the received data. The controller  102  may be configured to cause the fuel control apparatus  104  and the first ionizer  111   a  to output charged fuel pulses  106   a,    106   b,    106   c,    106   d  at one or more frequencies. For example, the one or more frequencies may be selected to avoid resonance in the combustion volume  108 . Additionally and/or alternatively, the one or more frequencies may be sub-harmonics of a resonance frequency of the combustion volume  108 . 
         [0035]    In other embodiments, the controller  102  may be configured to cause the fuel control apparatus  104  and the first ionizer  111   a  to output charged fuel pulses  106   a,    106   b ,  106   c,    106   d  at a spread spectrum of frequencies. The spread spectrum of frequencies may be selected to avoid resonance in the combustion volume  108 . 
         [0036]    In other embodiments, the controller  102  may be configured to cause the fuel control apparatus  104  and the ionizer  111   a  to output charged fuel pulses  106   a,    106   b ,  106   c,    106   d  at a range of frequencies. For example, the range of frequencies may include a low frequency corresponding to a low heat output rate from a flame  124 . As another example, the range of frequencies may include a high frequency corresponding to a high heat output rate from a flame  124 . The flame  124  may be supported by the charged fuel pulses  106   a,    106   b,    106   c,    106   d.    
         [0037]    As yet another example, the controller  102  may be configured to cause the fuel control apparatus  104  and the ionizer  111   a  to output charged fuel pulses  106   a,    106   b ,  106   c,    106   d  at a low fuel volume per pulse. The low fuel volume per pulse may correspond to a low heat output rate from a flame  124  supported by the charged fuel pulses  106   a,    106   b,    106   c,    106   d.  The ionizer  111   a  may be configured to apply a low total charge to the low fuel volume pulses  106   a,    106   b,    106   c,    106   d    
         [0038]    Additionally and/or alternatively, the controller  102  may be configured to cause the fuel control apparatus  104  and the first ionizer  111   a  to output charged fuel pulses  106   a,    106   b,    106   c,    106   d  at a high fuel volume per pulse. The high fuel volume per pulse may correspond to a high heat output rate from a flame  124  supported by the charged fuel pulses  106   a,    106   b,    106   c,    106   d.  The ionizer  111   a  may be configured to apply a high total charge to the high fuel volume pulses  106   a,    106   b,    106   c,    106   d . The controller  102  may be configured to drive the first voltage source  110   a  to output a voltage proportional to a fuel flow rate of the fuel flow apparatus  104 . Additionally and/or alternatively, the controller  102  may be configured to drive the fuel control apparatus  104  to output a fuel flow rate proportional to the first voltage source  110   a  output voltage. 
         [0039]    In certain embodiments, the fuel pulses  106   a,    106   b,    106   c,    106   d  may be formed as a fuel aerosol. 
         [0040]    In some embodiments, the combustion system  100  may include one or more field electrodes. The one or more field electrodes may be configured to apply one or more electric fields to drive movement of the charged fuel pulses  106   a,    106   b,    106   c,    106   d  and/or charged vortices produced by the charged fuel pulses. 
         [0041]    The first voltage source  110   a  and/or the first and second voltage sources  110   a ,  110   b  may be configured to cause the first ionizer  111   a  and/or first and second ionizers  111   a,    111   b  to output unequal amounts of positive and/or negative ions onto the series of fuel pulses  106   a,    106   b,    106   c,    106   d  such that combustion vortices  114   a,    114   b,    114   c  produced by the fuel pulses carry a bias charge or bias voltage. 
         [0042]    The formation of the vortices  114   a,    114   b,    114   c  may generally cause recombination of opposite charges carried by donor fuel pulses. When the number of positive charges carried by one fuel pulse is substantially equal to the number of negative charges carried by a sequentially neighboring fuel pulse, the net charge carried by the combustion reaction  124  may be neutral. In some embodiments, the combustion reaction  124  to carry a net charge. For example, one or more field electrodes may apply one or more electric fields to cause a selected movement, selected heat transfer, selected radiated blackbody emission, etc. of or from the combustion reaction  124 . A residual bias charge or bias voltage may be created in the combustion reaction  124  by applying a biased charge to the fuel pulses  106   a,    106   b,    106   c,    106   d.  The biased fuel charge may consist essentially of unequal numbers of positive and negative charges applied to successive fuel pulses. 
         [0043]    One or more embodiments are directed to a method for controlling a combustion reaction includes modulating a fuel control apparatus to output a series of fuel pulses, modulating an ionizer to apply charges to the series of fuel pulses, and supporting a combustion reaction with the series of charged fuel pulses.  FIG. 2  is a flow chart of a method for operating a combustion system according to a more specific embodiment. For example, the method  200  may be implemented by one or more of the embodiments of the combustion system  100  disclosed herein. 
         [0044]    According to an embodiment, in act  202 , a fuel control apparatus may select a modulation frequency. The modulation frequency may be selected to be proportional to an ionizer modulation frequency. In act  204 , an ionizer modulation frequency may be selected. The ionizer modulation frequency may be selected to be proportional to a fuel control apparatus modulation frequency. In act  206 , a fuel control apparatus modulated flow rate may be selected. The fuel control apparatus modulated flow rate may be selected to be proportional to an ionizer charge ejection rate. In act  208 , an ionizer modulated charge ejection rate may be selected. The ionizer modulated charge ejection rate may be selected to be proportional to a fuel control apparatus modulated flow rate, for example. According to an embodiment, an ionizer modulated charge phase may be included. The ionizer modulated charge phase may be selected relative to a fuel control apparatus modulation phase to synchronize charge output to a presence of a modulated fuel pulse. In act  210 , a fuel control apparatus may be modulated to output a series of fuel pulses. In act  212 , an ionizer may be modulated to apply charges to the series of fuel pulses. In act  214 , the charged fuel pulses may cause vortices to form. In act  216  a combustion reaction may be supported with the series of charged fuel pulses. 
         [0045]      FIG. 3  depicts an embodiment of a combustion system  300  including a pulsing mechanism  302 , a combustion chamber  304  and a feedback control system  306 . The combustion chamber  304  may include one or more electrodes  308  configured to apply charge, voltage, electric field, or combinations thereof to flame  310 . A variety of electrode  308  configurations may be employed depending on the application, and a plurality of waveforms and current intensities may be applied to the flame  310  via the electrodes  308 . 
         [0046]    The feedback control system  306  may include a programmable controller  312 , one or more probes  314 , and an amplifier  316 . A “probe” may refer to a sensor device, which may detect and measure one or more combustion parameters such as temperature, emissions, luminosity, among others. 
         [0047]    The amplifier  316  and the pulsing mechanism  302  may be connected to the programmable controller  312 , which manages the application of charge, voltage, electric field, or combinations thereof to the flame  310  through the electrode  308 , as well as controlling the pulsing frequency of the fuel supplied by the pulsing mechanism  302 . 
         [0048]    The pulsing mechanism  302  may be employed for injecting fuel and/or air in pulses into the combustion chamber  304  for producing the flame  310 . According to various embodiments, the pulsing mechanism  302  is employed to inject fuel. 
         [0049]    The feedback control system  306  may be responsible for analyzing parameters measured by the probes  314  which may be located in different regions of the combustion chamber  304 . The probes  314  may detect a variety of combustion and electric parameters in the flame  310 , such as NO x  and CO in exhaust gases. Such parameters may be communicated to the programmable controller  312  to determine behavior and characteristics of the flame  310  during combustion. Suitable probes  314  may include thermal, electric, optical sensors, among others. 
         [0050]    The programmable controller  312  may calculate different characteristics of the flame  310 , according to the probes  314  input. Subsequently, the programmable controller  312  may send a control signal to the amplifier  316  in order to energize the electrodes  308  for a corresponding application of voltage, charge, and or electric field that may adjust different characteristics of the flame  310  such as flame shape, position, luminosity and the like, according to the application. 
         [0051]    The flame  310  may exhibit a positive charge due to a majority amount of positively charged species in the flame  310 , generated during combustion. In an embodiment, a nozzle  318  may be charged to function as a charging electrode  308  to induce a majority of charge to the flame  310 . 
         [0052]    According to various embodiments, using the combustion systems disclosed herein for staging a combustion process and applying charge, voltage, electric field, or combinations thereof to a flame may increase one or more of heat transfer, improve mixing of reactants, lower combustion temperatures, or reduce harmful emissions such as NO x  and CO. For example,  FIG. 4  illustrates a fuel staging process  400  in the combustion system  300  in which fuel packets  402  may be injected into the combustion chamber  304 . The pulsing mechanism  302  (as shown in  FIG. 3 ) may include a pulsing frequency described as an ON/OFF sequence of pulses driven by the programmable controller  312 . The pulsing mechanism  302  may allow the injection of the fuel packets  402  into the combustion chamber  304 , while air packets  404  may enter through an air inlet port  406 . For example, the pulsing mechanism  302  or any pulsing mechanism disclosed herein may include rotative devices, Helmholtz resonators, or insulated injectors. When the fuel staging process  400  is ON, the fuel packets  402  may be injected into the combustion chamber  304 . On the other hand, during OFF mode, air packets  404  may be formed. The ON/OFF sequence of the pulsing mechanism  302  may be driven by a control waveform generated by the programmable controller  312 , which may also synchronize the application of charge, voltage, electric field, or combinations thereof to the flame  310  through the electrode  308 . In an embodiment, the programmable controller may generate a single waveform to control pulsing mechanisms and energization of the electrodes. In another embodiment, the programmable controller may generate two different waveforms with a phase relationship to control pulsing mechanism and energization of electrodes. 
         [0053]    The fuel staging process  400  may allow a higher accuracy of fuel injection since more precise volumes of fuel may be delivered when needed. Furthermore, combustion with smaller fuel volumes such like fuel packets  402 , may allow combustion with lower temperature, which may reduce NO x  production and improve heat transfer since less heat is wasted by convection. 
         [0054]    According to various embodiments, a plurality of pulsing mechanisms may be employed in order to stage combustion by pulsing fuel in liquid, solid, or gaseous state and/or air. For example, the pulsing mechanisms may include rotative devices, Helmholtz resonators, or insulated injectors. The pulsing mechanisms may pulse fuel packets while being synchronized with the application of charge, voltage, electric field, or combinations thereof to a flame through one or more electrodes. The synchronization of pulsed fuel packets and application of a voltage, charge, electric field, or combinations thereof to the flame may be performed by a programmable controller operating within a feedback control system. 
         [0055]      FIG. 5A  illustrates an embodiment of a waveform  500  that may be generated by the programmable controller  312  (as shown in  FIG. 3 ) to synchronize the fuel staging process  400  (as shown in  FIG. 4 ) with the application of charge, voltage, electric field, or combinations thereof to the flame  310  through the electrode  308 . The waveform  500  may be modulated between high voltage V H  and low voltage V L  in a pattern characterized by period P. The high voltage V H  and low voltage V L  may be selected as equal magnitude variations above and below a mean voltage V 0 , whereby mean voltage V 0  may be a ground voltage. The period P may include a duration t L  corresponding to low voltage V L  and another duration t H  corresponding high voltage V H , where t L  plus t H  may equal P. 
         [0056]    For example, when the waveform  500  is at V H , the pulsing mechanism  302  may operate at ON mode and feed a fuel packet  402  to the flame  310 , where the size of the fuel packet  402  may depend on duration t H , as well as the fuel flow rate. Simultaneously, when the waveform  500  is at V H , the electrode  308  may apply a positive charge to the flame  310 . Subsequently, at V L , the pulsing mechanism  302  may switch to OFF mode and stop the supply of the fuel packet  402  to the flame  310  within duration t L . Substantially simultaneously, when the waveform  502  is at V L , the electrode  308  may apply a negative charge to flame  310 . The process may continue with the synchronized application of the fuel packets  402  and electric charges to the flame  310 . 
         [0057]    Referring now to  FIG. 5B , two different waveforms  504  and waveform  506  may be generated by the programmable controller  312  to drive the electrode  308  and the pulsing mechanism  302 , respectively. The waveform  504  may drive the electrode  308  for the application of positive and negative charges to the flame  310 , while the waveform  506  may drive the pulsing mechanism  302  for the injection of the fuel packets  402  to the flame  310 . As shown in  FIG. 5B , the waveform  504  may exhibit a phase shift or a lag of about 50% with respect to the waveform  506 . 
         [0058]    Additionally, various effects may be produced over the fuel packets  402  and the air packets  404  according to the disclosed waveforms. Additionally, the disclosed waveforms may present a plurality of shapes, frequencies, periods, amplitudes, and phase shifts according to the application. 
         [0059]      FIG. 6  depicts an embodiment of the pulsing mechanism  302  in which a rotative gate system  600  is employed in order to inject the fuel packets  402  into the flame  310 . The rotative gate system  600  may inject the fuel packets  402  in stages of time and space, enabling an improved mixing rate and ignition. The rotative gate system  600  may inject a variety of liquid or gas fuels, depending on the application. 
         [0060]    The rotative gate system  600  may include a pressure chamber  602 , a pump  604 , a rotative gate  606 , a mechanical driver  608 , and a shaft  610 . The rotative gate system  600  may be connected to the programmable controller  312  through the mechanical driver  608 . 
         [0061]    Fuel  614  may be delivered to the pressure chamber  602  by the pump  604 . The pressure chamber  602  may enclose the rotative gate  606 , which may have an aperture  612 . Moreover, the rotative gate  606  may be connected to the mechanical driver  608  by the shaft  610 , whereby the mechanical driver  608  may be driven by the programmable controller  312 . Suitable mechanical drivers  608  may include electric engines, internal combustion engines, turbines, and the like. 
         [0062]    As the rotative gate  606  swivels, the aperture  612  may be either aligned or unaligned with respect to the nozzle  618 , allowing or stopping the supply of the fuel packet  402  to the flame  310 . Alignment of the aperture  612  may determine the ON/OFF sequence of the pulsing mechanism  302 , whereby alignment of aperture  612  may depend on the angular speed of mechanical driver  608  driven by the programmable controller  312  using the waveforms  502 ,  506 . 
         [0063]      FIG. 7  illustrates an embodiment of the pulsing mechanism  302  in which a generally cylindrical gate system  700  is employed to inject the fuel packets  402  into the flame  310 . The cylindrical gate system  700  may inject the fuel packets  402  in stages of time and space, enabling an improved mixing rate and ignition. The cylindrical gate system  700  may inject a variety of liquid or gas fuels, depending on the application. 
         [0064]    In an embodiment, the cylindrical gate system  700  may pulse the fuel packets  402  into the flame  310 . The cylindrical gate system  700  may include a pressure chamber  702 , the pump  604 , a cylindrical gate  704 , the mechanical driver  608 , and the shaft  610 . The cylindrical gate system  700  may be connected to the programmable controller  312  through the mechanical driver  608 . 
         [0065]    Fuel  614  may be delivered to the pressure chamber  702  by the pump  604 . The pressure chamber  702  may enclose the cylindrical gate  704 , which may have a passage  706 . Moreover, the cylindrical gate  704  may be connected to the mechanical driver  608  by the shaft  610 , whereby the mechanical driver  608  may be driven by the programmable controller  312 . Suitable mechanical drivers  608  may include electric engines, internal combustion engines, turbines, and the like. 
         [0066]    As the cylindrical gate  704  swivels, the passage  706  may be either aligned or unaligned with respect to the nozzle  318 , allowing or stopping the supply of the fuel packet  402  to the flame  310 . Alignment of the passage  706  may determine the ON/OFF sequence of the pulsing mechanism  302 , whereby alignment of the passage  706  may depend on the angular speed of the mechanical driver  608  driven by the programmable controller  312  using the waveforms  502 ,  506 . 
         [0067]      FIG. 8  illustrates an embodiment of the pulsing mechanism  302  in which a Helmholtz resonance system  800  may be used to inject fuel and/or air into the combustion chamber  304 . The Helmholtz resonance system  800  may inject a variety of liquid or gas fuels, depending on the application. In an embodiment, the Helmholtz resonance system  800  may inject the fuel packets  402  to the flame  310 . The Helmholtz resonance system  800  may include a Helmholtz resonator  802 , an inlet port  804 , the nozzle  318 , and the pump  604 . For example, as used herein, a “Helmholtz resonator” may refer to a container, which may induce a natural resonant frequency in fluids. A “natural resonant frequency” may refer to a frequency at which a fluid or a system naturally oscillates when it has been set into motion. 
         [0068]    The pump  604  may deliver the fuel  614  to the Helmholtz resonator  802 , which may connect the inlet port  804  to the nozzle  318 . The Helmholtz resonator  802  may resonate the fuel  614  to induce the formation of the fuel packets  402  at the nozzle  318 . The Helmholtz resonator  802  has the ability of increasing or decreasing natural resonant frequencies of incoming fuel  614 . Furthermore, frequency of pulsations may be directly related to shape, volume and size of the Helmholtz resonator  802 , the inlet port  804  and the nozzle  318 , as well as speed of the fuel  614  flowing through the Helmholtz resonator  802  and fuel  614  characteristics, such as viscosity and density. 
         [0069]    More than one Helmholtz resonator  802  may be employed in order to achieve different frequency ranges of the fuel packets  402  pulsations. When a plurality of Helmholtz resonators  802  with different or same sizes are employed, a plurality of permutations in frequencies may be achieved. Since Helmholtz resonators  802  do not have moving parts, reliability in the entire pulsed fuel system may be increased, also reducing maintenance costs. 
         [0070]    The Helmholtz resonance system  800  may be in synchronization with the application of a charge, voltage, electric field, or combinations thereof to the flame  310 . Period P of the waveforms  502 ,  504  for driving the electrode  308  may be synchronized with a permanent frequency configured in the Helmholtz resonance system  800 . 
         [0071]      FIG. 9  illustrates an embodiment of the pulsing mechanism  302  in which an insulated injector system  900  may inject the fuel packets  402  to the flame  310 . The insulated injector system  900  may inject a variety of liquid or gas fuels, according to the application. 
         [0072]    The insulated injector system  900  may include an insulated injector  902 , the pump  604 , and the nozzle  904 . In addition, the insulated injector system  900  may be connected to the programmable controller  312  in the feedback control system  306 . 
         [0073]    Fuel  614  may be delivered to the insulated injector  902  through the pump  604 . The insulated injector  902  may be isolated from electric fields generated by the electrode  308 . Electrical insulation may be required for protecting sensitive components of the insulated injector system  900 . The insulated injector system  900  may include solenoid injectors, piezoelectric injectors, mechanically driven injectors and the like. 
         [0074]    The nozzle  904  in the insulated injector system  900  may be opened or closed according to the ON/OFF sequence required for pulsing the fuel packets  402  into the flame  310 . The programmable controller  312  may drive the open/close operation of the nozzle  904  using the waveforms  502 ,  506  which may synchronize with the application voltage, charge, electric field, or combinations thereof applied to the flame  310  through the electrode  308  and according to the waveforms  502 , and  504 . 
         [0075]    While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.