Combustion system with a corona electrode

Abstract

A corona electrode may be used to apply an electric field to a combustion reaction to cause a response in the combustion reaction. The corona electrode may include an ion-ejecting feature having a small radius.

1 . An electrode system for a combustion apparatus, comprising:
 at least one corona electrode configured for mounting proximate to a combustion reaction; and   a power supply operatively coupled to the at least one corona electrode;   wherein the power supply and the at least one corona electrode are configured to apply an electric field to a region adjacent to the combustion reaction.   
     
     
         2 . The electrode system for a combustion apparatus of  claim 1 , wherein the electric field strength has a maximum magnitude adjacent to the corona electrode at least double an average electric field strength in the region adjacent to the combustion reaction. 
     
     
         3 .- 4 . (canceled) 
     
     
         5 . The electrode system for a combustion apparatus of  claim 1 , wherein the power supply is configured to apply a substantially constant electrical potential to the at least one corona electrode. 
     
     
         6 .- 13 . (canceled) 
     
     
         14 . The electrode system for a combustion apparatus of  claim 1 , wherein the power supply and the at least one corona electrode are configured to cause an average electric field strength sufficient to meet a corona inception voltage according to Peek's law. 
     
     
         15 .- 16 . (canceled) 
     
     
         17 . The electrode system for a combustion apparatus of  claim 22 , further comprising:
 a burner configured to support the combustion reaction;   wherein the burner further comprises the dull electrode and is configured for electrical continuity with a conductive surface of the combustion reaction and to define a counter voltage to cooperate with the at least one corona electrode to produce the electric field.   
     
     
         18 .- 21 . (canceled) 
     
     
         22 . The electrode system for a combustion apparatus of  claim 1 , further comprising:
 at least one dull electrode configured to cooperate with the at least one corona electrode to produce the electric field.   
     
     
         23 .- 24 . (canceled) 
     
     
         25 . The electrode system for a combustion apparatus of  claim 22 , wherein the dull electrode includes a toroid or torus. 
     
     
         26 . (canceled) 
     
     
         27 . The electrode system for a combustion apparatus of  claim 22 , wherein the dull electrode is operatively coupled to the power supply to be driven to an instantaneous electrical potential different from the instantaneous electrical potential of the corona electrode. 
     
     
         28 . The electrode system for a combustion apparatus of claim  22 , wherein the dull electrode is configured to be held substantially at ground potential. 
     
     
         29 . The electrode system for a combustion apparatus of  claim 22 , wherein the dull electrode is configured to be galvanically isolated from ground and from other electrical potentials. 
     
     
         30 . The electrode system for a combustion apparatus of  claim 1 , wherein the corona electrode includes a taper to a tip having a radius of 0.1 inch or less. 
     
     
         31 . (canceled) 
     
     
         32 . A method for applying an electric field or voltage to a combustion reaction, comprising:
 supporting at least one corona electrode proximate to or contacting a combustion reaction, the at least one corona electrode including a tip or edge of small radius;   causing ion ejection in an electrical field concentration volume peripheral to the tip or edge by applying an electrical potential to the at least one corona electrode; and   responsive to the application of the electrical potential and ion ejection, causing a response in the combustion reaction.   
     
     
         33 . The method for applying an electric field to a combustion reaction of  claim 32 , wherein supporting at least one corona electrode proximate to the combustion reaction includes supporting the at least one corona electrode proximate to but not contacting the combustion reaction. 
     
     
         34 .- 35 . (canceled) 
     
     
         36 . The method for applying an electric field or voltage to a combustion reaction of  claim 32 , further comprising supporting at least one dull electrode proximate to or contacting the combustion reaction to cooperate with the at least one corona electrode to produce an electric field. 
     
     
         37 .- 38 . (canceled) 
     
     
         39 . The method for applying an electric field or an electrical potential to a combustion reaction of  claim 32 , wherein supporting the dull electrode proximate to or contacting the combustion reaction includes supporting a toroid or torus. 
     
     
         40 . The method for applying an electric field or an electrical potential to a combustion reaction of claim  34 , further comprising:
 driving the dull electrode to an instantaneous voltage substantially the same as the instantaneous voltage applied to the corona electrode.   
     
     
         41 . The method for applying an electric field or voltage to a combustion reaction of claim  34 , further comprising:
 holding the dull electrode substantially at ground potential.   
     
     
         42 . The method for applying an electric field or voltage to a combustion reaction of claim  34 , further comprising:
 isolating the dull electrode from ground and from electrical potentials other than a potential received from the corona electrode.   
     
     
         43 . The method for applying an electric field or voltage to a combustion reaction of  claim 32 , wherein supporting at least one corona electrode proximate to but not contacting the combustion reaction includes supporting a corona electrode including a taper to a tip having a radius of 0.1 inch or less. 
     
     
         44 .- 45 . (canceled) 
     
     
         46 . The method for applying an electric field or voltage to a combustion reaction of  claim 32 , wherein applying the electrical potential to the at least one corona electrode includes applying an electric field to a region adjacent to the combustion reaction, the electric field strength having a maximum magnitude in the voltage concentration volume peripheral to the small radius tip or edge at least double an average electric field strength in the region adjacent to the combustion reaction. 
     
     
         47 . (canceled) 
     
     
         48 . The method for applying an electric field or voltage to a combustion reaction of  claim 32 , wherein applying the electrical potential to the at least one corona electrode includes applying a periodic voltage to the at least one corona electrode. 
     
     
         49 .- 53 . (canceled) 
     
     
         54 . The method for applying an electric field or an electrical potential to a combustion reaction of  claim 32 , wherein applying the voltage to the at least one corona electrode includes applying an average electric field strength in the region adjacent to the combustion reaction between 0.3 kV/m to 1000 kV/m. 
     
     
         55 . (canceled) 
     
     
         56 . The method for applying an electric field or an electrical potential to a combustion reaction of  claim 32 , wherein applying the electrical potential to the at least one corona electrode includes applying an average electric field strength sufficient to meet a corona inception voltage according to Peek's law. 
     
     
         57 .- 60 . (canceled) 
     
     
         61 . The method for applying an electric field or an electrical potential to a combustion reaction of  claim 32 , further comprising providing a burner in electrical continuity with the combustion reaction, wherein a conductive stoichiometric surface of the combustion reaction forms a substantially equipotential surface in electrical continuity with the burner; and further comprising applying a voltage condition to the burner. 
     
     
         62 . The method for applying an electric field or an electrical potential to a combustion reaction of  claim 61 , wherein applying an electrical potential condition to the burner includes operating a power supply that also applies the electrical potential to the at least one corona electrode. 
     
     
         63 . The method for applying an electric field or an electrical potential to a combustion reaction of  claim 61 , wherein applying an electrical potential condition to the burner includes holding the burner substantially at ground potential. 
     
     
         64 . The method for applying an electric field or an electrical potential to a combustion reaction of  claim 61 , wherein applying an electrical potential condition to the burner includes galvanically isolating the burner from ground and from voltage sources such that the burner is electrically floating. 
     
     
         65 . A burner system, comprising:
 a burner configured to support a flame in a flame position; and   a first electrode having a sharp tip, the first electrode being positioned, relative to the burner, such that the sharp tip of the first electrode is oriented toward the flame position, at a distance that is sufficient to prevent contact of the sharp tip with a flame supported by the burner.   
     
     
         66 . The system of  claim 65  wherein the sharp tip is one of a plurality of sharp tips of the first electrode, each of the plurality of sharp tips being positioned along a first axis. 
     
     
         67 . The system of  claim 66  wherein the sharp tips of the plurality of sharp tips are arranged in a saw tooth pattern. 
     
     
         68 . The system of  claim 66  wherein the first electrode is positioned with the first axis lying parallel to a central axis of the flame position. 
     
     
         69 . The system of  claim 65  wherein the first electrode has a blade shape including a longitudinal taper to the sharp tip, which forms an edge of the blade shape. 
     
     
         70 . (canceled) 
     
     
         71 . The system of  claim 65  wherein the first electrode is supported by a structure configured to vary the position of the first electrode, relative to the flame position. 
     
     
         72 .- 74 . (canceled) 
     
     
         75 . The system of  claim 65 , comprising a voltage source electrically coupled to the electrode and configured to apply to the first electrode a voltage having a magnitude sufficient to cause the first electrode to produce a corona discharge from the sharp tip. 
     
     
         76 . The system of  claim 75 , comprising a second electrode electrically coupled to the voltage source and positioned, relative to the first electrode and burner, such that a portion of the charged particles ejected by the first electrode toward the second electrode impinge on the flame position. 
     
     
         77 .- 79 . (canceled) 
     
     
         80 . The system of  claim 75 , comprising a second electrode coupled to the voltage source, the second electrode being positioned and configured to apply a counter charge to a fluid stream ejected by the burner. 
     
     
         81 . (canceled) 
     
     
         82 . The system of  claim 80  wherein the second electrode has a toroidal shape and is positioned, relative to the burner, such that the fluid stream passes substantially along a central axis of the toroidal shaped second electrode. 
     
     
         83 . The system of  claim 82  wherein the second electrode is positioned to act as a flame anchor to a flame supported by the burner. 
     
     
         84 . The system of  claim 80  wherein the second electrode is outside the flame position. 
     
     
         85 . The system of  claim 65 , comprising an electrode shield positioned between at least a portion of the first electrode, including the sharp tip, and the flame position, and configured to block transmission of radiant heat. 
     
     
         86 . The system of  claim 65  wherein the sharp tip is one of a plurality of sharp tips of the first electrode, the system further comprising an electrode shield shaped and positioned between each of the plurality of sharp tips of the first electrode and the flame position, and configured to block transmission of radiant heat. 
     
     
         87 .- 98 . (canceled) 
     
     
         99 . The method for applying an electric field or voltage to a combustion reaction of claim  34 , comprising ablating the sharp tip of the discharge electrode, including ablating a core and an outer layer of the discharge electrode at respective rates that maintains a portion of the core extending as the sharp tip from the outer layer. 
     
     
         100 . The method for applying an electric field or voltage to a combustion reaction of  claim 99 , comprising maintaining a selected distance between the sharp tip and the flame by extending the discharge electrode at a rate that is substantially equal to a rate of ablation of the discharge electrode. 
     
     
         101 . A device, comprising:
 a first electrode having a sharp tip at a first end of the first electrode; and   an electrode shield electrically and mechanically coupled to the electrode in a position on a longitudinal axis of the sharp tip and spaced a distance from the sharp tip.   
     
     
         102 .- 103 . (canceled)