Burner with electrodynamic flame position control system

Abstract

A burner includes a flame position actuator configured to control a location at which a flame is held. Combustion supported at a first location corresponds to high fuel dilution. An electric charge is applied to the fuel stream. If electrical power is lost or removed, the flame is shifted to a location corresponding to a lower fuel dilution.

1 . A burner with electrodynamic flame position control system, comprising:
 a charging mechanism configured to apply a charge or voltage to a flame or a fuel stream supporting the flame;   a first flame support surface disposed adjacent to the fuel stream configured to support the flame when the charge or voltage is applied to the flame or the fuel stream;   an aerodynamic flame holder disposed away from the fuel stream; and   a flame position actuator configured to selectively engage the aerodynamic flame holder with the fuel stream to cause the aerodynamic flame holder to support the flame when the charge or voltage is not applied to the flame or fuel stream.   
     
     
         2 . The burner with electrodynamic flame position control system of  claim 1 , further comprising a fuel nozzle. 
     
     
         3 . The burner with electrodynamic flame position control system of  claim 1 , wherein the charging mechanism is disposed to apply a charge or voltage to the fuel stream between the aerodynamic flame holder and the first flame support surface. 
     
     
         4 . The burner with electrodynamic flame position control system of  claim 1 , wherein the charging mechanism is disposed to apply a charge or voltage to the flame above the first flame support surface. 
     
     
         5 . The burner with electrodynamic flame position control system of  claim 1 , wherein the charging mechanism is configured to impart a positive charge or voltage on the flame or fuel stream. 
     
     
         6 . The burner with electrodynamic flame position control system of  claim 1 , wherein the first flame support surface is disposed more distal from the fuel nozzle than the aerodynamic flame holder. 
     
     
         7 . The burner with electrodynamic flame position control system of  claim 1 , wherein the first flame support surface is configured to support the flame at a distance from a fuel nozzle corresponding to a reduced fuel concentration compared to the fuel concentration proximate the aerodynamic flame holder. 
     
     
         8 .- 9 . (canceled) 
     
     
         10 . The burner with electrodynamic flame position control system of  claim 7 , wherein the first flame support surface includes a perforated flame holder configured to support a low NOx flame in a plurality of gas passages formed to extend through the perforated flame holder. 
     
     
         11 . (canceled) 
     
     
         12 . The burner with electrodynamic flame position control system of  claim 1 , wherein the first flame support surface includes a flame support electrode configured to attract the charge or voltage applied to the flame or fuel stream. 
     
     
         13 . The burner with electrodynamic flame position control system of  claim 12 , wherein the attraction of the charge or voltage applied to flame or fuel stream to the flame support electrode causes the flame to be supported by the flame support electrode. 
     
     
         14 . The burner with electrodynamic flame position control system of  claim 12 , wherein the flame support electrode is held at voltage ground. 
     
     
         15 . The burner with electrodynamic flame position control system of  claim 12 , further comprising a voltage source operatively coupled to the flame support electrode;
 wherein the voltage source is configured to drive the flame support electrode to a voltage opposite in sign from the charge or voltage applied to the flame or fuel stream.   
     
     
         16 . (canceled) 
     
     
         17 . The burner with electrodynamic flame position control system of  claim 1 , further comprising a voltage source; and
 one or more field electrodes operatively coupled to the voltage source and disposed to apply an electric field or second charges to the flame, the electric field or second charges being selected to enhance combustion of the flame.   
     
     
         18 .- 24 . (canceled) 
     
     
         25 . The burner with electrodynamic flame position control system of  claim 1 , further comprising a voltage source operatively coupled to the charging mechanism. 
     
     
         26 .- 29 . (canceled) 
     
     
         30 . The burner with electrodynamic flame position control system of  claim 1 , wherein the charging mechanism includes an ion-ejecting electrode. 
     
     
         31 .- 33 . (canceled) 
     
     
         34 . The burner with electrodynamic flame position control system of  claim 1 , wherein the charging mechanism includes an ionizer. 
     
     
         35 .- 37 . (canceled) 
     
     
         38 . The burner with electrodynamic flame position control system of  claim 1 , wherein the charging mechanism includes a fuel nozzle configured to eject ions into the fuel stream. 
     
     
         39 . The burner with electrodynamic flame position control system of  claim 1 , wherein the aerodynamic flame holder is configured to support the flame at a more stable fuel dilution than a flame supported by the first flame support surface. 
     
     
         40 . The burner with electrodynamic flame position control system of  claim 1 , wherein the flame position actuator is configured to cause the flame to be positioned at the first flame support surface when the charge or voltage is applied to the flame or fuel stream. 
     
     
         41 . The burner with electrodynamic flame position control system of  claim 1 , wherein the flame position actuator is configured to cause the flame to be positioned at the aerodynamic flame holder when the charge or voltage is not applied to the flame or fuel stream. 
     
     
         42 . The burner with electrodynamic flame position control system of  claim 1 , wherein the flame position actuator is configured to automatically select the flame position responsive to presence or absence of electrical power or absence of charge or voltage applied to the flame or fuel stream. 
     
     
         43 . (canceled) 
     
     
         44 . The burner with electrodynamic flame position control system of  claim 1 , wherein the flame position actuator includes an aerodynamic flame holder retractor. 
     
     
         45 . The burner with electrodynamic flame position control system of  claim 44 , wherein the flame position actuator is configured to hold the aerodynamic flame holder away from the fuel stream when the charge or voltage is applied to the flame or fuel stream;
 wherein the flame position actuator is configured to hold the aerodynamic flame holder away from the fuel stream against a restoring force that remains coupled to the aerodynamic flame holder when the charge or voltage is not tipped to the flame or fuel stream.   
     
     
         46 .- 52 . (canceled) 
     
     
         53 . The burner with electrodynamic flame position control system of  claim 1 , wherein the flame position actuator includes a fuel stream deflector configured to cause the fuel stream to deflect away from the aerodynamic flame holder when the voltage is applied to the flame or fuel stream. 
     
     
         54 . The burner with electrodynamic flame position control system of  claim 53 , wherein the flame position actuator includes an ionic wind fuel stream deflector. 
     
     
         55 .- 62 . (canceled) 
     
     
         63 . A method for supporting a flame, comprising:
 applying a charge or voltage to a fuel stream or a flame supported by the fuel stream;   causing the fuel stream to flow along a path separated from an aerodynamic flame holder at a second location;   supporting the flame with the fuel stream at a first location;   stopping application of the charge or voltage to the fuel stream or the flame;   operating a flame position actuator to cause the fuel stream to flow along a path adjacent to the aerodynamic flame holder;   shifting the flame from the first location to a second location; and   supporting the flame at the second location.   
     
     
         64 . The method for supporting a flame of  claim 63 , wherein causing the fuel stream to flow along a path separated from an aerodynamic flame holder includes operating a flame position actuator that is configured to hold the aerodynamic flame holder away from the fuel stream when the charge or voltage is applied to the flame or fuel stream. 
     
     
         65 . The method for supporting a flame of  claim 63 , wherein shifting the flame from the first location to the second location includes forming a vortex adjacent to the aerodynamic flame holder to cause the flame to maintain ignition adjacent to the aerodynamic flame holder when no charge or voltage is applied to the fuel stream or flame. 
     
     
         66 . (canceled) 
     
     
         67 . The method for supporting a flame of  claim 63 , further comprising:
 applying an electric field or charge to the flame while the flame is at the first location, the electric field being selected to enhance combustion.   
     
     
         68 . The method for supporting a flame of  claim 63 , further comprising:
 supporting a perforated flame holder at the first location to support a low NOx flame in a plurality of gas passages formed to extend through the perforated flame holder, and to supply heat to the fuel stream to maintain combustion.   
     
     
         69 . (canceled) 
     
     
         70 . The method for supporting a flame of  claim 63 , wherein operating the flame position actuator to cause the fuel stream to flow along a path adjacent to the aerodynamic flame holder includes actuating a movement of at least a portion of the aerodynamic flame holder. 
     
     
         71 .- 89 . (canceled) 
     
     
         90 . The method for supporting a flame of  claim 63 , wherein operating the flame position actuator to cause the fuel stream to flow along a path adjacent to the aerodynamic flame holder includes stopping deflection of the fuel stream. 
     
     
         91 .- 93 . (canceled) 
     
     
         94 . The method for supporting a flame of  claim 63 , further comprising:
 resuming the application of the charge or voltage to the fuel stream or the flame;   operating the flame position actuator to cause the fuel stream to flow along the path separated from the aerodynamic flame holder at the second position; and   shifting the flame from the second location to the first location.   
     
     
         95 .- 104 . (canceled) 
     
     
         105 . The method for supporting a flame of  claim 63 , wherein supporting the flame at a first location includes supporting the flame with a first flame support surface at the first location disposed more distal from a fuel nozzle than the second location. 
     
     
         106 . The method for supporting a flame of  claim 63 , further comprising applying a voltage condition to a flame support electrode at the first location; and
 wherein supporting the flame at the first location includes attracting the charge or voltage applied to the fuel stream or flame with the voltage condition applied to the flame support electrode.   
     
     
         107 .- 113 . (canceled) 
     
     
         114 . The method for supporting a flame of  claim 63 , wherein supporting the flame at a first location includes supporting a lean, low oxides of nitrogen (NOx) flame a distance from a fuel nozzle corresponding to a reduced fuel concentration compared to a fuel concentration proximate to the second location. 
     
     
         115 . (canceled) 
     
     
         116 . The method for supporting a flame of  claim 63 , further comprising, while the flame is supported at the first location, applying an electric field or second charges to the flame with one or more field electrodes, the electric field or second charges being selected to enhance combustion in the flame. 
     
     
         117 .- 123 . (canceled)