Cooled electrode and burner system including a cooled electrode

Abstract

According to embodiments, an electrode configured to provide an electric field to a flame or combustion gas produced by a flame may receive heat from the flame or the combustion gas. The electrode may be cooled to remove the heat received from the flame or combustion gas.

1 . An electrode system for a burner, comprising:
 a thermally coupled electrode configured to apply an electric field or eject electrically-charged ions to a region corresponding to a flame or combustion gas produced by the flame and to receive heat from the flame or the combustion gas; and   a cooling apparatus operatively coupled to the thermally coupled electrode and configured to remove the heat received by the thermally coupled electrode from the flame or the combustion gas.   
     
     
         2 . The electrode system for a burner  claim 1 , wherein at least a majority of heat removed by the cooling apparatus from the thermally coupled electrode corresponds to heat received from the flame or combustion gas produced by the tie flame. 
     
     
         3 . The burner system of  claim 1 , wherein heat removed by the cooling apparatus from the thermally coupled electrode includes heat caused by dissipation from electrical modulation of the thermally coupled electrode and heat received from the flame. 
     
     
         4 . The electrode system for a burner  claim 1 ,
 wherein the burner is configured to support the flame.   
     
     
         5 . The electrode system for a burner  claim 4 , wherein the burner further comprises:
 a fuel source configured to provide fuel for the flame;   electrical isolation configured to electrically isolate the fuel source from ground or voltages other than voltages corresponding to the thermally coupled electrode; and   an oxidizer source configured to provide oxidizer for the flame.   
     
     
         6 . The electrode system for a burner  claim 1 , further comprising:
 an electrode controller configured to apply a voltage corresponding to the electric field to the thermally coupled electrode through one or more electrical leads.   
     
     
         7 . The electrode system for a burner  claim 6 , wherein the cooling apparatus is operatively coupled to and controlled by the electrode controller. 
     
     
         8 . (canceled) 
     
     
         9 . The electrode system for a burner  claim 1 , further comprising:
 a heat sink operatively coupled to the cooling apparatus and configured to receive the heat received by the thermally coupled electrode from the flame or the combustion gas and removed from the thermally coupled electrode by the cooling apparatus.   
     
     
         10 . The electrode system for a burner  claim 1 , wherein the cooling apparatus is configured to output heat from the thermally coupled electrode to a heat sink including a heat exchange surface configured to pre-heat an oxidizer or gas fed to the flame. 
     
     
         11 . The electrode system for a burner  claim 1 , wherein the cooling apparatus is configured to output heat from the thermally coupled electrode to a heat sink including a heat exchange surface configured to pre-heat fuel fed to the flame. 
     
     
         12 . (canceled) 
     
     
         13 . The electrode system for a burner of  claim 1 , wherein the cooling apparatus is configured to output heat from the thermally coupled electrode to a liquid, gas, or solid heat sink that is not thermally coupled to the flame or the combustion gas. 
     
     
         14 . The electrode system for a burner of  claim 1 , further comprising:
 an electrical isolation system configured to reduce or substantially prevent current leakage from the thermally coupled electrode to a heat sink configured to receive heat removed from the thermally coupled electrode by the cooling apparatus.   
     
     
         15 . The electrode system for a burner of  claim 1 , wherein the cooling apparatus comprises:
 a thermo-electric cooler operatively coupled to remove the heat from the thermally coupled electrode.   
     
     
         16 . The electrode system for a burner of  claim 1 , wherein the thermally coupled electrode is configured to be fluid cooled. 
     
     
         17 . The electrode system for a burner of  claim 1 , wherein the cooling apparatus includes a heat pipe configured to receive heat from the flame or combustion gas via evaporation at an evaporator end and output the heat from the flame or combustion gas via condensation at a condenser end. 
     
     
         18 . The electrode system for a burner of  claim 17 , wherein a wall of the heat pipe forms an electrically conductive path of the electrode. 
     
     
         19 . (canceled) 
     
     
         20 . The electrode system for a burner of  claim 17 , wherein the electrode and the heat pipe further comprise:
 an electrically insulating coating configured to reduce or prevent communication of the voltage place on the electrode to ground, to another voltage, or to an electrically conductive cooling fluid arranged to receive heat from the condenser end of the heat pipe.   
     
     
         21 . The electrode system for a burner of  claim 17 , wherein an exterior surface of the wall of the heat pipe includes one or more smooth contours configured to reduce or prevent charge concentration and arcing to or through the flame. 
     
     
         22 . The electrode system for a burner of  claim 1 , wherein the thermally coupled electrode further comprises:
 a wall forming an electrical conductor and defining a fluid flow channel; and   at least one aperture formed in the wall;   wherein the fluid flow channel is configured to convey a cooling fluid from cooling fluid inlet to the aperture to transfer heat received from the wall to the cooling fluid and to output the heated cooling fluid to the flame or to combustion gas produced by the flame.   
     
     
         23 . (canceled) 
     
     
         24 . The electrode system for a burner of  claim 22 , further comprising:
 an electrically insulating coupling to the fluid flow channel configured to reduce or prevent communication of the voltage placed on the electrode to ground, to another voltage, or to an electrically conductive secondary cooling fluid.   
     
     
         25 . The electrode system for a burner of  claim 22 , wherein the wall includes one or more smooth contours configured to reduce or prevent charge concentration and arcing to or through the flame. 
     
     
         26 . The electrode system for a burner of  claim 22 , wherein the wall further comprises:
 an electrically insulating coating formed over at least a portion thereof to reduce or eliminate current flow to the cooling fluid.   
     
     
         27 . The electrode system for a burner of  claim 22 , wherein the cooling fluid includes a gas. 
     
     
         28 . The electrode system for a burner of  claim 27 , wherein the cooling fluid includes air. 
     
     
         29 . The electrode system for a burner of  claim 28 , wherein the aperture forms an overfire air port. 
     
     
         30 . The electrode system for a burner of  claim 22 , wherein the cooling fluid includes a liquid. 
     
     
         31 . The electrode system for a burner of  claim 1 , wherein the thermally coupled electrode further comprises:
 a wall defining an electrical conductor;   a first fluid flow channel formed within the wall and configured to convey received cooling fluid; and   a second fluid flow channel formed within the wall and configured to convey output cooling fluid.   
     
     
         32 . The electrode system for a burner of  claim 31 , wherein the first and second fluid flow channels are configured to respectively convey the cooling fluid at least a portion of a flow distance from a cooling fluid inlet port to a cooling fluid outlet port; and
 wherein at least one of the first and second fluid flow channels is configured to transfer heat from the wall to the cooling fluid.   
     
     
         33 . The electrode system for a burner of  claim 31 , further comprising:
 at least one fitting configured to couple the first and second fluid flow channels respectively to the cooling fluid inlet port and the cooling fluid outlet port;   wherein the fitting forms the cooling fluid inlet port and the cooling fluid outlet port.   
     
     
         34 . The electrode system for a burner of  claim 33 , wherein the at least one fitting is substantially electrically insulating. 
     
     
         35 . The electrode system for a burner of  claim 31 , wherein the first and second fluid flow channels are coaxial; and
 further comprising:   a tube or integrally formed wall defining the inner flow channel.   
     
     
         36 . The electrode system for a burner of  claim 31  wherein the first and second fluid flow channels include parallel lumens that are not coaxial. 
     
     
         37 . (canceled) 
     
     
         38 . The electrode system for a burner of  claim 31 , wherein the cooling fluid is electrically non-conductive. 
     
     
         39 .- 40 . (canceled) 
     
     
         41 . The electrode system for a burner of  claim 31 , wherein the cooling fluid is electrically conductive or potentially electrically conductive. 
     
     
         42 .- 44 . (canceled) 
     
     
         45 . The electrode system for a burner of  claim 41 , wherein the wall further comprises:
 an electrically insulating coating formed over at least a portion of surfaces of the wall or walls defining the first and second fluid flow channels;   wherein the electrically insulating coating is configured to reduce or eliminate current flow to the cooling fluid.   
     
     
         46 . The electrode system for a burner of  claim 45 , wherein the electrically insulating coating includes a ceramic coating. 
     
     
         47 . The electrode system for a burner of  claim 46 , wherein the electrically insulating coating includes a glass coating. 
     
     
         48 . The electrode system for a burner of  claim 1 , further comprising:
 an electrically isolated cooling fluid source configured to provide a cooling fluid to the thermally coupled electrode.   
     
     
         49 . The electrode system for a burner of  claim 48 , wherein the electrically Isolated cooling fluid source comprises:
 an electrically insulating tank or pool configured to hold a reservoir of cooling fluid.   
     
     
         50 . The electrode system for a burner of  claim 49 , further comprising:
 an electrically isolated or electrically insulating cooling fluid supply system configured to convey the cooling fluid from the reservoir of cooling fluid to a cooling fluid inlet operatively coupled to the thermally coupled electrode.   
     
     
         51 . The electrode system for a burner of  claim 50 , wherein the electrically isolated or electrically insulating cooling fluid supply system includes an electrically isolated or electrically isolating pump configured to pump the cooling fluid. 
     
     
         52 .- 53 . (canceled) 
     
     
         54 . The electrode system for a burner of  claim 49 , wherein the electrically isolated cooling fluid source further comprises:
 a cooling fluid supply configured to provide cooling fluid to the electrically insulating tank or pool through an antisiphon arrangement configured to prevent electrical conduction to the fluid supply.   
     
     
         55 . The electrode system for a burner of  claim 54 , wherein the electrically isolated cooling fluid source further comprises:
 a valve configured to cause the cooling fluid to be supplied across the antisiphon arrangement in a non-continuous stream that prevents electrical conduction from the cooling fluid reservoir to the cooling fluid supply.   
     
     
         56 . The electrode system for a burner of  claim 49 , wherein the electrically isolated cooling fluid source further comprises:
 a secondary coolant tank configured to hold a secondary coolant;   wherein the secondary coolant is arranged to receive heat from the cooling fluid reservoir through the electrically insulating tank or pool.   
     
     
         57 . A method for cooling an electrode subject to heating by a flame or a combustion gas produced by the flame, comprising:
 applying an electric field or ejecting electrically-charged ions to a flame or combustion gas with an electrode;   causing a detectable response in the flame or the combustion gas responsive to the electric field;   receiving heat from the flame or the combustion gas with the electrode; and   cooling the electrode to remove the heat received from the flame or the combustion gas.   
     
     
         58 . The method for cooling an electrode subject to heating by a flame or a combustion gas produced by the flame of  claim 57 , further comprising:
 generating heat in the electrode by Joule heating;   wherein the majority of heat removed by cooling corresponds to heat received from the flame.   
     
     
         59 . The method of  claim 58 , wherein substantially all the heat removed by cooling corresponds to heat received from the flame. 
     
     
         60 . The method of  claim 57 , further comprising:
 providing a source of fuel and oxidizer;   supplying fuel and an oxidizer to a burner; and   supporting the flame with the burner.   
     
     
         61 . The method of  claim 60 , further comprising:
 electrically isolating the fuel source from ground or voltages other than voltages corresponding to the electrode.   
     
     
         62 . The method of  claim 57 , further comprising:
 generating a waveform with a waveform generator;   amplifying the waveform to a time-varying voltage; and   applying the time-varying voltage to the electrode;   wherein the time-varying voltage applied to the electrode corresponds to the electric field applied to the flame or the combustion gas; and   wherein the waveform and an amount of amplification applied to the waveform are selected to cause the detectable response in the flame or the combustion gas.   
     
     
         63 . The method for of  claim 62 , wherein the waveform and the time-varying voltage are selected not to cause to eliminate or minimize Joule heating of the electrode. 
     
     
         64 . The method of  claim 62 , wherein the waveform and the time-varying voltage are selected to avoid causing arcing between the flame or other structures and the electrode; and
 wherein the waveform and the time-varying voltage cause no inductive or resistive heating of the flame or the combustion gas.   
     
     
         65 . The method of  claim 62 , further comprising:
 controlling a cooling apparatus operatively coupled to the electrode with a controller that generates the waveform.   
     
     
         66 . The method of  claim 57 , wherein the step of cooling the electrode includes operating a thermo-electric cooler. 
     
     
         67 . The method of  claim 57 , further comprising:
 providing at least one of an electrically isolating cooling fluid or an electrically isolated heat sink to receive heat from the electrode;   wherein the step of cooling the electrode to remove the heat received from the flame or the combustion gas includes transferring the heat received by the electrode to the electrically isolating cooling fluid or electrically isolated heat sink.   
     
     
         68 . The method of  claim 67 , wherein the step of providing the electrically isolating cooling fluid or the electrically isolated heat sink further includes providing an electrically non-conducting gas. 
     
     
         69 . The method of  claim 68 , wherein the step of providing the electrically non-conducting gas includes providing primary air or an oxidizer for the flame or the combustion gas; and
 wherein the step of transferring the heat received from the electrode to the electrically isolating cooling fluid or electrically isolated heat sink further comprises:   preheating the primary air or the oxidizer with the heat removed from the electrode; and   mixing the primary air or the oxidizer with a fuel or with the flame or the combustion gas.   
     
     
         70 . The method of  claim 68 , wherein the step of providing the electrically non-conducting gas includes providing overfire air or oxidizer for the flame; and
 wherein the step of transferring the heat received from the electrode to the electrically isolating cooling fluid or electrically isolated heat sink further comprises:   preheating the overfire air or oxidizer with the heat removed from the electrode; and   injecting the preheated overfire air or oxidizer into the flame or the combustion gas.   
     
     
         71 . The method of  claim 70 , wherein the step of preheating the overfire air or oxidizer with heat removed from the electrode includes passing the overfire air or oxidizer through one or more lumens comprising one or more walls formed in the electrode and convectively receiving the heat into the overfire air or oxidizer from the one or more walls of the one or more lumens; and
 wherein the step of injecting the preheated air or oxidizer into the flame or the combustion gas includes passing the convectively heated air or oxidizer from the one or more lumens through one or more apertures formed in the electrode and into the flame or combustion gas.   
     
     
         72 . The method of  claim 68 , wherein the step of providing the electrically non-conductive gas includes providing atmospheric air. 
     
     
         73 . The method of  claim 68 , wherein the step of transferring the heat to the electrically isolating cooling fluid further comprises:
 transferring heat from the heat sink to the electrically non-conductive gas through cooling fins.   
     
     
         74 . The method of  claim 67 , wherein the step of providing an electrically isolating cooling fluid or heat sink includes the step of providing an electrically non-conductive liquid coolant. 
     
     
         75 . The method of  claim 74 , wherein the step of providing a nonconductive liquid coolant includes providing a liquid fuel; and
 wherein the step of transferring the heat to the electrically isolating cooling fluid includes the step of transferring the heat to the liquid fuel to preheat the liquid fuel; and   further comprising:   conveying the preheated liquid fuel to a burner; and   fueling the flame with the preheated liquid fuel.   
     
     
         76 . The method of  claim 67 , wherein the step of providing an electrically isolating cooling fluid or heat sink further comprises:
 providing an electrically conductive liquid coolant; and   electrically isolating the electrically conductive liquid coolant from ground and from voltages other than a voltage applied to the electrode.   
     
     
         77 . The method of  claim 76 , wherein the step of providing the electrically conductive liquid coolant includes the step of providing an electrically conductive liquid fuel, water, a liquid metal, a molten salt or equivalents thereof. 
     
     
         78 . The method of  claim 76 , further comprising:
 transferring heat from the electrically isolate and electrically conductive liquid coolant to a secondary coolant or heat sink through an electrically non-conductive wall, heat exchanger, or tank.   
     
     
         79 . The method of  claim 76 , wherein the step of providing the electrically isolated and electrically conductive coolant further comprises:
 pumping the electrically isolated and electrically conductive liquid coolant from an electrically isolating coolant reservoir and past a heat sink operatively coupled to the electrode or through at least one fluid channel in the electrode; and   wherein electrically isolating the electrically conductive liquid coolant further comprises:   providing a pump that is electrically isolated or electrically isolating the pump from a pump drive motor.   
     
     
         80 . The method of  claim 76 , wherein the step of electrically isolating the electrically conductive liquid coolant from ground and from voltages other than a voltage applied to the electrode further comprises:
 providing the electrically conductive liquid coolant to a reservoir from a cooling fluid supply through an antisiphon arrangement that prevents electrical conduction between the fluid supply and the reservoir.   
     
     
         81 . The method of  claim 80 , wherein the step of providing the electrically isolated and electrically conductive liquid coolant to the reservoir from the cooling fluid supply through an antisiphon arrangement that prevents electrical conduction includes modulating a liquid coolant flow to prevent a continuous stream of the electrically conductive liquid coolant from bridging the antisiphon arrangement. 
     
     
         82 . The method of  claim 57 , further comprising:
 providing an electrical insulator between the electrode and one or more cooling fluid flow channels.   
     
     
         83 . The method for of  claim 57 , wherein the step of cooling the electrode to remove heat received from the flame or the combustion gas includes the step of passing a cooling fluid through the electrode. 
     
     
         84 . The method of  claim 57 , wherein the step of cooling the electrode to remove heat received from the flame includes the step of operating a heat pipe to remove the heat from the electrode. 
     
     
         85 . The method of  claim 84 , further comprising:
 transferring heat from the heat pipe to a cooling fluid.   
     
     
         86 . The method of  claim 85 , wherein the step of transferring heat from the heat pipe to the cooling fluid further comprises:
 passing primary combustion oxidizer, overfire oxidizer, or fuel across a condenser portion of the heat pipe to preheat the primary combustion oxidizer, overfire oxidizer, or fuel.   
     
     
         87 . The method of  claim 85 , further comprising:
 providing electrical insulation over at least a condenser portion of the heat pipe to prevent conduction of an electrode voltage to a cooling fluid passing across the condenser.