Method and apparatus for electrical control of heat transfer

Abstract

A heat exchange system includes an electrode configured to electrostatically control a flow of a heated gas stream in the vicinity of a heat transfer surface and/or a heat-sensitive surface.

1 . A method for stimulating heat transfer, comprising:
 providing a heated gas carrying electrically charged species;   temporally modulating a first electrode to create an electric field to drive the heated gas to flow adjacent to a heat transfer surface; and   transferring heat from the gas to the heat transfer surface.   
     
     
         2 . The method for stimulating heat transfer of  claim 1 , wherein temporally modulating the first electrode to drive the heated gas includes driving the first electrode to one or more voltages selected to attract oppositely charged species, and the attracted oppositely charged species imparting momentum transfer to the heated gas. 
     
     
         3 . The method for stimulating heat transfer of  claim 1 , wherein providing a heated gas carrying charged species includes burning at least one fuel, the combustion reaction providing at least a portion of the charged species. 
     
     
         4 . The method for stimulating heat transfer of  claim 3 , wherein the combustion reaction provides substantially all the charged species. 
     
     
         5 . The method for stimulating heat transfer of  claim 1 , further comprising temporally modulating at least one second electrode to preferentially purge electrons from the heated gas. 
     
     
         6 . The method for stimulating heat transfer of  claim 5 , wherein the at least one second electrode includes a burner assembly. 
     
     
         7 . The method for stimulating heat transfer of  claim 5 , wherein providing a heated gas carrying ionized species includes supporting a flame with a burner assembly; and
 wherein the at least one second electrode includes an electrode positioned at a location nearer the burner assembly than the distance between the burner assembly and the heat transfer surface.   
     
     
         8 . The method for stimulating heat transfer of  claim 5 , wherein the at least one second electrode is positioned to sweep electrons out of the flow of the heated gas. 
     
     
         9 . The method for stimulating heat transfer of  claim 5 , wherein the temporal modulation of the at least one second electrode includes providing an alternating voltage configured to drive the electrons to combine with a positively charged conductor including the at least one second electrode. 
     
     
         10 . The method for stimulating heat transfer of  claim 5 , wherein the at least one second electrode is modulated between a range of positive voltages at a frequency of about 200 Hz or more. 
     
     
         11 . The method for stimulating heat transfer of  claim 10 , wherein the at least one second electrode is modulated at a frequency of about 300 Hz or more. 
     
     
         12 . The method for stimulating heat transfer of  claim 10 , wherein the range of positive voltages includes about 0 volts to +500 volts or more. 
     
     
         13 . The method for stimulating heat transfer of  claim 12 , wherein the range of positive voltages includes about 0 volts to +10 KV or more. 
     
     
         14 . (canceled) 
     
     
         15 . The method for stimulating heat transfer of  claim 14 , wherein temporally modulating the first electrode includes modulating the first electrode at a frequency of about 500 Hz or less. 
     
     
         16 . The method for stimulating heat transfer of  claim 1 , wherein the heated gas carrying electrically charged species includes combustion gasses. 
     
     
         17 . The method for stimulating heat transfer of  claim 1 , wherein the heat transfer surface includes the first electrode. 
     
     
         18 . The method for stimulating heat transfer of  claim 17 , wherein the heat transfer surface includes:
 a thermally conductive wall;   an electrical insulator disposed over at least a portion of the thermally conductive wall; and   the first electrode including an electrically conductive layer disposed over the electrical insulator.   
     
     
         19 .- 33 . (canceled) 
     
     
         34 . A method for protecting a temperature-sensitive surface, comprising:
 providing a heated gas carrying electrically charged species; and   temporally modulating a first electrode to form an electric; field to drive the heated gas to flow distal from a temperature-sensitive surface to reduce the transfer of heat from the gas to the temperature-sensitive surface.   
     
     
         35 . The method for protecting a temperature-sensitive surface of  claim 34 , wherein temporally modulating the first electrode to drive the heated gas includes driving the first electrode to one or more voltages selected to attract oppositely charged species, and the attracted oppositely charged species imparting momentum transfer to the heated gas. 
     
     
         36 . The method for protecting a temperature-sensitive surface of  claim 34 , wherein providing a heated gas carrying charged species includes burning at least one fuel, the combustion reaction providing at least a portion of the charged species. 
     
     
         37 . The method for protecting a temperature-sensitive surface of  claim 36 , wherein the combustion reaction provides substantially all the charged species. 
     
     
         38 . The method for protecting a temperature-sensitive surface of  claim 34 , further comprising temporally modulating at least one second electrode to preferentially purge electrons from the heated gas. 
     
     
         39 . The method for protecting a temperature-sensitive surface of  claim 38 , wherein the at least one second electrode includes a burner assembly. 
     
     
         40 . The method for protecting a temperature-sensitive surface of  claim 38 , wherein providing a heated gas carrying ionized species includes supporting a flame with a burner assembly; and
 wherein the at least one second electrode includes an electrode positioned at a location nearer the burner assembly than the distance between the burner assembly and the temperature-sensitive surface.   
     
     
         41 . The method for protecting a temperature-sensitive surface of  claim 38 , wherein the at least one second electrode is positioned to sweep electrons out of the flow of the heated gas. 
     
     
         42 . The method for protecting a temperature-sensitive surface of  claim 38 , wherein the temporal modulation of the at least one second electrode includes providing an alternating voltage configured to drive the electrons to combine with a positively charged conductor including the at least one second electrode. 
     
     
         43 . The method for protecting a temperature-sensitive surface of  claim 38 , wherein the at least one second electrode is temporally modulated between a range of positive voltages at a frequency of about 200 Hz or more. 
     
     
         44 . The method for protecting a temperature-sensitive surface of  claim 43 , wherein the at least one second electrode is modulated at a frequency of about 300 Hz or more. 
     
     
         45 . The method for protecting a temperature-sensitive surface of  claim 43 , wherein the range of positive voltages includes about 0 volts to +500 volts or more. 
     
     
         46 . The method for protecting a temperature-sensitive surface of  claim 45 , wherein the range of positive voltages includes about 0 volts to +10 KV or more. 
     
     
         47 . The method for protecting a temperature-sensitive surface of  claim 38 , wherein temporally modulating the first electrode includes modulating the first electrode between a range of negative voltages. 
     
     
         48 . The method for protecting a temperature-sensitive surface of  claim 47 , wherein temporally modulating the first electrode includes modulating the first electrode at a frequency of about 500 Hz or less. 
     
     
         49 . The method for protecting a temperature-sensitive surface of  claim 34 , wherein the heated gas carrying electrically charged species includes combustion gases. 
     
     
         50 . The method for protecting a temperature-sensitive surface of  claim 34 , wherein the heat-sensitive surface includes the first electrode. 
     
     
         51 . The method for protecting a temperature-sensitive surface of  claim 50 , wherein the temperature-sensitive surface includes:
 a wall;   an electrical insulator disposed over at least a portion of the wall; and   the first electrode including an electrically conductive layer disposed over the electrical insulator.   
     
     
         52 .- 73 . (canceled)