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Show Presented at 2012 AFRC Annual Meeting, September 5-‐7, Salt Lake City, UT © 2012 ClearSign Combustion Corp. all rights reserved 2 Since new reactants are continually flowing into the flame volume and new products are continually flowing out of it, power must be continually added to the reaction zone. The high voltage provides an electric field that influences the flame and its surroundings in beneficial ways, described presently. Although the signal is high voltage, it is low amperage and power. Experiments up to 400,000 Btuh have shown that the required power is less than 0.1% of the total thermal power released by the flame. This is much lower than required for plasmas, as the goal is not to create a massive dissociation of electrons from the bulk fluid, but merely to enhance and direct the resulting ions that are naturally formed by the combustion process. Charge is introduced in a convenient way, for example via a conductive solid such as the burner nozzle or external electrode (direct charging), using a fluid carrier, e.g., FLAME ON FLAME (FOF™) charging; or from a distance using remote charging methods. Figure 2 shows a several such examples from patents pending. Direct charging is perhaps the most straightforward; however, FOF allows conversion of conventional burners to ECC enabled versions with replacement of the pilot; remote charging allows the flame to acquire charge from inside the air plenum, burner tile, or any other convenient place some distance from the flame in the case that one desires more benign environments for the electrode. Remote charging uses thin electrodes that represent virtually no obstruction to air flow. (a) (b) (c) Direct Charging FOF Remote Charging Figure 2. Some Methods of Charging the Flame. (a) shows a conductive electrode directly contacting the flame. (b) shows the FLAME-‐ON-‐FLAME (FOF™) method, wherein a pilot flame carries charge to a main flame. (c) illustrates a remote charging method, whereby ions are emitted from a remote source to the flame without physical contact. These demonstrated effects and additional methods are the subject of various patents pending. Technically, only the ionic species respond to the imposed electric field; however, collision with neutral species is inevitable and results in a bulk flow. The direction and nature of the bulk flow can be tailored for particular applications. Waveforms and algorithms may be automated in real time to achieve particular effects and are the subject of additional patents pending. Some existing and potential applications include 1. increased fuel-‐air mixing with attendant reduction of excess air, CO, soot, and PM, |