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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 7 In addition, the Figure 8 system shows a reduced exit temperature with ECC technology engaged indicating increased heat transfer to the surface (Figure 9). Figure 9. Thermocouple traces with and without ECC Engaged. Thermocouple traces for the Figure 8 apparatus are shown above. The cyan (Exit) trace shows a drop in stack exit temperature from 260 °F to 235 °F, indicating increased heat transfer to the cylindrical surface. Additionally, the magenta (Mid-‐Stack) trace shows a similar or greater decrease as well as diminished variation, while the navy (Inlet) trace shows a temperature increase in the inlet region of the device; taken together, the traces show that the combustion volume is more intimately mixed. It is known that a reduction in peak temperatures is often accompanied by NOx reduction. When the system is switched off (trailing gray zone) the traces resume their prior behavior (compare the thermocouple traces in the leading and trailing gray zones). 6. Flame shaping. Flame shape can also be dramatically affected (Figure 10). Until now, combustion engineers have had only buoyancy and momentum forces in their tool kit for shaping wayward flames. ECC technology provides a third force to shape flames. Figure 10 shows some interesting flame shapes generated from the technique. (a) System Off (b) System Engaged (c) System Engaged (d) System Engaged Figure 10. Flame Shaping with ECC Technology. The figure shows individual frames (top view) of a video from an operating bench-‐scale apparatus firing propane. In (a) the system is off, whereas in (b), (c), and (d) the system is engaged with a surrounding cylinder grounded. Owing |