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Show USE OF AN ELECTRIC FIELD TO ENHANCE STABILITY IN A CYCLONIC COMBUSTOR C.H. Berman, RJ. Gill, and H.F. Calcote AeroChem Research Laboratories, Inc. P.O. Box 12 Princeton, New Jersey 08542 and T. Y. Xiong and B. Kramnik Institute of Gas Technology 4201 West 36th Street Chicago, Illinois 60632-3898 ABSTRACT The flame stability has been increased and the emissions reduced in a pilot-scale cyclonic combustor by the application of a high voltage electric field. The electrical energy consumption was about 0.002 % of the design firing rate. Enhanced flame stability was indicated by a dramatic reduction in carbon monoxide and unburned hydrocarbons at high values of excess air. Because of the complex structure of the recirculating gas flow, the combustion characteristics were mapped for electrical, thermal , and flow properties to design and determine the best location of the dc electrodes. NOx reduction was not achieved (it was already very low) probably due to improved combustion near the walls with accompanying increase in temperature. Improved electrode designs should lead to improved flame stability and reduction in NOx ' I. FUNDAMENTAL RESEARCH AeroChem has previously demonstrated 1,2 that high voltage electric fields can increase the lean stability limit of laminar and turbulent premixed flames supported-on cylindrical burners. This also results in reduced NOx emissions, with the mechanism thought to be that of simply allowing the flame to burn at lower equivalence ratios and thus at lower temperatures , thus reducing thermal NOx. |