Active Control of Combustion Instability in a Liquid-Fueled Low-NOx Combustor

Abstract

A practical active control system for the mitigation of combustion instability has been designed and demonstrated in a lean, premixed, single-nozzle combustor at realistic engine operating conditions. A full-scale engine fuel nozzle was modified to incorporate a simple fuel flow actuator. Results indicate that the system was capable of reducing pressure fluctuations by 82 percent (15 dB or 5.6×) while maintaining or reducing NOx and CO emissions levels.