Suppression of Combustion Oscillation of Premixed Flames by Active Control

Combustion-induced oscillations in a duct were observed by changing the duct length and the mixture equivalence ratio. The wall pressure fluctuations in the combustion duct and the OH emission intensity of the flame were well-correlated with the free field sound pressure. A closed-loop active control using the above signals and a Open-loop active control were studied to suppress combustion oscillations. Based on the results of the experiments, the possibility of suppression of combustion oscillation by a forced oscillation in the upstream feed tube of the facility was suggested.