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Title: Active control of combustion instability

Abstract

The principle of 'antisound' is used to construct a method for the suppression of combustion instabilities. This active instability control (AIC) method uses external acoustic excitation by a loudspeaker to suppress the oscillations of a flame. The excitation signal is provided by a microphone located upstream of the flame. This signal is filtered, processed, amplified, and sent to the loudspeaker. The AIC method is validated on a laboratory combustor. It allows the suppression of all unstable modes of the burner for any operating ratio. The influence of the microphone and loudspeaker locations on the performance of the AIC system is described. For a given configuration, domains of stability, i.e., domains where the AIC system parameters provide suppression of the oscillation, are investigated. Measurements of the electric input of the loudspeaker show that the energy consumption of the AIC system is almost negligible and suggest that this method could be used for industrial combustor stabilization. Finally, a simple model describing the effects of the AIC system is developed and its results compared to the experiment.

Authors:
; ;
Publication Date:
Research Org.:
Institute B fur Thermodynamik, Technische Universitat, Munich
OSTI Identifier:
5551041
Resource Type:
Journal Article
Resource Relation:
Journal Name: Combust. Flame; (United States); Journal Volume: 70:3
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; COMBUSTORS; COMBUSTION INSTABILITY; DAMPING; ACOUSTIC TESTING; BURNERS; COMBUSTION CONTROL; COMBUSTION KINETICS; ENERGY EFFICIENCY; FLAME PROPAGATION; MATHEMATICAL MODELS; OPERATION; SOUND WAVES; CHEMICAL REACTION KINETICS; CONTROL; EFFICIENCY; INSTABILITY; KINETICS; MATERIALS TESTING; NONDESTRUCTIVE TESTING; REACTION KINETICS; TESTING; 421000* - Engineering- Combustion Systems

Citation Formats

Lang, W., Poinsot, T., and Candel, S. Active control of combustion instability. United States: N. p., 1987. Web. doi:10.1016/0010-2180(87)90109-X.
Lang, W., Poinsot, T., & Candel, S. Active control of combustion instability. United States. doi:10.1016/0010-2180(87)90109-X.
Lang, W., Poinsot, T., and Candel, S. Tue . "Active control of combustion instability". United States. doi:10.1016/0010-2180(87)90109-X.
@article{osti_5551041,
title = {Active control of combustion instability},
author = {Lang, W. and Poinsot, T. and Candel, S.},
abstractNote = {The principle of 'antisound' is used to construct a method for the suppression of combustion instabilities. This active instability control (AIC) method uses external acoustic excitation by a loudspeaker to suppress the oscillations of a flame. The excitation signal is provided by a microphone located upstream of the flame. This signal is filtered, processed, amplified, and sent to the loudspeaker. The AIC method is validated on a laboratory combustor. It allows the suppression of all unstable modes of the burner for any operating ratio. The influence of the microphone and loudspeaker locations on the performance of the AIC system is described. For a given configuration, domains of stability, i.e., domains where the AIC system parameters provide suppression of the oscillation, are investigated. Measurements of the electric input of the loudspeaker show that the energy consumption of the AIC system is almost negligible and suggest that this method could be used for industrial combustor stabilization. Finally, a simple model describing the effects of the AIC system is developed and its results compared to the experiment.},
doi = {10.1016/0010-2180(87)90109-X},
journal = {Combust. Flame; (United States)},
number = ,
volume = 70:3,
place = {United States},
year = {Tue Dec 01 00:00:00 EST 1987},
month = {Tue Dec 01 00:00:00 EST 1987}
}
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