A dynamic model of moving flames for the analysis and control of combustion instabilities

Gas-turbine combustion systems based on premixed flames, for certain operating conditions, exhibits unacceptable high pressure oscillations due to combustion instabilities. In this paper, a nonlinear mathematical model for the description of these phenomena is presented. The model is built via a thorough description of both the gasdynamics and the combustion process, which is concisely outlined. The core of the paper is devoted to the use of the model for the study of the flame limit-cycle behaviour and on the corresponding flame front oscillations within the combustor chamber. The developed model is intended for active control of combustion instabilities usage, and is therefore a description of the leading dynamics.