Stochastic dynamical system identification applied to combustor stability margin assessment

System identification;Stability margin;Combustion instability

Cordeiro, Helio de Miranda ; Aerospace Engineering

University:Georgia Institute of Technology

Department:Aerospace Engineering

关键词: System identification;    Stability margin;    Combustion instability;   

Others  :  https://smartech.gatech.edu/bitstream/1853/28167/1/cordeiro_helio_m_200905_phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

A new approach was developed to determine the operational stability margin of a laboratory scale combustor. Applying modern and robust techniques and tools from Dynamical System Theory, the approach was based on three basic steps. In the first step, a gray-box thermoacoustical model for the combustor was derived. The second step consisted in applying System Identification techniques to experimental data in order to validate the model and estimate its parameters. The application of these techniques to experimental data under different operating conditions allowed us to determine the functional dependence of the model parameters upon changes in an experimental control parameter. Finally, the third step consisted in using that functional dependence to predict the response of the system at different operating conditions and, ultimately, estimate its operational stability margin. The results indicated that a low-order stochastic non-linear model, including two excited modes, has been identified and the combustor operational stability margin could be estimated by applying a continuation method.