Modeling and model predictive control of combustion instabilities in a multi-section combustion chamber using two-port elements

Abstract

This paper deals with the modeling and control of thermo-acoustic instabilities in a combustion chamber, using a Helmholtz resonator approach and two-port elements. The perturbation of the pressure alongside the combustion chamber is modeled by one dimensional pressure waves, incorporating the turbulent effect of sudden cross sectional area changes in the duct. A non-linear flame model is used to describe the interactions between pressure and heat release oscillations. Finally, an offset-free MPC is designed to stabilize the thermo- acoustic instability in the experimental setup. I. INTRODUCTION Reduction of emission of pollutants is of major concern in modern gas turbines. Strict regulations have been im- plemented about emission of NOx (1), (2). The formation of NOx increases exponentially with the temperature level occurring in the combustion process. However, for high efficiency, it is desirable to operate the turbine at the highest allowable inlet temperature. To solve this trade-off between