Modelling the Nonlinear Dynamics of Combustion Instabilities in Gas Turbines Towards Active Control

Abstract

A main obstacle to the use of premixed flames in gas turbine combustors is the occurrence of combustion instabilities. In this paper, we propose a model for the description of the coupling between the acoustic field and the heat release process. While the gasdynamics is modelled by means of transcendental transfer functions, the flame description, worked out on physical basis, is a nonlinear lumped parameter system. The developed model is intended for active control, and it accounts for the limit-cycle phenomenon.