Thermo-acoustic Studies of Combustion Chamber with Acoustic Damper

Abstract

In gas turbine combustors, there is always a pressure fluctuation. In such combustion chamber a growing acoustic wave is also observed. A coupling between acoustic wave and unsteady heat release causes combustion instability. When the combustion instability occurs, large amplitude of sound with high level of vibration is observed in combustion chamber which also causes structural damage to the engine. Now a day most of the chambers developed are having combustion instability problem. To overcome such instabilities and improve the combustion system operability, Helmholtz resonator system is considered as a passive absorber. The present work focuses on the combustion instability by solving coupled dynamics equations and generalising the relations between the input and output parameters using neural network model. The pressure and velocity distribution are illustrated in this paper, phase diagram of acoustic velocity and pressure are found out. Solid model of combustion chamber is used to do modal analysis.