Control of Combustion Dynamics Using Fuel System Impedance

Abstract

Combustion oscillations (dynamics) have become a major challenge in the development of low-emission premix combustors. In this paper, a variable impedance fuel system is used to modulate the phase and magnitude of the combustion response in a laboratory scale 30 kW combustor. With the proper choice of design parameters, this technique demonstrates significant attenuation of dynamics pressures, over a wide range of operating conditions. The technique is similar to active control, but does not require high frequency actuators. The paper will report on the key design variables that should be considered when using this concept to improve dynamic stability.