Mitigating the response of premixed swirl flames to acoustic excitation by nanosecond repetitively pulsed discharges at elevated pressures

Abstract

This paper shows that nanosecond repetitively pulsed discharges were able to mitigate the response of lean methane-air swirl flames to acoustic excitations, at pressures up to 3 bar. Flame transfer functions with and without plasma discharges were investigated at pressures of 1.2, 2.0, and 3.0 bar, in a frequency range 48–380 Hz. Results show that the plasma discharges decreased by up to 50% the gain of the flame transfer functions, regardless of the pressure. Mechanisms responsible for this effect are discussed.