Effects of nanosecond repetitively pulsed plasma discharges on a propagating hydrogen–air flame

Abstract

Pressure-gain combustion cycles have been a topic of intense scientific research in recent years. Pulse detonation combustors are one promising technology for successfully implement-ing these pressure-gain cycles. These combustors frequently rely on obstacles for accelerating a propagating flame and inducing the deflagration-to-detonation transition. The use of obsta-cles, however, has several disadvantages. Replacing such obstacles with nanosecond repetitively pulsed plasma discharges may be advantageous to developing this technology further. Proof of concept has been achieved demonstrating the effectiveness of this strategy at enhancing the transition to detonation. This work is a closer investigation into the effect of these plasma discharges on flames with varying turbulence intensities and propagation velocities. For velocities below 200 m/s, the effect is minimal and transition to detonation does not occur. The effect of plasma discharges on flame acceleration also begins to diminish for the current configuration and pulse repetition frequency at speeds above 400 m/s. This give a range where nanosecond repetitively pulsed plasma discharges may be used effectively for efficient flame acceleration and transition to detonation.