The role of water in transient plasma ignition for combustion

Summary form only given. Pulse detonation engines offer the potential for a single, air- breathing, propulsion system that can operate from subsonic speeds (including take-off) to high Mach number flight. Critical to this technology is rapid repetition rate operation. Plasma-based ignition systems based on short pulse, high voltage pulsed power have been shown to decrease the ignition time in experimental system. The presence of water in the fuel-air mixture, however, has been shown to adversely affect the performance of these ignition systems. Herein, we report on simulations of the plasma chemistry from the application of the pulsed power (10´s of ns) through the ignition time (100´s of microsecond). These simulations suggest a long-lived neutral species created by the transient plasma ignition process that are strongly affected by water, and can play a role in both combustion processes. Comparison with experimental results, potential mitigation schemes for the water effects, and implications for internal combustion engines will be discussed.