Multi-point ignition of hydrogen/air mixtures with single pulsed nanosecond surface dielectric barrier discharge. Morphology of the discharge at elevated pressures.

The initiation of combustion of lean H2/Air mixtures with nanosecond surface dielectric barrier discharge (nSDBD) was studied experimentally at high initial pressures up to 6 bar. The ignition is initiated with two different discharge modes: streamer and filamentary. The influence of the discharge structure and energy deposition on the ignition is demonstrated. Three regimes of multi-point ignition were observed: ignition with a few kernels, quasi-uniform ignition along the edge of high voltage electrodes and ignition along the plasma channels. The minimum ignition energy of the discharge and ignition delay time of combustion have been measured. The velocities of flame propagation are analyzed.