Abstract
Due to high dilution and /or high supercharging of a spark ignition engine, the ignition environment is getting severe. Thereby, it is an important key technology to develop next-generation’s spark ignition system by clarifying discharge channel behavior during flow and initial flame kernel growth process. In this paper, the authors investigated the discharge and the ignitability of the mixture in diluted flow field using a constant volume combustion chamber. As a result, the ignitability was found to depend on discharge current, discharge energy and /or ambient gas velocity. Also, the extension of discharge channel by ambient gas flow was found to shorten the discharge duration and also to increase the discharge energy, leading to good ignitability.
