Technical Paper
High-Frequency Ignition Characteristics in a 4-Valve SI Engine with Tumble-Swirl Flows
1998-05-04
981433
A high-frequency ignition system was developed to improve the stability of initial flame development under the lean burn condition. The electrical principle of the high-frequency ignition system is based on successive spark discharges in a spark plug. The ignition system provides electronically controlled charges in spark duration (1∼2msec) and restriking rates (10∼30kHz). Flow characteristics of tumble-swirl were varied with swirl control valve attached at the inlet ports. Four different flow patterns were tested by the combination of tumble and swirl strengths achieved by various shapes of swirl control valve. The effects of flow and ignition characteristics on the combustion performances and their interaction were investigated in a 4-valve SI engine. Flow characteristics were quantified by steady flow tests and in-cylinder flow measurements.
