A Three-Dimensional Study of Flame Propagation in a Spark Ignition Engine

The combustion process in a spark ignition engine has been investigated in terms of flame development and subsequent propagation throughout the combustion chamber. Multiple ionization gaps coupled with advanced electronic instrumentation were used to detect progression of the flame in three dimensions. New information concerning knocking combustion has shown that there is no need to postulate any discontinuity in the rate of the combustion process to explain the occurrence of knock.