<div class="htmlview paragraph">A two-chamber bomb was used to investigate the effect of fluid motions on combustion characteristics, in particular exhaust emissions. Variations in prechamber volume, connecting orifice geometry, air-fuel charge stratification, and initial turbulence of the charge were examined. Tests were run over a wide air-fuel ratio range.</div> <div class="htmlview paragraph">High speed motion pictures were used to study flame propagation and fluid motions. The results show that when the strength of the turbulent jet from the prechamber is varied over a significant range, there is little or no effect on the emissions of oxides of nitrogen (NO_x) over the entire air-fuel ratio range. Hydrocarbon (HC) emissions were found to increase with jet strength in the portion of the lean air-fuel range of most interest (i.e., around 17:1). However, for very lean mixtures the trend was reversed.</div>