Exhaust Emission Level Reduction in Two-Stroke Engine using In-Cylinder Combustion Control

The present work studied exhaust emission levels from small low-output two-stroke spark ignition engines and investigated the means to reduce exhaust emission levels. The work presented here investigated two different approaches for in-cylinder combustion control to reduce emission levels. The first approach employed piston crown treatment with copper-coating to identify any improvement in combustion performance; the second approach employed Keronite® coating, i.e, ceramic-coating to act as a thermal barrier to improve combustion or reduce thermal losses. The engine performance and emission levels obtained for similar loading conditions using these approaches were compared with that of baseline engine performance. The study found that significant reduction of emission levels especially un-burned hydrocarbon and carbon monoxide could be obtained by applying in-cylinder coating in two-stroke engines.