Effects of trapped residual concentration and surface temperature on the combustion process of a two-stroke cycle spark ignition engine with an air-assisted fuel injection system

Experiments were conducted on a cycle engine with a low-pressure air-assisted fuel injection system at idling condition. The main areas of investigation were the effects of trapped residual concentration, air injection pressure and surface temperature on combustion and HC emission. Results showed that skip firing, which reduced trapped residuals, had a significant improvement in the concentration of oxygen as well as the residuals trapped in the cylinder. A suitable combination of skip firing and surface temperature control could be a potential measure to improve the combustion and the HC emission at light load.