Effects of Gasoline-Air Enrichment with HRG Gas on Efficiency and Emissions of a SI Engine

The addition of hydrogen to the gasoline-air mixture may contribute significantly towards accelerating the combustion process, with the beneficial effects on engine performance and emissions.

The present contribution describes the results of an experimental research where gasoline-air mixture was enriched with a Hydrogen Rich Gas (HRG) produced by the electrical dissociation of water. The HRG analysis shows the presence of hydrogen and oxygen together with some additional species.

Experiments were carried out at engine light and partial load. Detailed results of the measurements are shown, namely engine torque and efficiency, exhaust emissions, cyclic variability, heat release rates and combustion duration. The possibilities of improving engine performance and emissions in correlation with the amount of HRG, the equivalence ratio and the engine operating condition are thus outlined.