Gaseous fuel for lower emissions during the cold start and warming up of spark ignition engines

Gasoline engines during cold starting (cranking) and warming-up duration, particularly, at low environmental temperatures have negative impact on air pollutions, especially for sub-zero degrees. To achieve a stable engine operation at low environment temperatures, extra fuel has to be injected inside the combustion chamber and as a consequence more emissions particularly hydrocarbons are emitted. In this study, fuel consumption, emissions and engine-start conditions have been examined using different gaseous fuels during the period from the ignition time until the catalyst reaching its lighting off temperature at no load conditions. The results showed that gaseous fuels reduces fuel consumption and emissions due to achieving substantial reduction in the number of engine cranking in addition to the inherent low emission characteristics of gaseous fuel. Hydrogen, in particular, showed superior performance in comparison to other examined gaseous fuels. The significant number of engine-start using 200 g of gaseous fuel particularly hydrogen makes the gaseous fuel viable to be used together with conventional liquid gasoline fuel.