Performance and emissions of a spark-ignition engine fuelled with lower calorific gases (basic combustion characteristics of individual gas component)

This paper presents basic combustion characteristics of a spark-ignition engine fuelled with three kinds of gaseous fuels ; H2, CO and CH 4. A single-cylinder engine was operated under WOT at 1 500 min -1 condition, CO gas gives lower thermal efficiency than H 2 and CH4, since the energy of the fuel can not be transferred to the pressure or the work, although it gives higher combustion temperature which makes the higher exhaust gas temperature and much higher NOx emissions than those for CH4. H2 gives upper limit of flammability due to the occurrence of backfire and almost comparable thermal efficiency with that for CH4 at its stoichiometric condition.