Modeling study of combustion and pollutant formation in HCCI engine operating on hydrogen rich fuel blends

• 2D CFD simulation of combustion and emission characteristics of HCCI engine is conducted.
• CH4, syngas, CH4/H2 and CH4/syngas blends were considered as a fuel.
• Replacement of CH4 by CH4/H2 blend increases output energy and decreases substantially CO emission.
• The usage of CH4/syngas blend improves HCCI performance and reduces the pollutant emissions.
• Addition of a certain amount of H2 or syngas to CH4 can decrease NO emission.

Comprehensive analysis of combustion and emission characteristics of HCCI engine operating on alternative fuels, including methane, syngas, methane/hydrogen and methane/syngas blends is conducted on the basis of CFD simulation with the use of detailed reaction mechanism. It is shown that the replacement of methane to methane/hydrogen blend with 50% H2 volume content makes it possible to increase the output energy during HCCI combustion and simultaneously to reduce the NO and CO emissions. The use of methane/syngas blend as a fuel also leads to an improvement of HCCI performance and to reducing the pollutant emissions, including the emission of CO2.