EXPERIMENTAL INVESTIGATION AND OPTIMIZATION OF SYNTHETIC BIOGAS INTAKE AND MIXING REGIMES IN DUAL-FUEL RCCI COMBUSTION

The measures for addressing nitrogen oxides (NOx) and soot (PM) in reactivity controlled compression ignition (RCCI) combustion cause increased unburned hydrocarbon (UHC) and carbon monoxide (CO) emissions. The gaseous biofuel
combustion still causes hazardous emissions and a contradictory trend between the CO and UHC in RCCI. Disparities in biogas constituents and high inert content pose
combustion control challenges. Modified port fueling and systematic understanding of how biogas containing high carbon dioxide (CO2) reduces peak pressure rise rate (PPRR), CO, and UHC emissions at low loads still require more effort in RCCI research. This experimental study examines the impact of high-CO2 biogas and direct injected fuels to improve combustion and reduce hazardous emissions at various engine loads (4.5 – 6.5 bar IMEP) and speeds (1600 – 2000 rpm).