Understanding the performance of the multiple injection gasoline partially premixed combustion concept implemented in a 2-Stroke high speed direct injection compression ignition engine

摘要

The newly designed Partially Premixed Combustion (PPC) concept operating with high octane fuels like gasoline has confirmed the possibility to combine low NOx and soot emissions keeping high indicated efficiencies, while offering a control over combustion profile and phasing through the injection settings. The potential of this PPC concept regarding pollutant control was experimentally evaluated using a commercial gasoline with Research Octane Number (RON) of 95 in a newly-designed 2-Stroke poppet valves Compression Ignition (Cl) engine for automotive applications. Previous experimental results confirmed how the wide control of the cylinder gas temperature provided by the air management settings brings the possibility to achieve stable gasoline PPC combustion at low and medium speed conditions (1250-2000 rpm) for the whole load range (3.1-10.4 bar IMEP) with good combustion stability (Coefficient of Variation (Coy) of IMEP below 3%), high combustiOn efficiency (over 97%), and low NOx/soot levels.