Experimental Comparison of Gasoline Compression Ignition and Diesel Combustion in a Medium-Duty Opposed-Piston Engine

The Achates Power Inc. (API) opposed-piston (OP) engine architecture provides fundamental advantages that increase thermal efficiency over current poppet valve 4 stroke engines. In this paper, the combustion performance of diesel and gasoline compression ignition (GCI) combustion in a medium-duty, OP engine are shown. By using GCI, NOx and/or soot reductions can be seen compared with diesel combustion at similar or increased thermal efficiencies. The results also show that high combustion efficiency can be achieved with GCI combustion with acceptable noise and stability over the same load range as diesel combustion in an OP engine.