Comparison Of The Soot Reactivity Of Different Diesel Fuels On A Research Single-Cylinder Engine And On A Multi-Cylinder Production Engine

This study examines the impact of various diesel fuels on exhaust emissions under representative part-load engine operation. Since differences in NOx emissions between fuels are generally minor, the focus is placed on particulate emissions and the corresponding soot reactivity. Experiments were conducted on a single-cylinder research engine and in part validated on a Euro6 multi-cylinder production engine. Regardless of the set operating point, it can be stated that soot emissions are highest when fossil diesel fuel without FAME is used, and that the lowest soot emission occurs when using the HVO / OME blend. The other fuels are in between in terms of soot emissions. This behavior can also be observed in the total particle number concentration. However, this varies depending on the operating point. This is also confirmed by the tests at the multi-cylinder engine. Thermogravimetric analysis was used to determine soot reactivity. With regard to the soot reactivity on the single-cylinder research engine, it can be determined that this is very dependent on the operating point and the differences are accordingly more or less pronounced depending on the fuels used. However, the trends are similar regardless of the operating point. But the variance in soot reactivity due to the fuel formulation is largely determined by the engine setting parameters. The highest soot reactivities were achieved with both engines when using fossil diesel with FAME. In general, soot emissions resulting from oxygenated fuels due to FAME or OME show significant increases in soot reactivity.