HEAVY-DUTY DIESEL ENGINE FUELS COMBUSTION PERFORMANCE AND EMISSIONS - A COOPERATIVE RESEARCH PROGRAM.

A cooperative research program has been completed evaluating the impact of fuel composition (volatility, aromatics and sulfur) on the combustion and emissions performance of a Caterpillar 3406B turbocharged diesel engine. Tests included both steady-state and transient operation measuring regulated and unregulated emissions. In steady-state emission tests, the data indicate that changes in the volatility or aromatic content had no substantial effect on particulates, smoke emissions, or gaseous emissions except NO//x. Increasing aromatic content increased NO//x emissions. Sulfur content had the expected impact of increasing the weight of particulate emissions but had no evident effect on the smoke opacity. Transient testing did not change any trends except for the effect of aromatic content on HC, particulate, and smoke emissions; increasing aromatic content increased these emissions.