| Heavy-duty diesel engines are known to emit concentrations of harmful compounds of oxides of nitrogen (NOx) and particulate matter (PM). As a means of emissions control, engine dynamometer certification is currently employed. Current certification cycles provide for standardized comparisons, but may not be indicative of real-world emissions. Accurate in-use emissions testing would provide more realistic engine emissions values.; To examine the accuracy of the West Virginia University Mobile Emissions Measurement System (MEMS), on-road emissions tests were performed with six different diesel-powered vehicles. Exhaust species measured by MEMS were NO x and CO2, reported on a brake-specific basis. Information obtained during on-road emissions tests was implemented in the creation of a simulated in-use engine dynamometer cycle, and the system was compared against an engine dynamometer laboratory.; The ability to accurately generate an in-use driving cycle for an engine dynamometer was studied, and variables affecting route repeatability were measured. (Abstract shortened by UMI.)... |
