Time-Resolved Measurement of Speciated Hydrocarbon Emissions During Cold Start of a Spark-Ignited Engine 940963
Speciated HC emissions from the exhaust system of a production engine without an active catalyst have been obtained with 3 sec time resolution during a 70°F cold start using two control strategies. For the conventional cold start, the emissions were initially enriched in light fuel alkanes and depleted in heavy aromatic species. The light alkanes fell rapidly while the lower vapor pressure aromatics increased over a period of 50 sec. These results indicate early retention of low vapor pressure fuel components in the intake manifold and exhaust system. Loss of higher molecular weight HC species does occur in the exhaust system as shown by experiments in which the exhaust system was preheated to 100° C. The atmospheric reactivity of the exhaust HC emissions for photochemical smog formation increases as the engine warms.
Citation: Kaiser, E., Siegl, W., Baidas, L., Lawson, G. et al., "Time-Resolved Measurement of Speciated Hydrocarbon Emissions During Cold Start of a Spark-Ignited Engine," SAE Technical Paper 940963, 1994, https://doi.org/10.4271/940963. Download Citation
Edward W. Kaiser, Walter O. Siegl, Lanise M. Baidas, Gerald P. Lawson, Carl F. Cramer, Kelvin L. Dobbins, Paul W. Roth, Michael Smokovitz
Ford Motor Co.
International Congress & Exposition
Advanced Developments in Ultra-Clean Gasoline-Powered Vehicles-PT-104, New Technologies for Low Emissions Vehicle Testing-SP-1014, SAE 1994 Transactions: Journal of Fuels and Lubricants-V103-4