Development of On-Road Emission Factors for Heavy-Duty Vehicles

摘要

The paper discusses an EPA project the objectives of which are to: (1) define on-road emissions from heavy-duty diesel vehicles (HDDVs); (2) assess agreement between engine and chassis dynamometers and on-road emission factors; (3) evaluate current conversion factors for dynamometer data and develop appropriate ones if needed; and (4) develop a model emissions model. The experimental approach involves on-road tests that develop the model data necessary to model the emissions as a function of speed, load, grade, and acceleration. These data are fitted to routes representing trans-urban interstate travel, terminal entry/exit, and urban delivery. A final test sequence utilizes a certification cycle that has been adapted to suit actual truck operational capability to develop data for direct comparison with the dynamometer data.