Inventory and prediction of heavy-duty diesel vehicle emissions.

摘要

A vehicle emissions inventory is an account of emissions produced by all vehicles in an area. Many different factors can affect the emissions and the measurement of the emissions that are used to create an emissions inventory. These factors for heavy-duty diesel vehicles have been addressed and their relative affect on emissions was evaluated from test data and analytical analyses. These elements can affect the emissions by a factor of 15 depending on testing conditions.; One purpose that an emissions database serves is to provide a source for predicting future emissions for a specific vehicle or many vehicles in a general area. Using a database directly for prediction is ideal, but no comprehensive data set currently exists that covers all of the different vehicle and component combinations that exist in current use. Numerical models can be used to take the existing information about vehicle emissions and calculate the emissions that would be produced by all the vehicles in an inventory. The Transportable Heavy-Duty Vehicle Emissions Testing Laboratories at WU have collected emissions data from heavy-duty vehicles for approximately 8 years. This existing data were used in an analysis to develop a method that can produce emissions factors in grams per mile for all heavy-duty vehicles from a small database of measured emissions. The method developed categorizes the emissions according to the vehicle speed and acceleration. The WVU emissions data were combined with truck activity data derived by Battelle Memorial Institute to create emissions factors in grains per mile that reflects actual driving patterns. These factors were then compared to measured emissions from the THDVETL and errors were found to be as low as 5%.