Development of Fuel Consumption and Vehicle Emissions Relationships for Congested Freeway Flow Conditions

摘要

Fuel consumption and vehicle emissions are commonly used measures of effectiveness for describing differences between freeway improvement alternatives. However, current sketch planning relationships between fuel consumption and vehicle emissions and parameters that can be measured over time, such as average speed, are inadequate because they use out-of-date assumptions about the vehicle fleet, they do not apply to the entire range of congested freeway operating conditions, and/or they are based on assumed rather than actual vehicle operating patterns. The study examined several types of relationships between fuel consumption and vehicle emissions and various operating parameters, and tested them. The most practical of these relationships use total distance traveled and total travel time as independent variables. These relationships are very highly correlated for both total fuel consumed and total emissions of the three major types of pollutants. These relationships were calibrated for the data used in the study. A computational example of the potential usefulness of the relationships developed is given.