A Review on the Dispersion Models for the Automobile Emissions

Abstract

Since the 1970s, many experiments have been conducted on automobile emissions and many dispersion models have been proposed. Although the series of experiments being conducted by GM are the most comprehensive in this field, the experiments being performed in Japan may surpass those in the U.S. both in terms of number and scale. In this review paper, we discuss the recent progress made in the development of automobile emission dispersion models, examine their effectiveness, and look at the more important studies that have been conducted.
The following were examined:
1. Studies on automobile emission dispersion based on data obtained through experiments, and which include the following categories: concentration distribution of pollutants in the vertical direction; vertical spread of automobile emissions σ_z; initial vertical spread of automobile emissions σ_z0; roadside wind conditions; dispersion of pollutar ts in the street canyon; dispersion of pollutants from the entrance/exit of tunnels; effects of road configuration on the dispersion of pollutants.
2. Discussion regarding hitherto proposed dispersion models for predicting pollutant concentration. Evaluation of above models.