Reduction of area-wide emissions using an efficient model-based traffic control strategy

In addition to the challenge to reduce traffic jams, reduction of traffic emissions in such a way that the dispersion of the emissions to residential areas, hospitals, schools, and other neighborhoods is decreased is a problem that requires state-of-the-art traffic control and management solutions. In this paper we model the dispersion of the emissions from a freeway traffic using a grid-based approach where the variability of the speed and direction wind is considered into account. The model is developed in such a way that the computation time is less than a previously proposed point-source model, while still capturing the important dispersion dynamics so that it can be used for on-line control applications. In order to reduce the dispersion of emissions to a neighborhood we design a parameterized model predictive control (MPC) strategy to optimize variable speed limits and ramp metering rates. We illustrate the proposed dispersion model and control approach with a simulation-based case study.