Modeling and simulation of CO2 emissions in roundabout intersection

Abstract

Traffic control at intersections in urban conditions directly influences the CO2 emissions in their proximity. Improving traffic control at an intersection is another way to reduce vehicular emissions and creating a positive impact on the environment. Roundabout intersection excepted to reduce the CO2 emissions as a result of reducing the vehicle idling time and delays. The purpose of this paper is to investigate the CO2 emissions in a roundabout intersection using a cellular automata model. The roundabout system is composed of the circulating lane and entry/exit lanes, where the entry/exit lanes are controlled by a set of traffic signals (Sn) operating in a fixed-time T. We explore numerically the dependence of the total CO2 emission rate on the injection and extraction rates. Surprisingly, even a small number of vehicles that break the rules of entrance to the circulating lane can affect the CO2 emissions on the roundabout system. Furthermore, we found that the variation of the number Sn, as well as the cycle time play an important role in the variation of the CO2 emissions. Macroscopic and microscopic analyses are conducted to understand the effect of the various parameters on the CO2 emissions in the roundabout system.