Fuel economy and exhaust emissions of a diesel vehicle under real traffic conditions

Traffic and vehicle simulations are often developed individually. However, vehicle performance is heavily affected by traffic conditions. Cosimulations of traffic and vehicle under real-road situations can reflect the semi-real-world performance of vehicles, with traffic conditions being taken into considerations. This paper proposed an approach to combine the traffic and vehicle simulations that are realized by simulation of urban mobility (SUMO) and GT-Suite software, respectively. In this paper, the sensitivities of the road grade and vehicle speed to the fuel economy and exhaust emissions were investigated; vehicle fuel consumption and regular exhaust emissions on a real-road were analyzed; the effect of the traffic accident and congestions on fuel consumption and exhaust emissions were quantified. The results indicated that nitrogen oxides (NOx) and soot emission were consistent with fuel consumption rate, which was dominated by vehicle acceleration whose effect was aggravated by road grade. The fuel penalties caused by accident were in the range of 0.015-0.023 kg depending on the severity of the accidents. The fuel consumption increased from 1.199 to 1.312 kg and 1.559 kg for 900 and 1800 vehicles/h traffic flow cases compared with 180 vehicles/h traffic flow.