Effects Of Route Guidance Strategies On Traffic Emissions In Intelligent Transportation Systems

With the rapid development of urban traffic,environmental pollutions caused by traffic couldn’t be ignored any more.One of the two main factors for the traffic emission increase was the increases of the total number of motor vehicles,and the other one was the traffic congestion.The promotion of electric vehicles could reduce the emissions caused by the increase in the number of conventional oil-fueled vehicles,and an effective route guidance strategy could reduce traffic congestions.So this paper studied the conventional oil-fueled vehicles and electric vehicles’ effects of different route guidance strategies on traffic emissions in intelligent transportation systems.We took conventional oil-fueled vehicles and electric vehicles as our simulation objects,and applied six route guidance strategies in four different two-route scenarios models(The symmetrical tworoute scenario with two exits,the symmetrical two-route scenario with exit,the asymmetrical two-route scenario with two exits,and the asymmetrical two-route scenario with one exit).The real data of traffic emissions under different vehicle operational modes were used.The simulations of the traffic emissions,the emissions per vehicle,the emissions per unit flux,average travel time per vehicle and the relationship between the emissions per unit flux and the ratio of dynamic vehicles by using six route guidance strategies were obtained.Results showed that no matter was conventional oil-fueled vehicles or electric vehicles,mean velocity route guidance strategy(MVS)and congestion coefficient route guidance strategy(CCS)were the best ones.They can effectively reduce the traffic emissions and improve the efficiency of traffic network.In terms of the total emissions,the value of emissions on the symmetrical two-route scenario with two exits was much lower than that on the one with one exit.Compared the emissions of conventional oilfueled vehicles and electric vehicles,it could be seen that electric vehicles could reduce some kind of certain pollutants,such as NO,while it could also lead to the increase of certain pollutants,such as HC.Finally,we drew three conclusions based on the simulation results: i)The route guidance strategy based on traffic data of the whole road is beneficial to reduce traffic emissions.ii)The simpler and smoother road can lead to more reduction of traffic emissions and higher efficiency of traffic network.iii)In China’s current energy structure,promoting electric vehicles in areas with smaller thermal power generation can effectively reduce the traffic emissions.