Evaluation Research For Fuel Consumption And Automobile Emissions Based On Vehicle Dynamics

In twenty-first Century,global environment emphasizes sustainable development,people were enjoying the convenience of the perfect road infrastructure and the influence of the decrease of the air quality caused by the exhaust emission of motor vehicles.As a region with high ecological sensitivity in mountain areas,the construction of mountain highways was subject to its special terrain and landform.Under the basic premise of guaranteeing quality and safety,through scientific management and technological progress,the quantitative assessment of exhaust emission and fuel consumption in different road alignment should be carried out in order to save the resources and reduce the negative impact on the environment.Based on the engine power and speed of motor vehicle in micro traffic simulation model are not changed with road alignment,the micro traffic simulation model VISSIM,the vehicle dynamics model CarSim and the micro emission model CMEM are combined,and the operation output data of the micro traffic simulation model VISSIM is used for the speed control of CarSim.A vehicle dynamic based vehicle fuel consumption and tail gas evaluation method is proposed.Based on the fact that the traditional micro traffic simulation model VISSIM does not change the power and speed of the engine with the change of the geometric characteristics of the road,the simulation method of combining the micro traffic simulation model VISSIM and the vehicle dynamics model CarSim is proposed,which can be used to get the vehicle operating data which is more in line with the actual situation.The information of the Taimei Road section of Xi'an City,which is selected in this paper is collected and processed.The road model is established in VISSIM and CarSim respectively.At the same time,using the running speed data of the test vehicle to calibrate the vehicle expected speed in VISSIM,and establish the vehicle model and driver in the CarSim.Finally,we use micro emission model CMEM to calculate vehicle emission and fuel consumption.Compared with the integrated simulation method H-3 and the single simulation method H-1,the emission and fuel consumption reduction range of the road section is 3.5%-6.9%.Compared with the integrated simulation method H-4 and the single simulation method H-2,the increase of exhaust emission and fuel consumption is 14.5%-55.8%.Compared with the integrated simulation method T-3 and the single simulation method T-1,the emission and fuel consumption reduction range of the Tai coal road section is 13.2%-16.9%.Compared with the integrated simulation method T-4 and the single simulation method T-2,the increase of exhaust emission and fuel consumption is 33.5%-57.1%.The results show that the two simulation methods have different exhaust emissions and fuel consumption results,the hypothetical road section difference is small,and there is a bigger difference on continuous curves and inclination combinations.It shows that the simulation method proposed in this paper is more accurate for the simulation of vehicle operating conditions under different road character.It is clear that curvature and inclination of road are the important factors that affect exhaust emissions and fuel consumption,and inclination has greater impact on exhaust emissions and fuel consumption.At last,using the Geographic Information System(GIS)for the segment of Taimei Road to express intuitively.