Study On The Calculation Method Of Car Carbon Emission Factors On County Roads

With the development of the county economy,the traffic volume of county roads in counties continues to increase so that traffic congestion and carbon emissions are becoming more and more serious.Most of the current traffic emission research is concentrated on the large city or regional level and only a little research is concentrated on county level.Besides,there are few studies on developing models for calculating car carbon emissions based on simple traffic data.Compared with large cities,county roads have fewer classifications and simpler road forms,which greatly improves the feasibility of finding the relationship between car carbon emission factors and traffic variables in limited road forms.In this context,this article combines micro-simulation and popular vehicle exhaust emission model on the market to obtain a large number of car CO2 emission factor datas under different traffic situations,and explore the calculation method of car CO2 emission factor in the basic road network of county towns.First of all,after summarizing the current research status of the research on traffic emission estimation and the combined application research of traffic simulation and motor vehicle exhaust calculation model,it is found that there are few researches on CO2 emissions focusing on county traffic.Compared with other modes of transportation,the CO2 emissions of cars accounted for the highest proportion in county area,and the current urban roads lack a universal and simple calculation model for the CO2 emission factor of cars,which puts forward the necessity of this study.Secondly,the VISSIM simulation model and the MOVES model are calibrated based on the vehicle ownership data and traffic characteristic data of the surveyed counties.During the calibration process,the influence of some calibration parameters on the calculation results of the CO2 emission factor of car traffic is also analyzed.Thirdly,the 12 basic road network types selected in the survey are studied.For each basic road network type,simulation is performed by changing a variety of different road section lengths and traffic volume to obtain the key input parameter average travel speed in the motor vehicle exhaust calculation model.The speed parameter is used to calculate the CO2 emission factor of the car in each situation through the MOVES model.In addition,based on the large amount of car CO2 emission factor data obtained,the correlation analysis between the car’s CO2 emission factor and the traffic variables set in the simulation is carried out,and the influencing variables in the car’s CO2 emission factor calculation model are obtained.Then the data was modeled by multiple linear regression and multiple non-linear regression respectively,and the model form with the highest degree of fit was selected through comparison.After that,the sensitivity of the variables in the calculation model was analyzed.Finally,take the four counties of Changxing,Qingcheng,Jintang,Wu’an as examples.After obtaining the traffic distribution data of the four counties through traffic demand analysis,the calculation model in this article is used to calculate the CO2 emission factor of the cars in each road segment of the commuting period in the urban areas of the four counties and the average CO2 emission factors of cars in the road network during commuting periods of the four counties.