Research On Emissions Model Of Urban Public Transport

The public transportation priority is the current our country municipal transportation trend of development. Because of our country public transport operation course is long, the speed low, adds the deceleration and the idling regime is frequent, the seating capacity is high, its pollutant discharge is prominent. Therefore, study the bus emission discipline and the public transportation emissions prediction model is particularly essential. This article begins from the pollutant discharge principle, established the emissions model which applicable to the operating public transport vehicles, quantitative bus pollution, and provided the necessary theoretical basis for.the greatest degree of reduction of urban public transport pollution in the future.This article on the basis of analysis of our country public transport's movement characteristic foundation and public transport's pollutant formation mechanism, has analyzed the public transport pollutant discharge characteristic. According to the process of burning fuel in the engine, factors which affect the power consumption were divided into the engine, fuel consumption and pollutant emissions of the three processes. Later, According to may or not easy quantitative investigation to divide two categories, study the role of factors, and summarize the key factors as the variable parameters of the predict model.Take the summarized key parameters as input variables, according to the pollutant formation mechanism, we divide the whole process into four process module, include power consumption, fuel consumption, engine emissions, and catalytic after treatmen. And select the simulation calculations were carried out numerical simulation of the four modules, eventually we get the predicting bus emissions model which takes the NOX, HC and CO as the output variable. Use of public transport vehicles operation law on the road rules, accordance with its bus station, the whole bus lines is divided into several sections, every section composite with the station process and the process of running, simplified the two driving conditions, take its total emissions of pollutants are able to calculate, eventually complete the line emissions prediction model.Use the existing equipment to establish the dynamic vehicle emissions testing system which meet the test requirements, design the pollutants emission test under buses running in the actual road, test the bus emissions mode and line emissions prediction model, to prove the two model can rediction the actual diesel fuel bus emission in effect.