道路坡度对轻型车和重型车尾气排放的影响研究

Study on Influence of Road Slope on Exhaust Emission of Light and Heavy Vehicles

道路坡度是建立车辆排放模型和选择生态路线的重要因素,然而由于坡度数据采集难度较大,在车辆排放模型构建和车辆导航系统的路径优化中往往被忽略.文中以CO_(2)和NO_(x)两种典型的车辆尾气为例,分别研究了路面坡度对轻型车和重型车尾气排放的影响,论证了路面坡度的重要性.车辆尾气排放数据由OBEAS-3000便携式排放测试仪采集,道路坡度使用车载GPS记录的高程数据进行估计.研究结果表明:在-5%~5%的坡度范围内,两种车型的CO_(2)和NO_(x)排放量均随路面坡度的增大呈现上升趋势;特别是当路面坡度大于1%时,两种气体的排放量随坡度增大快速增长.此外,轻型车辆的排放对道路坡度更为敏感,而重型车辆尾气排放的绝对增量远大于轻型车辆,忽略道路坡度会导致车辆尾气排放估计误差,尤其是对轻型车尾气排放影响较大.因此,在车辆尾气排放评估和生态路径选择规划中,不应忽略道路坡度的影响.

Road slope is an important factor in building vehicle emission model and selecting ecological route.However,due to the difficulty in collecting slope data,it is often ignored in building vehicle emission model and optimizing the path of vehicle navigation system.Taking CO_(2)and NO_(x),two typical vehicle exhaust gases,as examples,this paper studied the influence of road slope on the exhaust emissions of light and heavy vehicles,and demonstrated the importance of road slope.The vehicle exhaust emission data was collected by OBEAS-3000 portable emission tester,and the road slope was estimated by the elevation data recorded by vehicle GPS.The results show that within the range of-5%~5%slope,the CO_(2)and NO_(x) emissions of the two vehicle types are increasing with the increase of road slope.Especially when the road slope is greater than 1%,the emissions of the two gases increase rapidly with the increase of slope.In addition,the emission of light vehicles is more sensitive to road slope,while the absolute increment of exhaust emission of heavy vehicles is much larger than that of light vehicles.Ignoring road slope will lead to the estimation error of vehicle exhaust emission,especially for light vehicles.Therefore,the influence of road slope should not be ignored in vehicle exhaust emission assessment and ecological path selection planning.