道路坡度对重型车PEMS测试影响试验研究

Experimental study on the impact of road grade for a heavy-duty vehicle PEMS test

通过实际道路测试和试验室底盘测功机复现试验的方法,研究道路坡度对重型柴油车实际道路测试结果的影响。试验结果表明:道路坡度直接影响发动机负载状态,从而影响燃油消耗和污染物排放;比油耗和CO_(2)比排放与车辆是否处于坡路行驶无直接关联,基于里程的油耗评估无法全面反映车辆的能效水平;NO_(x)排放受多种因素影响,下坡可能因排温下降而降低选择性催化还原系统效率,导致排放升高,也可能因发动机功耗降低而减少NO_(x)排放。道路坡度是评估重型车辆实际道路排放不可忽视的重要因素。

The effect of road slope is studied on PEMS testing of heavy-duty diesel vehicles through actual road testing and laboratory chassis dynamometer replication tests.The results show that changes in road slope directly affect the engine load state,thereby affecting fuel consumption and pollutant emissions.Although the mileage fuel consumption increases on uphill and decreases on downhill,the specific fuel consumption and CO_(2)emissions are not directly related to whether the vehicle is driving on a slope,and mileage based fuel consumption assessment cannot fully reflect the vehicle′s energy efficiency level.NO_(x)emissions are influenced by various factors.Downhills may result in a decrease in SCR efficiency due to a decrease in exhaust temperature,leading to an increase in emissions,or a decrease in NO_(x)emissions due to a decrease in engine power consumption.In short,road slope is an important factor that cannot be ignored in evaluating the actual road emissions of heavy vehicles.