实际行驶工况下柴油车发动机负荷分布及排放

通过发动机电子控制单元测试发动机的转速、油门开度，研究排放满足欧3标准的某重型发动机在北京高速行驶工况下负荷分布特征，并基于发动机台架试验时的负荷特性数据计算出其功率消耗；同时结合车载排放系统的测试结果计算出该工况下的比功率排放量．试验表明，实际道路发动机的负荷分布特征和实验室法规工况差异较大，导致实际工况和法规工况下的排放数据差异大，尤其在NOx和PM两个指标方面．需重新匹配整车和发动机，使其能够工作在高效工作区域；或者采用符合我国实际道路运行工况的法规认证测试方法来控制车辆的道路排放，进而减少城市重型机动车NOx和PM的排放．

Diesel engine load distribution and exhaust emissions under real-world driving condition

Based on the engine load characteristic data,the heavy duty engine exhaust emissions under Beijing Bus high speed driving cycle were studied.Because the engine load is different between ESC13 and real-world test,the results for the lab regular test and PEMS test are very different,especially in NOx and PM.Two methods were presented to decrease the exhaust emissions.The first is that the match must be renewed for the whole car and engine,making the engine work mode fall in the high efficient area;the second is that the test cycle should be modified according to the engine load distribution in China.