基于柴油机各缸 EGR 率差异的分缸仿真分析

摘要

利用发动机仿真模拟软件，对电控单体泵柴油机的燃烧过程进行数值模拟分析。通过研究电控单体泵柴油机各缸实际EGR （Exhaust Gas Recycling ，废气循环）率不均匀的成因以及对柴油机燃烧排放的影响，提出柴油机各缸喷油参数分缸标定的优化方案。经过对喷油量和喷油提前角同时进行分缸标定仿真模拟研究，结果表明，分缸标定能有效地解决因柴油机各缸实际EGR率差异导致的柴油机各缸燃烧不均衡的问题，并能有效降低柴油机尾气中SOOT （碳烟）和NOx （氮氧化物）的排放。%By use of engine simulation software ,the combustion process of Electronic Unit Pump (EUP) diesel engine was numerically simulated .Based on the study on the reason for uneven Exhaust Gas Recycling (EGR) rate of EUP diesel engine ,the injection parameters of each cylinder for diesel engine calibration optimization were proposed . The simultaneous calibration of injection quantity and injection timing was carried out by simulation . The results indicate that sub-cylinder diesel engine calibration can effectively solve the combustion imbalance problem in diesel engine’s cylinders ,which is caused ty the differences in each cylinder EGR rate ,and effectively reduce diesel exhaust SOOT and NO x (nitrogen oxide) emissions .