为研究发动机“恒转增扭”瞬变工况下的微粒排放特性及优化方法，以车用2.8 L增压柴油机为研究对象，首先研究了单因素喷射参数对柴油机瞬态加载工况微粒排放的影响；随后设计了田口正交试验，给出以微粒数量及质量为输出指标的最优控制参数组合，并确定了各控制参数的影响权重。结果表明：在瞬变加载过程中，小尺寸核态颗粒物数量浓度恶化明显，大尺寸聚集态颗粒物质量浓度显著恶化；适当地将主喷时刻提前、增大轨压以及引入恰当的后喷可降低微粒排放；同时，控制参数对核态和聚集态微粒的影响存在Trade-off关系，对微粒排放影响权重相对较大的均为喷油时刻的影响，即喷油正时和主后喷间隔。

To study the particulate emissions characteristics and optimization methods of the engine under transient conditions， takes a 2.8 L turbocharged diesel engine as the research object. Firstly， the effects of single factor injection parameters on the particulate emissions under transient loading conditions were studied. Then，Taguchi orthogonal experiment was designed to give the optimal control parameter combination with the number and quality of particles， and the influence weight of each control parameter was determined. The results show that during the transient loading process， the number and concentration of small-sized nuclear particles deteriorated significantly， and the mass concentration of large-sized accumulated particles deteriorated significantly； Appropriately advancing the injection timing， increasing the injection pressure and the introduction of post-injection can reduce particulate emissions； Meanwhile， the effect of control parameters on nuclear and accumulated particulates has a trade-off relationship， and the relatively large weight of particulate emissions is the effect of fuel injection timing， that is the factor of injection timing and post injection interval.