对柴油－天然气掺烧发动机的滞燃期进行了深入研究． 以喷油器针阀升程曲线开始增加时所对应的曲轴转角作为喷油始点，压力升高率急剧变化的点作为燃烧始点，确定发动机滞燃期． 将喷油始点作为计算点，以试验数据为基础，对柴油发动机滞燃期预测模型进行修正，得到柴油－天然气掺烧发动机滞燃期预测模型． 试验结果表明，修正后的滞燃期预测模型能够很好地预测柴油－天然气掺烧发动机滞燃期，可为准确建立柴油－天然气掺烧发动机工作过程数学模型提供指导依据．

This paper deals with the ignition delay of the diesel-natural gas blending engine.This ignition delay isdetermined by taking the crank angle corresponding to the injector needle lift curve rising in the beginning as the injectionstart point and by using the dramatic change point of the pressure rise rate as the combustion start point.Then,with the injection start point as the calculation point and based on the experimental data,an ignition delayprediction model of the diesel-natural gas blending engine is established by revising the ignition delay predictionmodel of the diesel engine.Experimental results show that the revised model can predict the ignition delay of thediesel-natural gas blending engine and helps to establish an accurate working process model for the diesel-naturalgas blending engine.