四冲程汽油机 CAI 燃烧放热率模型研究

通过大量试验数据分析，提出了适用于四冲程汽油机可控自燃（ControlledAutoIgnition，CAI）燃烧的放热率模型。研究发现汽油机CAI燃烧在低温时有少量放热，因此，放热率模型包括两个阶段——低温缓慢自燃阶段和高温迅速放热阶段，与一维发动机模拟软件GT-Power相耦合后在相同试验条件下着火时刻及平均指示压力PIMEP的计算结果与试验结果偏差较小。此模型可用于进行发动机预测、设计以及控制策略的研究。

Study on CAI Combustion Heat Release Model in 4-Stroke Gasoline Engine

In this paper,a model for predicting heat release of the Controlled Auto Ignition(CAI) combustion was proposed based on in-cylinder pressure data.The study showed that small amount of heat release was presented prior to the rapid heat release near the end of compression stroke.Thus,the heat release model should include two parts,the low temperature heat release process and the subsequent high temperature combustion.Calculations show that the deviations in ignition timing and net IMEP are very small compared to those of experimental data by coupling this heat release model with GT-Power programme.The combustion model can be used to prediction,designing and controlling of CAI combustion engine.