根据排放成分确定空燃比的研究

Research on Air Fuel Ratio Model Based on Vehicle Emission

介绍了由发动机尾气排放物求空燃比精确解的模型 ,分析了进气湿度和温度、气体分析仪精度、NOx 浓度等对Φa 计算值的影响。通过简化模型 ,得到了空燃比的使用计算公式 ,并给出了实际分析数据和对比结果。简化计算模型仅需 φCO、φCO2 、φO2 、φH C的数值就可计算空燃比 Φa,该模型可用于替代燃料的空燃比计算。同时给出了理论空燃比和过量空气系数的计算通式。目前的 4气、5气分析仪采用本文介绍的Φa和理论空燃比模型改造 ,即可用于替代燃料的Φa和α的测量。运用灵敏度法分析了各种气体测量误差对

An air fuel ratio model based on vehicle emission is introduced.The influence of ambient relative humidity and temperature,water gas equilibrium constant,NO x concentration,error of measuring device is analyzed.A simplified model is reached by omitting some factors having little contribution to Φ a.Some contrast results are provided based on measuring data collected from references.The simplified model only needs data of φ CO ,φ CO 2 ,φ O 2 ,φ HC ,it can be widely adopted by 4/5 gas analyzer.Some information about alternative fuels is put forward,and the simplified model is also suitable for them.