汽油机非稳定加速工况燃烧放热率计算模型的修正

要对发动机非稳定工况实施最优控制，就应对其在非稳定工况下的工作过程做深入的研究。求取燃烧放热率是进行燃烧过程优化研究的基本手段，但在迄今为止的各种燃烧分析仪中，给出的多为稳定工况分析结果。作依据４９２Ｑ汽油机加速过程的试验结果，修正了汽油机燃烧放热率计算的热力学模型，使之适用于非稳定工况最后，通过实测示功图分析了４９２Ｑ汽油机沿外特性加速过程的放热特性和指示效率。

Revision on Calculating Model of Combustion Heat Release Rate for Gasoline Engines Under Transient Conditions

Vehicle engines are often performed under the transient operation conditions.By means of high speed data acquisition and analysis of instantaneous cylinder pressure signals etc.,this paper makes the further study on heat release rate calculation of gasoline engines.Based on the test data of acceleration process of 492Q gasoline engine,a thermodynamic model of combustion heat release rate is developed to study the transient behavior of gasoline engines.The characteristics of heat release and cycling thermal efficiency of the 492Q gasoline engine during full load accelerating are analyzed from measured indicator diagrams.