基于特征值分析法,建立了一套复杂化学反应动力学模型简化方法,并采用该方法对甲烷空气燃烧的详细化学反应动力学模型进行了简化.从GRI1.2得到了21个组分,83个反应的骨架机理.该机理与详细的GRI1.2机理和DRM19机理在不同化学计量比和不同压力下对比了点火延迟时间,结果表明简化机理能有效地再现详细反应动力学模型的反应机理,并具有更高的计算精度.从GRI3.0简化得到两种骨架机理分别为26个组分、120个反应和30个组分、140个反应.这两个机理都能很好地对火焰传播速度以及主要组分和NO浓度分布进行反应动力学模拟.
A new eigenvalue analysis-based method is presented for the construction of skeletal reduced mechanisms from complex chemical reaction mechanisms. A reduced mechanism of 21 species and 83 elementary reactions for methane-air combustion was generated from detailed mechanism GRII.2. The ignition delay time, obtained for different values of equivalence ratio, initial temperature and pressure on the basis of this reduced mechanism, were compared with those based on the detailed mechanism GRI1.2, and another skeletal mechanism DRM19. The reduced mechanism agreed favorably with the detailed model, and performed more accurately than DRM19. Two reduced mechanisms, the first involving 120 reactions among 26 species, the second, 140 reactions among 30 species, were also generated from GRI3.0. They were tested by means of premixed laminar flame calculations. The method very accurately predicted concentration distribution speed of flame propagation and key species concentration and even NO n methane combustion.