基于敏感性分析和准稳态假设简化详细反应机理

Simplification of Detailed Reaction Mechanism Based on the Sensitivity Analysis and Quasi-steady State Assumption

发展了一套基于敏感性分析和准稳态假设来简化复杂化学动力学机理系统的方法。采用等压均相反应器燃烧模型和详细化学动力学机理计算特定工况下的自燃过程。通过对详细机理计算结果的敏感性分析后删除其中的冗余组分和冗余反应,简化得到基干反应模型。再找出基干机理中反应速率较快,浓度较低的组分假定为稳态组分,使用准稳态假设方法简化得到总包反应模型。最后以甲烷燃烧的GriMech1.2详细机理为例分析得到了简化机理并计算了着火延迟时间,与详细机理所得的结果进行比较验证,得到了较好的结果。

A method based on the sensitivity analysis and quasi-steady state assumption was systematically developed in this paper to simplify complex reaction mechanisms. A constant pressure homogeneous reactor model and a detailed reaction mechanism were adopted to calculate the auto-ignition process under the interested condition. Then the result obtained with the detailed mechanism was analyzed through the sensitivity analysis and the redundant species and reactions were identified and deleted from the detailed mechanism to form the skeletal mechanism. After that, the quasi-steady state species （QSSS） which were very small and fast were also found from the skeletal mechanism. The global reaction mechanism was derived with some matrix relations from the skeletal one. Finally, the detailed mechanism GriMechl. 2 for methane oxidization was simplified to form skeletal and global mechanism as an example, and the result was validated with a comparison with the one obtained with the detailed mechanism.