湍流燃烧概率密度函数(PDF)模拟的敏感性分析

Sensitivity Analysis in Transported PDF Simulations of Turbulent Combustion

针对采用概率密度函数(PDF)方法的湍流燃烧数值模拟,基于已有的颗粒层面局部敏感性分析,提出一种改进方法,以高效地估计对反应动力学参数的局部敏感性系数。该方法的两个关键思路为:评估化学反应对组分演化的重要程度;以"当前效应"估计"总体效应"。以部分搅拌反应器(PaSR)为研究对象,通过与直接计算的结果比较,证明了新方法的计算结果可作为直接计算的有效估计,能够有效预测各个化学反应对于系统的相对重要性。

For transported probability density function（TPDF） simulations of turbulent combustion,a highly efficient particle-level sensitivity analysis approach is proposed to compute the sensitivity of simulation results with respect to the chemical kinetic parameters.The two key steps in the approach are：1） quantify the importance of chemistry in the species evolution;2） approximate the solutions to particle sensitivity equation by neglecting its historic contribution.The newly proposed approach is applied to simulations of a partially stirred reactor（PaSR）,and it is found that this approach is capable of predicting the relative importance of different reactions to the system.