Numerical analysis on the effects of CO2 dilution on the laminar burning velocity of premixed methane/air flame with elevated initial temperature and pressure
Numerical analysis on the effects of CO2 dilution on the laminar burning velocity of premixed methane/air flame with elevated initial temperature and pressure
复制标题
CO2稀释对初始温压升高的甲烷/空气预混火焰层流燃烧速度影响的数值分析
DOI：
10.1016/j.fuel.2019.116858
复制
发表时间：
2020
期刊：
影响因子：
7.4
通讯作者：
Dongjian Zeng
中科院分区：
文献类型：
--
作者：
Mingke Xie;Jianqin Fu;Yongxiang Zhang;Jun Shu;Yinjie Ma;Jingping Liu;Dongjian Zeng
理解CO2稀释对层流预混火焰的不同影响是燃烧控制的有效策略。因此，化学动力学模型的层流燃烧速度（LBV）的CH 4/空气/CO2混合物耦合与详细的化学反应机理的研究在很宽的初始条件下。经过验证和比较，选择了FFCM 1.0进行本研究。在LBV数值预测的基础上，采用解耦方法分离了稀释剂CO2的稀释效应、热效应和化学效应，结果表明，初始温度的升高有利于稀释效应、热效应和化学效应的发挥，而压力的升高则相反。为了从物理和化学上解释这一特殊过程，采用参数分析、灵敏度分析和摩尔分数分析方法，分别证明了单位燃料对LBV的提高、相关热力学参数和重要活性基团对这三种效应的影响。此外，随着温度和压力的变化，有助于化学效应的畴反应分别是反应（R32）和（R62）。通过这项工作，不仅完成了CO2稀释对层流预混火焰影响的研究，而且将通常探索的初始条件扩展到了更宽的范围，为废气再循环（EGR）运行条件和强度设置的研究提供了参考。
Abstract Understanding the different effects of CO2 dilution on the laminar premixed flame is an effective strategy for combustion control. Thus, a chemical kinetic modeling study of laminar burning velocity (LBV) for CH4/air/CO2 mixtures coupling with a detailed chemical reaction mechanism was employed under a wide range of initial conditions. After validation and comparison, the FFCM 1.0 was selected for this study. Based on the numerical prediction of LBV, the decoupling method was carried out to separate the effects of diluent CO2, including dilution, thermal and chemical effects, whose variations show that the rising initial temperature facilitates the three effects whereas the elevated pressure shows the opposite impact. In order to explain the particular process physically and chemically, the parameters analysis, sensitivity analysis and mole fraction analysis methods were conducted, and the LBV enhancement made by per unit of fuel, relevant thermal parameters and the important active radicals were proved to be responsible for the variation of the three effects, respectively. Furthermore, the domain reactions contributing to chemical effect are reactions (R32) and (R62), respectively, as temperature and pressure vary. Through this work, it not only completes the research on the effect of CO2 dilution on the laminar premixed flame, but also expands the commonly exploring initial conditions to a wide range, which provides the reference for the research on the operation condition and intensity setting of exhaust gas recirculation (EGR).