In this paper, the laminar combustion characteristics of n-heptane/carbon dioxide/air flames are numerically investigated by using the Chemkin/Premix Code and LLNL v3.1 mechanism. The equivalence ratios vary from 0.8 to 1.4 at the initial temperature of 298 K. The initial pressure is set as 1, 2, 5, 10, 20 atm. Laminar burning velocity (LBV), adiabatic flame temperature (AFT), net heat release rate (NHRR) and the mole fractions of H, O, OH, CO at stoichiometric ratio are studied with carbon dioxide (CO₂) addition. Meanwhile, temperature sensitivity and rate of production (ROP) are analyzed. In addition, the physical and chemical effects of CO₂ are investigated by introducing fictitious carbon dioxide (FCO₂).The results show that with the increase of initial pressures, LBV decreases, AFT and NHRR increase, the peaks of intermediate products such as H, O, OH and CO decrease. The promoting effect of elementary reactions on temperature is greatly enhanced, while the inhibiting effect is slightly enhanced. With the increase of CO₂ doping ratios, LBV, AFT and NHRR decrease, while the peaks of H, O, OH, CO increase first and then decrease. The promoting and inhibiting effects of elementary reactions on temperature are enhanced. Both physical and chemical effects of CO₂ inhibit the combustion of n-heptane, where physical effect dominates. The total ROPs of H, O, OH change from consuming to producing, while the total ROP of CO is opposite.

本文利用Chemkin/Premix Code和LLNL v3.1机理对正庚烷/二氧化碳/空气火焰的层流燃烧特性进行了数值研究。当量比在 298 K 的初始温度下从 0.8 到 1.4 不等。初始压力设置为 1、2、5、10、20 个大气压。通过添加二氧化碳 (CO ₂ )研究了层流燃烧速度 (LBV)、绝热火焰温度 (AFT)、净热释放率 (NHRR) 和化学计量比下的 H、O、OH、CO 的摩尔分数。同时，分析了温度敏感性和生产率（ROP）。此外，CO的物理和化学作用₂通过引入虚拟二氧化碳（FCO调查₂).结果表明，随着初始压力的增加，LBV降低，AFT和NHRR增加，H、O、OH和CO等中间产物的峰减少。基元反应对温度的促进作用大大增强，而抑制作用略有增强。随着CO ₂掺杂比例的增加，LBV、AFT和NHRR降低，而H、O、OH、CO的峰值先增加后减小。基元反应对温度的促进和抑制作用增强。CO _{2 的}物理和化学作用都会抑制正庚烷的燃烧，其中物理作用占主导地位。H、O、OH 的总 ROP 从消耗变为生产，而 CO 的总 ROP 则相反。