电场作用下火焰中离子对燃烧反应速率的数值模拟研究

Numerical Study About the Ions Effect to the Combustion Reaction Rate Under the Eclectic Field

本文针对甲烷-空气预混火焰中离子对火焰化学动力学特性的影响开展了理论模拟研究。在不同外加电场作用条件下,分析了离子从火焰面区域迁移到低温预热区时对当地化学反应的影响规律。研究表明,低温区内(～800 K)离子对反应速率的影响较大,甚至反应时间可减少65%,而对于1200 K以上高温区该影响则可忽略。实验结果进一步揭示了电场对旋流火焰的影响主要是通过离子风效应改变了火焰面位置和形状而造成的。

This paper numerically studies the effect of chem-ions on reaction kinetics in a premixed methane-air flame. Under different electric field conditions, we investigate the local reaction characteristics affected by the ions which are transferred from flame surface to preheat zone. The results indicate that the ions exhibit, strong influence to the reaction rate under the low temperature（～800 K）, and dramatically shorten the reaction time up to 65%. However, the influence becomes weak when temperature is above 1200 K. It is further divulged from the experiment that the electric field changes the shapes and positions of swirl flame structure via the ionic wind effect.