反应机理对湍流预混值班火焰稳燃影响的研究

针对反应机理对湍流预混值班火焰稳燃的影响,使用大涡模拟(LES)耦合输运概率密度(PDF)方法模拟了湍流射流火焰的燃烧流场。化学反应过程采用被广泛应用的SMOOKE (16组分,46步)和DRM22 (22组分,104步)机理,概率密度输运的确定采用欧拉随机场来实现。计算结果表明,LES/PDF模型可以准确地模拟该类火焰的速度分布,火焰褶皱等结构。反应机理的点火延迟时间的准确与否是模拟值班射流火焰的关键,预混射流出口处的小尺度掺混引起的点火和火焰传播过程是值班射流火焰稳燃的关键。

Effects of Reaction Mechanism on Stabilization of Turbulent Premixed Pilot Flame

Aiming at the effects of different reaction mechanisms on the flame stability, LES coupled transport probability density (PDF) method were used to simulate the combustion flow field of turbulent jet flame. The chemical reaction process uses SMOOKE (16 components, 46 steps) and DRM22 (22 components, 104 steps) mechanism which are widely used, and the probability density transport equation is achieved by Eulerian stochastic fields method. The results show that the LES / PDF model can accurately capture the velocity distribution, flame wrinkle and other small structures. The prediction of ignition delay time is the key factor to accurately simulate the pilot jet flame, and the auto-ignition and flame propagation process caused by small scale mixing at exit of jet are main mechanism of flame stability.