扩散—热和气体动力学不稳定性对管道中预混火焰形状的影响

EFFECTS OF THERMOS-DIFFUSION AND GAS-DYNAMIC INSTABILITIES ON PREMIXED FLAME SHAPE IN PIPELINE

研究预混火焰在圆管或平行通道中的传播 ,对许多工业燃烧装置或系统的安全操作和实际应用都具有重要的意义。扩散—热效应、气体动力学效应和体积力效应是造成预混火焰固有不稳定性 ,改变预混火焰形状和传播特性参数的重要原因。针对管道中预混火焰的扩散—热不稳定性和气体动力学不稳定性 ,以及网眼状火焰和郁金香状火焰的形成作了详细的阐述 ,揭示了火焰形状形成与不稳定性之间的密切关系 ,并得出了重要结论 :扩散—热不稳定性和气体动力学不稳定性分别对网眼状火焰和郁金香状火焰的形成起着决定性的作用。

It is very important to study the propaga-tion of premixed flame in a round tube or parallel channels for the safe operation and application of many industrial combustion facilities and systems. The thermos-confusion effect, gas-dynamic effect and volume-force effect is the major factors to cause the inherent instability of premixed flames, and change the premixed flame shape and its propagating parameters. Aiming to the thermos-diffusion instability and the gas-dynamic instability of premixed flames, the article describes the formation of cellular flame and tulip-shaped flame, reveals the close relationship between the flame shape and the instability, and concludes that thermos-diffusion instability and gas-dynamic instability have great effects on the formations of cellular flame and tulip-shaped flame respectively.