Study on Flame Dynamics of Premixed Flames with Controlled Curvature by Laser Irradiation Method

研究了给定初始曲率的预混火焰在激光外照射下火焰不稳定性的演化过程。首先将该方法应用于开放式平板火焰燃烧器，实验揭示了刘易斯数对弯曲火焰生长速率的影响。随着Le的降低，生长速率明显增大。在传播管实验中，研究了声场与弯曲火焰的相互作用。在此基础上，重新定义了无量纲数脉动弗劳德数Gp，并得出了用无量纲数可以给出声场自湍流判据的结论。

Evolution of flame instability of premixed flame with a given initial curvature by external laser irradiation method was investigated. At first the method was applied to open flat flame burner and the effect of Lewis number (Le) on the growth rate of curved flame was experimentally revealed. The growth rate was apparently larger with lower Le. In experiments with propagation tube, the interaction between acoustic field and curved flame was investigated. As a result of the investigation, non-dimensional number, Pulsating Froude Number, Gp, was newly defined in the present work and it was concluded that the criterion of self-turbulization in acoustic field could be given by the non-dimensional number.