楔形障碍物与火焰的作用

采用多镜头Cranz ＆ Schardin高速摄影机,对卧式燃烧方管内楔形障碍物与CH4/空气预混火焰的相互作用进行了实验研究,获得了高清淅度的障碍物诱导火焰失稳的分幅时序照片.基于RANS方法,对上述复杂物理现象进行了数值模拟.计算结果与实验结果基本相符,反映了火焰在管内传播与变形的详细过程,得到了楔形障碍物所导致的火焰加速与变形的内在机理,揭示了火焰传播过程中由层流燃烧向湍流燃烧转捩的本质.

Interaction Between the Wedge Obstacle and Flame

Experimental investigations have been performed in a horizontal rectangle tube on the interactions between a wedge obstacle and premixed flame of CH4/Air mixture using the Cranz & Schardin high speed camera system.Sequences of high-speed images with high resolution showing the process of a flame instability under the action of the wedge obstacle have been obtained.Besides,based on RANS method,a numerical calculation has been carried for simulating the above complex physical phenomenon.Both experimental and numerical results are in good agreement.These results show the inherent mechanism of flame acceleration and its front distortion,as well as the nature of a transition from laminar combustion to turbulence during its propagation.