To investigate the effect of the flame inherent instabilities and turbulence on the flame structural characteristics, premixed combustion experiments of 50% H₂/50% CO at a equivalence ratio of 0.6 were conducted in a turbulent combustion bomb in atmospheric temperature and pressure. The correlation degree was defined to study the correlation relation between flame structural characteristics at different moments, and the wavelet transform was used to investigate the detail components at different scales. The results indicate that, with the development of the flame, the cellular structure was enhanced and the correlation degree gradually decreased. The fluctuations of the detail components at the larger scale were stronger and included more energy, which corresponded to the main factor causing the flame front complex. With the turbulence intensity increase, the root mean square amplitude and energy of the detail components increased, leading to the increase of the interaction of different disturbances, while the correlation degree of the flame decreased. The correlation degree of the detail components presented a staggered distribution of higher and lower values, which indicated the complex changes of the disturbances at different scales.

中文翻译：

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基于小波变换的湍流预混火焰结构特性试验研究

为了研究火焰固有的不稳定性和湍流对火焰结构特性的影响，采用50％H _2的预混燃烧实验在大气温度和压力下，在湍流的燃烧弹中以当量比为0.6的比例/ 50％的CO进行测试。定义相关度以研究不同时刻火焰结构特征之间的相关关系，并利用小波变换研究不同尺度下的细节成分。结果表明，随着火焰的发展，细胞结构增强，相关度逐渐降低。较大范围的细节分量的波动更强，并且包含更多的能量，这与导致火焰前部复杂的主要因素相对应。随着湍流强度的增加，细节成分的均方根振幅和能量增加，导致不同扰动的相互作用增加，而火焰的相关度降低。细节分量的相关程度呈现出较高和较低值的交错分布，这表明不同尺度下干扰的复杂变化。