Planar laser-induced fluorescence (PLIF) techniques have been widely used for flame structure visualization in recent years. Nevertheless, most of the studies were concerned with qualitative analysis of the obtained images and the quantitative analysis were much fewer. This work presents a quantitative feature extraction method to process the ribbon structures that are captured in images and represent the radical layers in flames. The extracted features include ridge lines, curvatures, and thicknesses. This method was demonstrated by processing the images of methyl (CH3) photofragmentation laser-induced fluorescence (PF-LIF) and formaldehyde (CH2O) PLIF measurements in stoichiometric, premixed methane/air flames. The flames were generated by a McKenna burner under the Reynolds numbers of 1930, 3870, and 5800. The ridge lines followed well with the wrinkled layers of CH3 and CH2O. The CH2O layers were thickened, but the CH3 layers had minor change with increased Reynold numbers.

中文翻译：

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光碎裂激光诱导的荧光定量提取湍流预混火焰

近年来，平面激光诱导荧光（PLIF）技术已广泛用于火焰结构的可视化。然而，大多数研究都与获得的图像的定性分析有关，而定量分析却少得多。这项工作提出了一种定量特征提取方法，以处理图像中捕获的并代表火焰中的自由基层的带状结构。提取的特征包括山脊线，曲率和厚度。通过在化学计量的甲烷/空气混合火焰中处理甲基（CH3）光碎裂激光诱导的荧光（PF-LIF）和甲醛（CH2O）PLIF测量图像，证明了该方法。火焰是由McKenna燃烧器产生的，雷诺数分别为1930、3870和5800。脊线与CH3和CH2O的褶皱层相吻合。CH2O层变厚，但是随着雷诺数的增加，CH3层的变化很小。