Direct femtosecond shadowgraphy and supercontinuum (SC)-illumination imaging methods for diagnosing liquid-gas mixed sprays in the near-field region of spray nozzles were compared. Some big spray structures can be captured using femtosecond shadowgraphy which can freeze the motion of the sprays. But the speckles caused by the interference of multi-scattered photons erode the edges of ligaments and conceal many fine droplets. SC-illumination imaging can not only freeze the motion of the sprays but also significantly suppressing the speckles, presenting a more realistic spray pattern. Based on the SC imaging technology, the effects of various factors such as flow ratio of gas to liquid (GLR), total flow and nozzle size on the spray were studied.

中文翻译：

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飞秒激光诱导的超连续谱成像方法在近场区域的气液混合喷雾诊断。

比较了飞秒直接影影法和超连续谱（SC）照明成像方法在喷嘴近场区域中的液-气混合喷雾诊断方法。飞秒阴影可以捕获一些大型喷雾结构，从而冻结喷雾运动。但是，由于多散射光子的干扰而引起的斑点会侵蚀韧带的边缘并掩盖许多细小的液滴。SC照明成像不仅可以冻结喷雾的运动，而且可以显着抑制斑点，从而提供更逼真的喷雾模式。基于SC成像技术，研究了气液比（GLR），总流量和喷嘴尺寸等各种因素对喷雾的影响。