We photographed the impact of molten droplets on a flat plate. From these images we measured droplet dimensions during spreading and counted the number of fingers around a splashing drop. Experiments were done using stainless tell substrates with average roughness of 0.06, 0.07, 0.56, and 3.45 μm respectively. The temperature of the substrate was kept at either 25 or 240°C. Droplet diameter(2.2 mm) and impact velocity(4 m/s) were kept constant, giving a Reynolds number (Re) of 31 135 and Weber number (We) of 463. Raising substrate roughness from 0.06 to 0.56 μm enhanced the tendency of droplet to splash, whereas increasing Roughness even further to 3.45 μm suppressed splashing.
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机译：我们拍摄了熔融液滴对平板的影响。从这些图像中，我们测量了散布过程中液滴的尺寸，并计算了飞溅液滴周围的手指数量。使用平均粗糙度分别为0.06、0.07、0.56和3.45μm的不锈基材进行实验。基板的温度保持在25或240℃。液滴直径（2.2 mm）和冲击速度（4 m / s）保持恒定，雷诺数（Re）为31 135，韦伯值（We）为463。将基材粗糙度从0.06提高到0.56μm可以增强涂层的趋势。液滴飞溅，而将粗糙度进一步提高到3.45μm可抑制飞溅。
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