Experiments were conducted to explore the droplet generation process when an ascending liquid spray impacts on a downward-facing solid surface. The droplets generated in the present experiments were classified into the two types: one is the splashing droplets generated by the impacts of droplets in spray and the other is the falling droplets produced from a liquid film formed on the solid surface. The falling droplets were further classified to the first falling droplets and the satellite droplets. It was found that the ratio of the splashing droplets increases with an increase in the impact Weber number. As for the droplet size, the splashing droplets were much smaller than the falling droplets. Hence, the oil immersion method and the image analysis were used to measure the sizes of the splashing droplets and the falling droplets, respectively. The size of the splashing droplets was in the same order with the impacting droplets in spray. On the other hand, the size of the falling droplets was proportional to the wavelength of the most unstable wave in the Rayleigh-Taylor instability. Interestingly, the diameters of the falling droplets (first falling and satellite droplets) were inversely proportional to their order. Using the experimental data accumulated in this work, dimensionless correlations were developed for the rates and sizes of the splashing and falling droplets.

进行实验以探索当上升的液体喷雾撞击朝下的固体表面时的液滴产生过程。在本实验中产生的液滴被分类为两种类型：一种是由喷雾中的液滴的冲击产生的飞溅的液滴，另一种是由在固体表面上形成的液膜产生的下落的液滴。将下落的液滴进一步分类为第一下落的液滴和附属液滴。发现飞溅的液滴的比率随着冲击韦伯数的增加而增加。至于液滴尺寸，飞溅的液滴比下落的液滴小得多。因此，油浸法和图像分析分别用于测量飞溅的液滴和下落的液滴的尺寸。飞溅的液滴的大小与喷雾中的冲击液滴的顺序相同。另一方面，下降的液滴的大小与瑞利-泰勒不稳定性中最不稳定的波的波长成正比。有趣的是，下降的液滴（第一次下降和附属液滴）的直径与它们的顺序成反比。使用在这项工作中积累的实验数据，开发了无量纲的相关性，用于飞溅和下落的液滴的速率和大小。下降的液滴（第一次下降和附属液滴）的直径与它们的顺序成反比。利用在这项工作中积累的实验数据，开发了无量纲的相关性，用于飞溅和下落的液滴的速率和大小。下降的液滴（第一次下降和附属液滴）的直径与它们的顺序成反比。利用在这项工作中积累的实验数据，开发了无量纲的相关性，用于飞溅和下落的液滴的速率和大小。