Experimental study on the effect of multiple droplet frequency and Weber number to spreading ratio of multiple droplets on a horizontal surface

摘要

In this study, the phenomena of multiple droplet impingements are investigated and observed experimentally. A high-speed camera was used to capture sequential images of multiple droplet impingements. Image processing technique was used to analyze the images from a high-speed camera. The effect of droplet frequency and Weber number to spreading ratio are investigated. The result of this study shows that frequency of multiple droplets has no significant effect to spreading ratio in the first drop. It is found that frequency of the multiple droplets causes a wider spreading ratio in the second drop. On a lower Weber number and lower surface temperature, the spreading ratio is smaller than on a higher weber number. It is also found that surface temperature has a strong correlation with the spreading ratio. It was also found that at a higher surface temperature, the spreading ratio of a droplet is relatively unstable in the function of time.