Liquid sheet behaviors during a drop impact on wetted cylindrical surfaces

Experimental observations and measurements concerning liquid sheet characteristics after a single butanol drop impact on wetted cylindrical surfaces are performed using a high speed digital camera at 10,000 frames per second. The cylinder-drop curvature ratio ranges from 0.091 to 1.152. It is observed that the curvature ratio can affect the liquid sheet shapes a lot. With the curvature ratio decrease, the liquid sheet approximates to the typical crown gradually. Quantitative analyses about the liquid sheet height, width and the specific time that the height achieves the peak value are discussed. The results reveal that the liquid sheet height and its corresponding time can be increased by increasing the impact Weber number or by reducing the curvature ratio. The Weber number has a weak effect on the sheet width in the generatrix direction, while it can greatly influence the width in the directrix direction. Additionally, the curvature ratio almost has no influences on the sheet width, and a well-fit correlation for the width in the generatrix direction is obtained successfully when the curvature ratio is less than 0.5. Finally, the liquid sheet angle is investigated. It is found that with the decrease in the curvature ratio, the angle grows obviously. (C) 2014 Elsevier Ltd. All rights reserved.