Maximum Spreading for Liquid Drop Impacting on Solid Surface

This paper investigates maximum spreading associated with liquid drop impact on a solid surface. By use of highspeed video, the transient spreading with fluids of water, butanol, and ethanol is observed and analyzed to further clarify the assumptions made in many modeling studies. Fluid properties have considerable effects on spreading, in which viscosity is relegated to a secondary role compared to surface tension in the spreading magnitude. Several commonly used predicting methods for the maximum spreading factor are assessed based on a consolidated database consisting of 213 data points amassed from 11 sources. A practical formula with quite good precision for predicting the maximum spreading scale of the fluids with low viscosity of mu(f) < 0.01 Pa.s is obtained. A new formula for dimensionless time related to maximum spreading is also provided based on the measured data of fluids with high surface tension.