Deformation characteristics and energy conversion during droplet impact on a water surface

Abstract

The present work studies experimentally and numerically the impact of water droplets with different Weber numbers (We) on a water surface. Correlations between Weber number and geometric sizes of central jet, secondary droplet, and secondary central jet are analyzed using linear regression. The experimental and numerical results are compared qualitatively and quantitatively and show good agreement. In addition, the energy conversion during the impact process is calculated using a numerical integration method. It is concluded that the ratio of the secondary droplet to the initial droplet diameters is approximately within 1.2-2, and this diameter ratio correlates linearly with the Weber number within the experimental ranges tested. When 360 < We < 713, the secondary central jet is generated. Moreover, the target liquid adsorbs around 70% of the initial total energy. The total energy remains around 64% when the cavity reaches its maximum depth, whereas it remains around 39% when the kinetic energy of the central jet reaches its minimum.