Elliptical footprint drop impact on a solid surface: the role of the impact angle

Control of drop impact dynamics on solid surfaces has gained a significant attention in a wide range of practical applications, such as surface coating and cooling. Classical drop dynamics is assumed to be axisymmetrical, so symmetry breaking in the dynamics can result in the modified drop hydrodynamics. Drop shaping with an elliptical footprint at the impact moment could alter impact dynamics significantly, leading to anti-rebound by inducing the extraordinary spreading and retraction dynamics, which was previously studied. Here, we focus on the effect of the impact angle on the dynamics during the elliptical drop impact on nonwetting surfaces. The impact angle plays a crucial role in modifying impact dynamics and suppressing bounce magnitude, which are investigated experimentally and numerically. We determine the rebound/deposition regime for varying impact angles, aspect ratios of the shapes, and Weber numbers. The quantitative analyses of the axial momentum of the horizontal and vertical axes are conducted to interpret the mechanism behind the drop deposition at low impact angles.