Droplet impact on rotating surfaces: The effect of centrifugal force and wettability on spreading dynamics

Droplet impacting on rotating surface experiences the tangential shear force from the rotating surface, generating a centrifugal force that either enhances the spreading or destabilizes the expanding lamella. In this study, we experimentally characterize the impacting of droplets with a wide range of viscosity on rotating surfaces with various wettabilities, and theoretically analyze the observed impacting dynamics, including the enhanced spreading and the transition to the destabilization of the expanding lamella. We propose a simplified approach to predict these key parameters, and validate the theoretical prediction by experimental measurement.