Sessile drop sloshiness on vibrating films

Droplet-cantilever interactions dominate various engineering phenomena like energy harvesting via raindrops, flight of micro-flyers, bloodsplatter analysis, pesticide retention, and vibration damping. Traditional research on drop-cantilever interactions have focused on one dimensional motion from liquid impact, vibration or ejection. In this study, we address a gap in traditional drop-cantilever research by looking into a continually forced, flexible, hydrophilic cantilever beam that deforms water droplets on its fixed and free ends. Using an electrodynamic shaker, we vibrate cantilevered elastomers of varying stiffness vertically across a range of shaker amplitude and frequency. We quantify the dissipation of kinetic energy imparted by the cantilever beam to the sloshing droplets. By comparing the drop shapes atop fixed cantilever end to those positioned at the cantilever tip, we quantify the influence of substrate compliance on drop 'sloshiness'. At fixed frequencies, drops on the free end slosh more with increasing vibration amplitude. Droplets slosh more unpredictably at higher substrate accelerations.