  The article demonstrates that the internal circulation velocity and patterns
in sessile droplets on superhydrophobic surfaces is governed by the surface
curvature. Particle Image Velocimetry reveals that increasing convexity
deteriorates the advection velocity whereas concavity augments it. A scaling
model based on the effective curvature modulated change in wettability can
predict the phenomenon, but weakly. Potential flow theory is appealed to and
the curvatures are approximated as wedges with the rested droplet engulfing
them partly. The spatially averaged experimental velocities are found to
conform to predictions. The study may have strong implications in
thermofluidics transport phenomena at the microscale.
