Coalescence of Two Drops on Partially Wettable Substrates

Abstract

The present work contains the results of the experiments with two tiny drops on partially wettable substrates with contact angles of 10 degrees, 24 degrees, 27 degrees, and 56 degrees, which coalesce in the regime entirely dominated by viscous forces. Both side and bottom views are examined. The results for these three-dimensional coalescence flows are compared with scaling laws and the numerical two-dimensional model developed in the present work.