DISPLACEMENT OF PARTICLES DEPOSITED ON SOLID SURFACES BY A MOVING GAS-LIQUID-SOLID INTERFACE

ABSTRACT

Deposited small particles change their position and can build aggregates on surfaces when wetted/dewetted. The size and form of these aggregates depend on the amount of water condensed, the form of the particles and the contact angles. Experiments with glass spheres and quartz particles on three different surfaces with water as wetting liquid were carried out. Results of the wetting/dewetting experiments are shown and discussed. A model is presented to estimate the magnitude of involved forces and the displacement of the particles taking into account contact angles, amount of condensed water, and size of particles. The model explains, why particles, as observed, tend to gather near the edge of a droplet at small surface contact angles and near the droplet center at high surface contact angles.