Experimental Examination of Contact Line Dynamics in a Liquid Bridge Scenario

Liquid bridges between particles play an important role in industrial slurries and soils, but their effects are not well understood. We experimentally measure the normal and lateral forces exerted by microliter scale liquid bridges between solid spheres and simultaneously acquire detailed images of the bridge shape. We developed a model for the lateral and normal forces as a function of displacement by analyzing the bridge shape; this analysis incorporates hysteresis and elucidates the fundamental basis for the nonequilibrium contact line force in terms of the properties of the surface and their influence on the liquid-air interface.