Liquid bridge between two moving spheres: An experimental study of viscosity effects

The effects of viscosity on the mechanical response of a liquid bridge are investigated in the case of small amounts of liquid axially strained betwee n two moving spheres. An experimental setup allows the measurement of capil lary and viscous forces exerted on the spheres as a function of the spheres separation distance and the spheres velocity. The experimental results are found to be accurately described over a large range in spheres velocity an d liquid viscosity by a simple closed-form expression. In addition, the bri dge rupture distance is found to increase like the square root of the separ ation velocity. (C) 2000 Academic Press.