Capillary rise between cylinders

The capillary rise of liquid in the gap between two closely spaced parallel cylinders, whose radii are different, was modeled in this paper. On the basis of the minimum free energy principle and interfacial analysis, the vertical capillary rise of liquid at equilibrium was calculated as a function of distance of separation of the two cylinders. In order to validate our theoretical calculation, a piece of experimental apparatus was designed and a series of experiments was conducted on it. Compared to the experimental data, our theoretical model gave a reasonably accurate prediction within experimental error. Copyright (C) 2008 John Wiley & Sons, Ltd.