Existence theorems and measurement of the capillary contact angle (Q686392)

Summary: In an earlier work \textit{P. Concus} and \textit{R. Finn} [to appear in Proc. IUTAM Symp. Micrograv. Fluid Mech., Bremen 1991] proposed two procedures, based on a dichotomous behavior of fluid in capillary tubes at zero gravity, designed for accurate measurement of capillary contact angles. The present work offers modifications to one of their procedures which should facilitate the experiments and lead to improved accuracy. The discussion leads to explicit characterization of a capillary tube with ``canonical'' section, which has an independent mathematical interest.