NUMERICAL INVESTIGATION OF THE DYNAMIC INFLUENCE OF THE CONTACT LINE REGION ON THE MACROSCOPIC MENISCUS SHAPE

The influence of different boundary conditions applied in the contact line region on the outer meniscus shape is analysed by means of a fini te-element numerical simulation of the steady movement of a liquid-gas meniscus in a capillary tube. The free-surface steady shape is obtain ed by solving the unsteady creeping-flow approximation of the Navier-S tokes equations starting from some initial shape. Comparisons of the o uter solutions obtained using two different inner models, together wit h that published by Lowndes (1980), indicate the relative insensitivit y of the outer solution to the type of model utilized in the contact l ine region.