Numerical studies of fluid oscillation problems by boundary integral techniques

A numerical technique has been developed to investigate the axisymmetric large amplitude oscillations of an inviscid and incompressible liquid drop about its spherical equilibrium shape. The drop is placed into a microgravity environment. Thus the only forces acting on the drop are surface tension forces. The internal flow field of the fluid drop is assumed to be irrotational, so that the methods of classical potential theory can be applied. A solution for the Laplace equation for the velocity potential is posed in form of the potential of the simple layer, where the sources are placed on rings (circles) covering the bounding surface of the drop. Discretization of the drop into discs and caps at the poles, application of the dynamic and kinematic boundary condition and numerical integration with respect to time of the latter allows to study the behaviour of the deformed drop and to determine the eigenfrequencies.