Numerical simulation of a liquid drop freely oscillating

Free oscillations of a viscous liquid drop surrounded by a dynamically inac tive ambient gas, in zero gravity, are investigated numerically using FIDAP (TM) package in the axisymmetrical case. The full Navier-Stokes equations with appropriate interfacial conditions are solved by using Galerkin/Finite element technique along with the spine method for the advection of the fre e boundary are used. The aim of this preliminary study is to demonstrate th e ability of the package to accurately solve nonlinear free surface problem s. Oscillations of viscous drops released from an initial static deformatio n of small to large-amplitude proportional to the second spherical harmonic , without initial internal circulation, are considered. Accuracy is atteste d by demonstrating that (i) the drop volume remains constant, (ii) dynamic response to small and moderate amplitudes agrees well with linear and weakl y non-linear perturbation theories, (iii) large amplitude oscillations comp are well with some numerical and experimental published results.