Particle modeling of liquid drop formation on a solid surface in 3-D

Using a molecular aggregate approach and classical Newtonian dynamics, we show how to simulate a liquid drop formation on a horizontal solid surface in three-dimensional space. We use sets of quasi-molecular particles which interact in accordance with classical molecular-type formulas. For application, the liquid is taken to be water while the solid surface is taken to be graphite. The resulting dynamical equations for the particles are large systems of second-order, nonlinear, ordinary differential equations which must be solved by a numerical method. Computer simulations of the results and related contact angle calculations are presented and discussed. The results are in complete agreement with experimentation and the method can be extended to nonflat surfaces.