A Numerical Model for Three Dimensional Polydisperse Bubbly Flows around Surface Ships

A model for simulating three dimensional polydisperse two-fluid open bubbly flows is presented. The polydisperse model is based on an integro-differential equation for the bubble size distribution function. A multigroup approach is used to discretize the equations in groups of constant mass. The resulting system has four scalar equations (mass and momentum) for the liquid phase and for each group on the gas phase. The model has been implemented in the code CFDSHIPM. Although it is intended mainly for solving surface ship problems, it is flexible enough to simulate many other bubbly flow problems. Some preliminary results for two problems are presented here: 1) a turbulent boundary layer over a flat plate with injection of bubbles of 4 different sizes, and 2) a surface ship with simulated breaking waves boundary conditions. Void fraction and number density solutions are shown and analyzed. A. Larreteguy, D. Drew, P. Carrica, F. Bonetto. 2