By its international involvements, such as the ITTC and the NATO Science and Technology meetings, Flanders Hydraulics keeps an active interest in the developments that take place within the Computational Fluid Dynamics (CFD) world. This exciting field of research offers the opportunity to study specific hydrodynamic problems which are difficult or impossible to study by experimental means. In addition, due to the relative short computing times, CFD can be used as a practical and cost-effective alternative for one-off experimental research. With decreasing costs of computing facilities and improvements in numerical algorithms, more complicated configurations can be tackled by CFD.
However , shallow water conditions and confined environments are still a challenge. The interaction with a nearby bottom or wall leads to a highly complex flow, which requires a much finer mesh in certain critical areas and thus longer computing times.
In order to contribute to this area of research, FH uses the CFD software package FINE™/Marine developed by NUMECA. The turbulent air-water flow around a vessel is computed with the Reynolds-Averaged Navier-Stokes equations. Initial research focused on recreating experimental cases that were investigated in the towing tank at Flanders Hydraulics, such as ship-bank interaction and ship-ship interaction. Currently, research focuses on the behaviour in shallow water of ships with a drift angle of 30 degrees. The figure at the right shows the mass fraction on the hull and streamlines to visualize the massive separation region that originates at the bow in this condition.
