Hydrodynamic ship-ship and ship-bank interaction: A comparative numerical study

The hydrodynamic interaction between ships or between the ship and the bank was studied by numerical methods. A number of new numerical results were obtained, for both ship-ship interaction and ship-bank interaction cases, by applying the double-body potential flow code HYDINTER earlier developed at Instituto Superior Tecnico (University of Lisbon, Portugal). A comparative numerical study was made between these results and those obtained earlier for the same ship forms at Ghent University (Belgium) with a different potential code (ROPES), with a Computational Fluid Dynamics (CFD) code (ISIS-CFD) and with Experimental Fluid Dynamics (EFD) data obtained in the shallow water towing tank at Flanders Hydraulics Research, Belgium. A panel method is - in comparison with CFD - relatively fast and can often be used in real-time simulations. Because of this substantial benefit, the research focuses on identifying the limitations of applicability of this alternative computation method which neglects viscous effects and free-surface deformation. In this research, on the one hand good predictions are obtained for ship-ship interaction between encountering ships. On the other hand, the results for ship-bank interactions fail to predict the experimental trends. The errors increase at very close distances to the bank or another ship. The same holds true for the cases characterised by very large drift angles e.g. a tug crabbing near a large vessel.

Automated summary

The study investigates hydrodynamic interactions between ships or between ships and banks using numerical methods. Results from different computational methods show good predictions for ship-ship interactions but fail to accurately predict ship-bank interactions. Errors increase at close distances to the bank or another ship, particularly in cases with large drift angles.