Prediction of High Reynolds Number Flow around Naval Vessels

This paper presents in multinational collaborative effort to develop numerical tools and acquire an experimental data base to enable the capability of predicting the flow around naval vessels (surface ship and submarines) at full scale. This effort concentrated on modelling complex geometries (appendages, shaft, struts...) and the mean action of the propeller. A large experimental data base with uncertainty estimates was obtained in a large tunnel facility with a significant difference in Reynolds number, in the towing tank and at full scale on mainly 3 hull forms. CFD development on two codes, one commercially available, the other in house, has concentrated on turbulence model evaluation and selection, as well as numerical uncertainty analysis. The validation effort based on the comparison of computed and measured velocity maps in the same conditions concludes that CFD is capable of modelling the flows considered with reasonable accuracy in the most complex case and with good accuracy for the bare hull case. Comparison with full scale data where free surface effects are present shows that CFD is able to capture the main flow features although more important differences appear. Further work needs to be performed in CFD development and analysis of the data base to make full ause of this data.