A CFD model for the frictional resistance prediction of antifouling coatings

The fuel consumption of a ship is strongly influenced by her frictional resistance, which is directly affected by the roughness of the hull׳s surface. Increased hull roughness leads to increased frictional resistance, causing higher fuel consumption and CO2 emissions. It would therefore be very beneficial to be able to accurately predict the effects of roughness on resistance. This paper proposes a Computational Fluid Dynamics (CFD) model which enables the prediction of the effect of antifouling coatings on frictional resistance. It also outlines details of CFD simulations of resistance tests on coated plates in a towing tank. Initially, roughness functions and roughness Reynolds numbers for several antifouling coatings were evaluated using an indirect method. Following this, the most suitable roughness function model for the coatings was employed in the wall-function of the CFD software. CFD simulations of towing tests were then performed and the results were validated against the experimental data given in the literature. Finally, the effects of antifouling coatings on the frictional resistance of a tanker were predicted using the validated CFD model.