A parametric study : hull roughness effect on ship frictional resistance

Demirel, Yigit Kemal and Turan, Osman and Incecik, Atilla and Khorasanchi, Mahdi (2013) A parametric study : hull roughness effect on ship frictional resistance. In: Marine Coatings Conference, 2013-04-18.

Full text not available in this repository.

Abstract

Ship resistance is very important in terms of ship performance and fuel consumption. The more resistance a ship has, the more fuel it consumes for the same range. Ship resistance can be broken into two parts; frictional resistance and residuary resistance. Especially for merchant ships which sail with normal or low velocity, frictional resistance may be 60-90% of the total resistance and it is directly affected by surface roughness; namely physical and biological roughness. Hull roughness leads to frictional resistance increase which means fuel penalty. Marine coatings are widely used in order to avoid or minimise fouling and hull roughness, hence increase in frictional resistance. This paper outlines details of a parametric numerical study which was carried out to monitor the effect of changing surface roughness of marine coatings on ship frictional resistance. This investigation was made by means of a computational fluid dynamics (CFD) based software (STAR-CCM+). Firstly, towing test simulations of a flat plate were conducted and the results were compared with the experimental results given in literature to validate the model. After the validation procedure, a parametric study was carried out to obtain frictional resistance and frictional drag coefficient variations depending on various hull roughness conditions. Moreover, a simple formulation which correlates the roughness height and frictional drag coefficient was obtained within the validated roughness height range and speed. Finally, the results were presented in both graphical and tabular forms and discussed in details.