Flow survey around bilge keel during roll motion

The results of an experimental analysis of the velocity field around a ship model in forced roll motion are presented. Tests, carried out at the INSEAN towing tank n° 2, aim to achieve a better physical understanding of the fluid dynamic aspects involved and a certified experimental data set for CFD validation. Results describe the evolution of the flow field in two cross sections along the bilge keels during the first cycle of the damped time history. The effectiveness of the bilge keels is discussed, highlighting diffusion and interaction of the vorticity with the boundary layer.