Analysis of the vortex shedding from a rolling ship model in a large facility

The paper describes the results of an experimental analysis of the velocity field around a ship model in forced rolling motion. Tests, carried out at the INSEAN Circulating Water Channel, aim to obtain suitable data for CFD validation. Results describe the evolution of the wake along three cross sections of the wake along the bilge keels and just downstream the rudder,are presented and discussed for the bare hull and fully appended configurations. Flow field is resolved in phase with the roll motion to point out flow structures by using laser Doppler velocimetry. The effectiveness of the bilge keels in damping the roll motion is demonstrated by the generation of strong vortical structures which are dominating in the flow field.