Abstract
To study the generation and development of bilge vortices around the stern of full ship form, flow observations were carried out for small ship models in a water channel using dye tracer.
With a simplified wall-sided hull form, the shape of bottom flat and bilge radius were varied. A conventional hull form was also tested.
As a result, it was found that the size of bilge vortices were affected significantly by the shape of bottom flat of stern, i.e. bottom flat with smaller shoulder angle produces vortices of smaller radius and blunter one produces larger vortices. For conventional full ship forms, the bilge vortices became visible approximately at the square station 1 (10% ship length from stern). Further it was found that the core of bilge vortices moved toward the water surface with the increase of radius of bilge circle.
