A numerical investigation into the heave, sway and roll motions of typical ship like hull sections using RANS numerical methods

[摘要] ENGLISH ABSTRACT: The hydrodynamic characteristics of three typical ship-like hull sections, indifferent motions, are numerically investigated using FLUENT, 2009. Thesesimple shapes, namely a v-bottom (triangle) hull, aat-bottom (square) hulland a round-bottom (semi-circle) hull, are investigated in uncoupled heave,sway and roll. The problem is described in two dimensions. A combination ofnumerical methods and models, found in literature, are used to conduct thisinvestigation. Hull characterisation is achieved through the use of hull massand damping coe cients. These numerically determined coe cients are comparedto experimental work conducted by Vugts (1968). A good correlationbetween the numerical and experimental results exists for the heave and swaycases. By normalising the coe cients, different hulls are comparable to oneanother. The numerical models used are validated and veri ed. Roll motionremains largely unsolved for very large angles of roll (in excess of 11°). Different uidow phenomena occurring around the hull sections have varyingdegrees of in uence on the motions of a hull. It is found that not one of theturbulence models investigated can be employed to globally solve each typeof hull-motion case. Also, forced oscillations in computational simulations requireconsiderably more computational time than free-decay oscillating hullsimulations.

[发布机构] Stellenbosch University