Numerical study on viscous flow field of forced rolling of ships with bilge keels

Abstract

Rolling is a dangerous motion for navigation, and has been one of the focuses in the investigation of ship hydrodynamics. Large eddy simulation is adopted for the numerical simulation of the viscous flow field around the cross section of Series-60 in the condition of forced rolling. A numerical simulation scheme of high precision is established based on the systematic analysis of spatial and temporal discretization. The integral process of the vortex from generation to dissipation is analyzed in detail by the scheme established, it is demonstrated that a vortex falling off from the bilge keel is not separated but connected to the bilge keel until a reverse motion arise. The influence of roll amplitude and period on the vortex structure is investigated, and it is found that the vortex structure is susceptible to roll amplitude rather than period.