Prediction of roll hydrodynamic characteristics for a ship hull section with a high-order finite volume solver

Abstract

This work predicts hydrodynamic characteristics for a rolling ship hull section. Flows about the mid-section of a KVLCC2 under harmonic excited roll motions are simulated with solutions of Navier-Stokes (NS) equations filtered by a large eddy simulation (LES) with a finite volume (FV) solver. This solver applies a fourth-order compact scheme to discrete spatial terms, a fourth-order Runge-Kutta scheme to advance equations, a momentum interpolation method (MIM) to avoid pressure and velocity decoupling, a volume of fluid (VOF) method to capture free surface, and a ghost cell immersed boundary method (GCIBM) to simulate rolling ship. Firstly, verification is implemented to confirm the convergency. Validation is followed by comparison with experimental data. Then, systematic assessments are made on the effects of roll amplitude, frequency and bilge keels by analyzing the tendency of roll moment, damping and added mass moment of inertia as well as flow structures. Wave radiation and viscous effects are elucidated through flow structures. As a result, viscous effect is dominant. Roll amplitude, frequency and bilge keels influence roll hydrodynamic characteristics substantially. Besides, causes of vortex generation, shedding and movement, variation of dynamic pressure field and mechanism of bilge keel to mitigate roll motion are disclosed.