Numerical Simulation of the Flow Around a Ship Hull with Enforced Motion

During last years an increased interest in the study of the hydrodynamics of marine vehicle in unsteady motion has been observed; in fact, due to safety and comfort arguments, the unsteady flow field around ship hull in free or imposed motion is one of the major field of research in the framework of marine hydrodynamics. Analysis by numerical investigation of such kind of problems requires ad hoc methodologiies capable to deal with unsteadiness in non-inertia frame of reference. In this work we present an unsteady version of the well established multiblock code, developed for the numerical simulations of steady free-surface flow around complex geometries such as ship hull. A detailed presentation of the proposed numerical algorithm is given. As validation test cases laminar steady and unsteady flows around fixed and oscillating cylinder of square and circular transverse section have been considered; the unsteady turbulent flow around a ship hull in forced rolling motion has been considered as an application. The the last test case, results obtained using three turbulence models will also be presented.