The use of detached eddy simulation in ship hydrodynamics

Description/Abstract

Accurate numerical simulation of the flow around the hull of a ship remains a challenging task. This work examines whether this is as a result of the inherent unsteady burbulent flow regime influencing the position and strength of vortex systems shed in the weake. TO this end the behaviour of the flow around a truncated cylinder is taken as an exemplar of flow at the stern of a ship. Wind tunnel tests of the flow around a KVLCC2 hull form were made to meausre the flow field at the propeller plane using particle image velocimetry. Comparison of the instantaneous and the mean flow field indicate significant low frequency effects with large deviations form the mean flow. Such behaviour is also found in the wake of an aspect ratio 1 truncated cylinder. The approach at capturing the on and off body flow field is compared with detaile experiments and previous calculations of a Reynolds Averaged Navier Stokes with k-e model and Large Eddy Simulation (LES). THe results clearly show significant improvements witht the use of DES. Further work is on-going to apply the DES approach to a full ship simulation.