The hydrodynamic flow around a yacht keel based on LES and DES

The work presented in this paper focuses on the CFD application of large eddy simulation (LES) and detached eddy simulation (DES) to the prediction of the forces acting on an International America's Cup Class yacht keel model exposed to uniform incident flow at turbulent Reynolds number regime. The simulations were performed using both methods on adapted unstructured grids. The model keel used in the current study was developed by Chalmers University for experimental purposes, and is used for validation of CFD codes in yacht hydrodynamics. Initial results obtained are compared and validated against existing experimental data from wind tunnels in terms of lift and drag coefficients measurements and wake flow observations behind the keel. Two sub-grid scale models for LES and two turbulence models for DES are investigated and compared. Sensitivity to numerical parameters is also addressed. Overall, qualitative results and predictions are satisfactory and quantitative findings agree and fit well with the experimental values although error in forces prediction is high in some cases. (C) 2012 Elsevier Ltd. All rights reserved.