A CFD-based wing sail optimisation method coupled to a VPP

An aerodynamic numerical optimisation procedure for an AC72 rigid wing sail was developed. The core of the methods is the geometric parameterisation strategy based on mesh morphing technique. The morphing action, which uses radial basis functions, is integrated within the Reynolds-averaged Navier-Stokes solver and provides an efficient parametric sail aerodynamic analysis method which is integrated in an optimisation environment based on a velocity prediction program. A hydrodynamic model is coupled to the parametric numerical solver in an iterative procedure. The shape modifiers operate on angle of attack and twist of the fore and aft wing element. For each true wind conditions, the velocity of the boat is maximised iterating between the solution of the velocity prediction program and the solution of the fluid dynamic solver. The effectiveness of the proposed method is demonstrated testing a range of wind speeds and different possible wing planforms.