Performance optimization of interacting sails through fluid structure coupling.

Abstract

In this paper, the problem of sailing yacht rig design has been addressed through the development of a computational framework based on viscous Computational Fluid Dynamic (CFD) modelling for the aerodynamic part and on a non linear structural modelling for the structure part. The Fluid Structure Interaction (FSI) coupling used is a loose coupling. The interest but also the expertise needed to use Reynolds Averaged Navier-Stokes (RANS) equations for the aerodynamic modelling is justified through examples and validations with a focus on complex separated flow configurations. The originality of the presented computational framework is its ability to address complex, non linear optimization problems with a derivative free evolutionary strategy. This capability is enhanced by the fact that it is based on a remeshing technique rather than on a deforming mesh one. After the description of the main elements of this computational framework for Fluid Structure Interaction, it is used for generic sail optimization problems and for the rig design of a 18 footer to illustrates its capabilities and limitations to produce accurate aeroelastic solutions on sailing yacht rigs.