Experimental Full Scale Study on Yacht Sails and Rig under Unsteady Sailing Conditions and Comparison to Fluid Structure Interaction Unsteady Models Available to Purchase

This work presents an experimental study on the aeroelastic wind/sails/rig interaction at full scale in real navigation conditions with the aim to give an experimental validation of unsteady Fluid Structure Interaction (FSI) models applied to yacht sails. An onboard instrumentation system has been developed on a J80 yacht to measure simultaneously and dynamically the navigation parameters, yacht motion, and sails flying shape and loads in the standing and running rigging. The first results recorded while sailing upwind in head waves are shown. Variations of the measured parameters are characterized and related to the yacht motion (trim mainly). Coherence between the different parameters is examined. In the system’s response to the dynamic forcing (pitching motion), we try to distinguish between the aerodynamic effect of varying apparent wind induced by the motion and the structural effect of varying stresses and strains due to the motion and inertia. The simulation results from the FSI model compare very well with the experimental data for steady sailing conditions. For the unsteady conditions obtained in head waves, the first results show a good agreement between measurements and simulation.