||Augier Benoit1, Paillard Benoît2, Sacher Matthieu3, Leroux Jean-Baptiste3, Aubin Nicolas4
||INNOV`SAIL 2020 - 5th Edition of the International Conference on Innovation in High Performance Sailing. 15 - 17 June 2020, Virtual Conference.
||INNOV'SAIL - Proceedings of the 5th International Conference on Innovation in High Performance Sailing Yachts and Sail-Assisted Ship Propulsion Gothenburg – Sweden (Online) 15th - 17th June 2020. Session 1 Aerodynamics, pp.17-26
The “verge of curling” recommendation is one of the common advice that sailors follow for efficient sailing downwind with a spinnaker. Wind tunnel experiments on spinnaker models conducted by [Aubin et al., 2017] in the Twisted Flow Wind Tunnel of the Yacht Research Unit of the University of Auckland have shown that curling can be related to better performance at Apparent Wind Angle ≥ 100°. In the present article, we will focus on the aerodynamic performance jump observed at Apparent Wind Angle AWA = 100°, where the drive force increases up to 15% when the sail starts to flap. Thanks to four triggered HD cameras and coded targets stuck on the sail, three flying shapes of the spinnaker are reconstructed by photogrammetry for different sheet lengths from over trimmed to flapping occurrence. The pimpleFOAM solver from OpenFOAM is used to simulate the aerodynamic for the three rigid extracted flying shapes. Results highlight the ability of the model to simulate the experimental jump observed closed to curling and the significant confinement effect of the roof of the wind tunnel.
|Publisher's official version