Final project of the course

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Mast and Sail Aerodynamics Final Report for the project of the Computational Fluid Dynamics course Group number 14 Niccolò Berizzi, 10685173 Riccardo Bertoncello, 10676871 Y ashil Choony , 10610071 Alessandro Crotta, 10621786 Matteo Dall’Ora, 10687723 Lecturer: Prof. Alberto Guardone Tutor: Francesco Caccia 1. Problem statement 1.1. Abstract The aerodynamic behaviour of the sail and its interaction with the mast are crucial aspects in the determination of the overall performance of a sailing boat. The sail is responsible for the creation of the driving force, also calledthrust, sustaining the boat motion; the mast, placed ahead of the sail, transmits instead the aerodynamic loads to the boat’s hull. The goal of this study is to perform aCFD analysis of a two-dimensional section of a thin sail, connected to its circular, non-rotating mast, under specific wind conditions at different angles of attack. In particular, the flow field and the aerodynamic coefficients obtained considering amast-sail configuration and asail configuration are compared. Precise emphasis was also placed on the separation bubbles behind the mast, the peculiarCP distribution on the body, and the possible unsteadiness of the wake at high angles of attack. The study has been carried out exploiting the open source CFD software SU2. Results were validated using a wind tunnel experiment available in literature, carried out by Stuart Wilkinson in 1984, Ref.[1], and the numerical simulations from Jonathan Paton’s PhD thesis, performed on the CFD software ANSYS FLUENT on the same geometry in 2011, Ref.[2]. 1.2. Introduction Sailboats are able to exploit the relative wind speed to create a pushing force, which allows the boat to move over the sea surface. Thanks to their versatility in terms of both shape…