Investigation On The Aerodynamic Performance Of A Sail Wing Of Windsurfing With Different Angles Of Attack

The sail wing is the power source of windsurfing,and its aerodynamic performance affects the speed of windsurfing.With the change of angles of attack,the aerodynamic performance of windsurfing will change,resulting in the deformation of the sail wing.Therefore,in this study based on the CFD and CSD numerical method,using the ALE coordinate system and the RANSE to study Neil Pryde RS:X sail wing's aerodynamic performance and the deformation under fluid--structure interaction.One-way fluid-structure interaction transfers the steady-state flow field data of the rigid sail wing to Static Structure as load,calculates the deformation and stress of the sail wing.Through System Coupling two-way fluid-structure interaction exchange data in each time step.One-way fluid-structure interaction calculation shows that the stall angle is between 25 and 30 degrees,and in 30 degrees regular vortices are generated on the leeward side of the sail wing.In the two-way fluid-structure interaction calculation,the stall angle of the sail wing is about 30 degrees,and in 35 degrees the regular vortices begin to appear.Therefore,the effective angle of attack of the sail wing decreases when two-way fluid-structure interaction is considered.The velocity distributions of the sail wing at Z=1.45 m cross section are basically the same.The velocity at the mast on the windward side is greater than that at the inflow side,and the velocity at the rear side is the smallest.The velocity at the wake behind the sail is the largest and the speed at the camber of the sail wing is the smallest.In the structural field,the maximum deformations of the sail wing calculated by two methods are different.In the one-way fluid-structure interaction,the maximum deformations of the sail wing appeared at the top corner of the sail,while in the two-way fluid-structure interaction,the maximum deformations of the sail wing appeared in the middle of the rear.From the maximum deformation curve,due to the feedback effect of vortex-induced vibration,the maximum deformation of sail wing calculated by one-way fluid-structure interaction is larger than that in two-way fluid-structure interaction.In order to make the numerical simulation more practical,the two-way fluid-structure interaction method should be used to study the sail wing's aerodynamic performance.Through numerical simulation,the aerodynamic performance of the sail wing considering fluid-structure interaction at different angles of attack is obtained,which can help coaches and athletes understand the aerodynamic performance of the sail wing,and help the athletes control the sail wing more reasonably in the competitions,so as to achieve better results,and provide some theoretical support for the scientific training of sailing.