FLUID MECHANICS ANALYSIS OF A SAILBOAT MAST

This study aims to analyze different configurations of mast-sail coupling of a boat with single sail and wishbone rig to vary the shape of the cross-section of the mast that is to assess the influence of the mast on the performance of the sail. The analysis is performed with four several shapes of the mast cross section and several angles of attack to the wind. The numerical simulations on different geometries show an improvement by using a wing shape for the mast rotated in the direction of the wind, in all the corners. This solution allows to rotate rigidly the system mast-boom-sail in order to maintain the same angle of incidence and maximize the efficiency of the sail. The efficiency increase arrives to 73% compared to fixed wing contour profile that is the less efficient for every corner of the wind. The differences among the circular, elliptical and fixed wing contours are not particularly large, but the advantage of rotating wing profile, compared to all the others, is extremely high. Numerical values of lift and drag are congruent with the calculated values. The results of 3D numerical analysis on the rotating wing contour confirm the results of two-dimensional analysis.