The first dataset (“Geometries”) contains the three different twist geometries in igs format tested in this experiment. Low, medium and high twist geometries, where the high twist geometry is the reference sail tested in OE, Arredondo-Galeana and Viola, 2018. In the following definitions, the rotational angle "eta_max" is defined as the angle where the spinnaker provided the maximum driving force, considering an optimum apparent wind angle of 55 deg.
The second dataset (“Near Wake”) presents five flow fields. They correspond to the near wake of the high twist spinnaker at 5 PIV measurement planes. They are labelled planes A, B, C, D and E and are located at 7/8th, 5/6 th, 3/4 th, 1/2 th and 1/4 th the distance from the bottom of the sail to the tip. A total of 500 images are averaged per plane. The data was taken for two rotational angles, eta_max that corresponds to the angle where the maximum driving force was measured; and eta_low, which is a lower angle that could be optimum in strong wind conditions, where the lateral force needs to be smaller. Hence two files are found in each subfolder. Every file contains the following channels: ufile, vfile, xfile, yfile where the first two channels are the streamwise and normal velocity components, and the latter two are the cartesian coordinates. Each channel is an array of 16641 x 500 elements, which can be formatted into matrix form as 129 x 129 x 500 elements.
The third data set (“NearWake_TopPlanes”) presents the zoomed in view of the near wake of planes A, B and C, for the three geometries (High twist HT, Medium Twist MT, Low Twist LT) at eta_max. Each file contains the channels: ufile, vfile, xfile, yfile. Each channel is an array of 66049 x 500 elements, which can be formatted into matrix form as 257 x 257 x 500 elements.