Vortex flows of downwind sails - PIV data

Three different spinnaker twist prototypes were manufactured (“Geometries” dataset) and their near wake was studied with Particle Image Velocimetry (PIV). The reference sail (high twist geometry) was recorded in uniform flow in a water flume (“Near Wake” dataset). This geometry provided the highest maximum driving force, assuming an apparent wind angle of 55 deg. The data set contains 5 particle image velocimetry measurement planes along the span of the sail. The planes are labelled A, B, C, D and E and are located at 7/8th, 5/6th, 3/4th, 1/2th and 1/4th the distance from the bottom of the sail to the tip. A total of 500 images are recorded per plane. The reference geometry can be found in Arredondo-Galeana and Viola, in OE, 2018. The top planes of the three different twist geometries (“NearWake_TopPlanes” dataset) were subsequently studied to assess the influence of a twisted inflow. Twist influences secondary vorticity production on the surface of the sail and can be used to enhance the driving force of downwind sails. Further details can be found in the PhD thesis from Abel Arredondo-Galeana, “A study of the vortex flows of downwind sails”, available at the Edinburgh Research Archive repository. A manuscript describing the findings of this research is in preparation.

本研究加工了三款不同扭角设计的大三角帆原型，构建“Geometries”数据集，并采用粒子图像测速技术（Particle Image Velocimetry, PIV）对其近尾流开展研究。其中，参考帆（高扭角构型）于水槽均匀流场中完成测试，对应“Near Wake”数据集。该构型在表观风角为55°时可提供最大推进力。本数据集包含沿帆展向布置的5个PIV测量平面，分别标记为A、B、C、D、E，对应从帆底至帆尖距离的7/8、5/6、3/4、1/2及1/4位置，每个平面共采集500幅测速图像。该参考构型的详细信息可参见Arredondo-Galeana与Viola于2018年发表在《OE》期刊的论文。随后针对三款扭角构型的顶部测量平面（对应“NearWake_TopPlanes”数据集）展开研究，以评估扭转入流的影响。帆的扭角会影响帆表面的次生涡生成，可用于提升顺风帆的推进性能。更多细节可查阅Abel Arredondo-Galeana的博士学位论文《顺风帆涡流研究》（原标题："A study of the vortex flows of downwind sails"），该论文可在爱丁堡研究档案馆（Edinburgh Research Archive）获取。相关研究结果的学术论文尚在撰写中。

搜集汇总

背景与挑战

背景概述

该数据集通过粒子图像测速技术（PIV）研究顺风帆的涡流流动，包含三种不同扭曲度的帆形原型在近尾流区域的测量数据，具体涉及五个沿帆跨度分布的测量平面，每个平面记录500张图像，旨在分析扭曲度对涡度产生和帆驱动力的影响，以优化帆的设计。