Abstract Flat plate models of fixed aspect ratio incorporating either serrations or holes at the upper and lower plate edges, were towed normal to the flow and in proximity to the free surface. The hydrodynamics and the drag generated by the plates has been studied in detail for several configurations. In general, the models with holes presented greater drag reduction than those with serrations, with the hole angle playing an important role on the total drag measured. The fluid dynamic sources for drag reduction at low submergence depths have been investigated using quantitative flow visualization, and they have been related to the changes in the separating shear layers, as a result of the different edge features imposed to the plates.

中文翻译：

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自由表面附近横流刚性板的被动减阻

摘要 固定纵横比的平板模型在上下板边缘包含锯齿或孔，被拖曳垂直于流动并靠近自由表面。已经针对几种配置详细研究了由板产生的流体动力学和阻力。一般来说，带孔的模型比带锯齿的模型具有更大的减阻效果，孔角度对测量的总阻力起着重要作用。已经使用定量流动可视化研究了低浸没深度下减阻的流体动力源，并且它们与分离剪切层的变化有关，这是由于施加到板的不同边缘特征。