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We present an experimental investigation of water flow around a hydrofoil with a superhydrophobic patterned surface. The experimental setup uses a water tunnel to measure the drag over the hydrofoil and acquire velocity field measurements using particle image velocimetry (PIV). Drag reduction on the order of 10% or higher was observed on hydrofoils with irregular surface textures combined with super-hydrophobic coating, leading to effective Navier slip on the surface. However, we report that other macroscopic flow characteristics, including the stall angle, are also changed by application of the coating.
drag reduction, experiment, particle image velocimetry, stall, superhydrophobic surface
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