The hydrophobicity of water striders and fisher spiders shows the geometrical property of microsetae with elaborate nanogrooves. Studying such geometrical morphology naturally leads to the question: what is an optimal shape for buoyancy? In this paper, we present a methodology to find suboptimal shapes for star-shaped cross-sectional rods, which maximizes the buoyant force by modeling the cross-sectional shapes with Fourier series representation in the polar coordinate. We provide four suboptimal cross-sectional shapes and their experimental results. Our results support the importance of the geometrical shape for buoyant force and might be helpful in designing water repelling devices.
Issue Section:
Fundamental Issues and Canonical Flows
Keywords:
Fourier series,
hydrophobicity,
shapes (structures),
Fourier series,
hydrophobicity,
buoyant force,
contact angle,
multiwalled carbon nanotubes,
shape optimization
Topics:
Buoyancy,
Fourier series,
Hydrophobicity,
Shape optimization,
Shapes,
Water,
Modeling,
Rods,
Approximation
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.Copyright © 2010
by American Society of Mechanical Engineers
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