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Updated: Mar 18, 2026
07:23
Light-induced Patterning and Grafting for Slippery Surfaces based on Silane-coated Nanoporous Structures
Published on: November 14, 2025
531
Bioinspired surfaces for turbulent drag reduction
Kevin B Golovin1, James W Gose2, Marc Perlin2
1Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
Summary
Superhydrophobic surfaces (SHSs) can reduce friction drag in turbulent flow. Optimal SHSs require streamwise-aligned features, high capillary resistance, and minimal roughness for effective drag reduction.
Area of Science:
- Fluid dynamics
- Surface science
- Materials science
Background:
- Superhydrophobic surfaces (SHSs) are known for drag reduction in laminar flow.
- Turbulent flow presents unique challenges for SHS performance.
- Biomimetic and scalable SHSs have complex textures.
Purpose of the Study:
- To review the design principles of SHSs for friction drag reduction in turbulent flow.
- To analyze computational and experimental studies on SHS drag in turbulence.
- To identify key parameters for effective drag reduction using SHSs.
Main Methods:
- Review of existing literature on SHS design and performance.
- Analysis of computational fluid dynamics (CFD) simulations.
- Examination of experimental studies on SHS drag reduction.
Main Results:
- Streamwise and spanwise slip effects are characterized for simple SHSs.
- Complex textures of scalable SHSs can lead to no drag reduction or even drag increase.
- Surface wettability, roughness, and scaling laws influence SHS performance in turbulence.
Conclusions:
- Effective SHSs for turbulent flow need streamwise-aligned features for enhanced slip.
- High capillary resistance (megapascals) and low non-dimensional roughness (≤0.5) are crucial.
- Understanding surface properties is key to overcoming challenges in turbulent drag reduction.
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