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Analytical model for drag reduction on liquid-infused structured non-wetting surfaces
1Advanced Materials and Technologies Laboratory Department of Mechanical Engineering Virginia Tech Blacksburg, Virginia 24061-0238, USA. pitchu@vt.edu.
Soft Matter
|December 16, 2020
Summary
This study introduces an analytical model for liquid-infused structured surfaces, enabling precise calculation of drag reduction. The model accurately predicts friction reduction without empirical fitting, offering broad engineering applications.
Area of Science:
- Fluid dynamics
- Surface science
- Tribology
Background:
- Liquid-infused structured non-wetting surfaces create alternating no-slip and partial slip conditions.
- These conditions reduce fluid flow friction at interfaces.
Purpose of the Study:
- Develop an analytical model to evaluate effective slip and predict drag reduction.
- Eliminate empirical fitting by considering surface anisotropy, heterogeneity, and liquid slip range.
Main Methods:
- Analytical modeling of fluid flow over structured surfaces.
- Calculation of effective slip length, friction factor, and drag reduction.
- Validation against experimental and computational data.
Main Results:
- Presents drag reduction and skin friction coefficient for Newtonian flow in parallel plates and round tubes.
- Extends Moody charts for non-wetting surfaces.
- Provides design maps for surface texturing to achieve specific drag reduction.
Conclusions:
- The developed model offers a unified approach to understanding drag reduction on liquid-infused surfaces.
- It eliminates reliance on empirical correlations, providing a more fundamental understanding.
- The findings support the design of advanced surfaces for various engineering applications.
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