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Drag reduction using lubricant-impregnated surfaces in viscous laminar flow
Brian R Solomon1, Karim S Khalil, Kripa K Varanasi
1Department of Mechanical Engineering, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Langmuir : the ACS Journal of Surfaces and Colloids
|August 22, 2014
Summary
Lubricant-impregnated surfaces (LIS) can significantly reduce drag in laminar flows. This study shows drag reduction depends on lubricant viscosity, achieving 16% reduction with a 260:1 viscosity ratio.
Area of Science:
- Fluid Dynamics
- Surface Science
- Tribology
Background:
- Lubricant-impregnated surfaces (LIS) offer robust, superslippery properties.
- LIS utilize micro/nanotextured surfaces infused with lubricating liquids.
- Potential applications span various fluid flow scenarios.
Purpose of the Study:
- To systematically demonstrate the drag reduction potential of LIS in laminar flows.
- To develop a scaling model for drag reduction in LIS.
- To elucidate the dependence of drag reduction on lubricant and working fluid viscosity.
Main Methods:
- Development of a scaling model incorporating lubricant viscosity.
- Experimental validation using a cone and plate rheometer.
- Systematic variation of the viscosity ratio between working fluid and lubricant.
Main Results:
- A scaling model was developed, predicting drag reduction based on viscosity ratios.
- Experimental validation confirmed the model's predictions.
- Achieved 16% drag reduction with a slip length of 18 μm.
Conclusions:
- LIS effectively reduce drag in laminar flows.
- Drag reduction is strongly dependent on the viscosity ratio of the working fluid to the lubricant.
- The developed model provides a framework for optimizing LIS for specific flow conditions.
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