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Experimental Study on Drag Reduction Characteristics of Bionic Earthworm Self-Lubrication Surface
Guomin Liu1,2, Xueqiao Wu3, Meng Zou3
1College of Civil Engineering, Jilin Jianzhu University, Changchun 130118, China.
Applied Bionics and Biomechanics
|November 30, 2019
Summary
This study demonstrates significant drag reduction (22.65%-34.89%) using a bionic corrugated surface with lubrication, inspired by earthworm skin. Optimal performance depends on managing normal pressure, lubricant flow, and forward velocity.
Area of Science:
- Fluid Dynamics
- Biomimetics
- Surface Engineering
Background:
- Drag reduction is crucial for energy efficiency in various applications.
- Bionic designs offer novel approaches to fluid resistance mitigation.
- Earthworm skin exhibits unique surface properties that inspire bio-inspired engineering solutions.
Purpose of the Study:
- To investigate the drag reduction characteristics of a bionic corrugated surface combined with lubrication.
- To analyze the influence of key operational parameters on the performance of the bionic surface.
- To develop a predictive model for forward resistance based on experimental data.
Main Methods:
- A coupling bionic method integrating earthworm surface morphology and lubrication.
- Reverse engineering to extract earthworm surface features for bionic sample design.
- Single-factor and ternary quadratic regression tests using self-developed equipment to analyze drag reduction performance.
- Experimental determination of lubrication hole positions.
Main Results:
- Achieved significant drag reduction rates ranging from 22.65% to 34.89%.
- Forward resistance decreased with increasing forward velocity.
- Forward resistance increased with increasing normal pressure.
- Forward resistance initially decreased and then stabilized with increasing lubricating fluid flow rate.
- Established the order of influence for key factors on forward resistance: normal pressure > flow rate of lubricating fluid > forward velocity.
Conclusions:
- The bionic corrugated surface with lubrication effectively reduces drag.
- Operational parameters significantly influence the drag reduction performance.
- The developed model provides insights into optimizing bionic surface applications for enhanced efficiency.
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