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Coupled Bionic Drag-Reducing Surface Covered by Conical Protrusions and Elastic Layer Inspired from Pufferfish Skin
Xiaoming Feng1, Dongliang Fan1, Guizhong Tian1
1College of Mechanical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, China.
ACS Applied Materials & Interfaces
|July 11, 2022
Summary
Inspired by pufferfish, a new biomimetic surface with conical protrusions and an elastic layer significantly reduces drag in marine applications. This robust surface offers substantial drag reduction in both laminar and turbulent flows.
Area of Science:
- Materials Science
- Fluid Dynamics
- Biomimetics
Background:
- Marine engineering materials face challenges with drag reduction.
- Pufferfish skin inspires drag-reducing strategies through its spines and elastic properties.
Purpose of the Study:
- To develop and investigate a novel biomimetic surface (CPES) for drag reduction.
- To analyze the drag reduction mechanisms in laminar and turbulent flows.
- To evaluate the robustness and adhesion of the developed surface.
Main Methods:
- A hybrid method combining sintering and coating processes was used to create the CPES surface on a copper substrate.
- Rheometer and particle image velocimetry (PIV) experiments were conducted to measure drag reduction.
- Comparative analysis was performed using various substrate configurations (PCS, CS, CPRS, CPPCS).
Main Results:
- In laminar flow, the CPES surface achieved 7-8% drag reduction due to surface structure and wettability, inducing slip.
- In turbulent flow, the CPES surface demonstrated 11.5-17.5% drag reduction.
- Mechanisms include vortex generation by conical protrusions and energy dissipation of large vortices.
- The elastic layer exhibited high adhesion and stability under abrasion and erosion tests.
Conclusions:
- The developed CPES biomimetic surface effectively reduces drag in both laminar and turbulent flows.
- The combination of conical protrusions and an elastic layer provides a robust and efficient solution for underwater drag reduction.
- This research offers new insights for designing advanced marine engineering materials.
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