Related Experiment Video
Updated: Jan 29, 2026
07:58
Bio-inspired Polydopamine Surface Modification of Nanodiamonds and Its Reduction of Silver Nanoparticles
Published on: November 14, 2018
8.7K
Fabrication and Drag Reduction Performance of Flexible Bio-Inspired Micro-Dimple Film
Yini Cai1, Yanjun Lu1, Haopeng Gan1
1Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering, College of Mechatronics and Control Engineering, Shenzhen University, Shenzhen 518000, China.
Micromachines
|January 28, 2026
Summary
Researchers developed a flexible polymer film with bio-inspired micro-dimples for drag reduction. Optimized manufacturing achieved high shape accuracy and validated significant drag reduction, showing promise for aerospace and marine applications.
Area of Science:
- Materials Science
- Fluid Dynamics
- Biomimetics
Background:
- Biological skins possess micro-structured surfaces that effectively reduce drag.
- Replicating these bio-inspired surfaces efficiently is crucial for technological applications.
Purpose of the Study:
- To develop a composite flexible polymer film with a bio-inspired micro-dimple array.
- To investigate the influence of manufacturing parameters on film quality and drag reduction.
- To validate the performance of the fabricated film through simulation and experiment.
Main Methods:
- Fabrication using precision milling, polishing, and micro-injection molding of thermoplastic polyurethane (TPU).
- Systematic investigation of injection molding parameters (melt temperature, holding time, injection speed).
- Numerical simulation and experimental validation of drag reduction performance.
Main Results:
- Polishing significantly improved mold core surface roughness and film replication accuracy.
- Melt temperature and holding time were key parameters affecting shape precision and roughness.
- Optimized conditions yielded a micro-structure shape accuracy of 13.502 μm and bottom roughness of 0.033 μm.
- Numerical simulations predicted a maximum drag reduction of 10.26% due to vortex cushion effects.
- Experimental validation confirmed drag reduction within 5% of simulation results across tested flow velocities.
Conclusions:
- The integrated manufacturing process is effective for producing flexible bio-inspired drag reduction films.
- The fabricated film demonstrates significant drag reduction capabilities, validated by simulation and experiment.
- This technology holds potential for applications in aerospace, underwater exploration, and pipeline transportation.
Related Concept Videos
01:23Drag
395
Drag is a resistive force opposing an object’s motion through a fluid, resulting from surface pressure and shear forces. It comprises two components: a perpendicular one from pressure and a tangential one from shear stress. Accurate drag calculations use pressure and wall shear stress distributions, often determined through Computational Fluid Dynamics (CFD) or wind tunnel testing. The drag coefficient, a dimensionless measure, depends on factors like shape, Reynolds number, Mach number,...
395
01:18Drag Force and Terminal Speed
3.4K
An interesting force in everyday life is the force of drag on an object when it is moving in a fluid. Like friction, the drag force always opposes the motion of an object. Unlike simple friction, the drag force is proportional to some function of the velocity of the object in that fluid. This functionality is complicated and depends upon the shape of the object, its size, its velocity, and the fluid it is in. For most large objects, such as cyclists, cars, and baseballs, that are not moving too...
3.4K
01:30Mechanism of Breathing I: Inspiration
3.1K
Introduction to Inspiration: The Respiratory System in Action
The respiratory system, an essential network for breathing, comprises the conducting and respiratory zones, each playing a crucial role in the overall process of respiration. Let us explore the detailed mechanism of inspiration, or inhalation, which is the first phase of the respiratory cycle.
Pathway of Air during Inspiration
During inspiration, air enters our body through the nose or mouth and moves through the conducting zone,...
The respiratory system, an essential network for breathing, comprises the conducting and respiratory zones, each playing a crucial role in the overall process of respiration. Let us explore the detailed mechanism of inspiration, or inhalation, which is the first phase of the respiratory cycle.
Pathway of Air during Inspiration
During inspiration, air enters our body through the nose or mouth and moves through the conducting zone,...
3.1K
03:11Oxidation-Reduction Reactions
75.5K
Oxidation–Reduction Reactions
75.5K
02:36Oxymercuration-Reduction of Alkenes
9.3K
Oxymercuration–reduction of alkenes is one of the major reactions converting alkenes to alcohols. It involves the hydration of alkenes with mercuric acetate in a mixture of tetrahydrofuran and water, forming an organomercury adduct. This is followed by a demercuration step in which the adduct is reduced to an alcohol using sodium borohydride.
9.3K
01:22Block Diagram Reduction
553
The process of deriving the transfer function of a control system often involves reducing its block diagram to a single block. This simplification can be achieved through a series of strategic operations, including relocating branch points and comparators. These operations preserve the overall function of the system while allowing for easier manipulation and combination of blocks.
The first step in this process is the identification and relocation of a branch point. A branch point, where a...
The first step in this process is the identification and relocation of a branch point. A branch point, where a...
553