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On-demand zero-drag hydrodynamic cloaks resolve D'Alembert paradox in viscous potential flows
Neng-Zhi Yao1, Bin Wang2, Hao Wang1
1School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China.
Microsystems & Nanoengineering
|December 12, 2024
Summary
Researchers developed a novel hydrodynamic cloak using viscosity, achieving zero drag and resolving the D'Alembert paradox. This breakthrough offers controllable fluid manipulation for energy and biomedical applications.
Area of Science:
- Fluid dynamics
- Hydrodynamics
- Viscosity
Background:
- The D'Alembert paradox and unresolved Navier-Stokes solutions pose significant challenges in fluid dynamics.
- Developing hydrodynamic zero-drag cloaks is crucial for energy efficiency and advanced engineering applications.
- Current limitations hinder the realization of effective drag reduction across various flow conditions.
Purpose of the Study:
- To introduce a novel paradigm for hydrodynamic zero-drag cloaks.
- To investigate the role of isotropic and homogeneous viscosity in achieving zero-drag properties.
- To demonstrate the controllable activation and deactivation of hydrodynamic concealment.
Main Methods:
- Experimental validation of the proposed cloak design.
- Numerical simulations to analyze flow dynamics and cloaking effects.
- Focus on manipulating vorticity for drag reduction and cloaking.
Main Results:
- The developed cloaks exhibit zero-drag properties in viscous potential flows.
- The D'Alembert paradox is effectively resolved by the proposed cloak.
- Hydrodynamic concealment can be activated or deactivated at will.
Conclusions:
- Controlling vorticity is essential for active hydrodynamic zero-drag cloak designs.
- The study challenges the notion of impossibility of zero drag in fluid mechanics.
- Findings have implications for microfluidics, biofluidics, and hypervelocity technologies.
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