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Updated: Jul 1, 2025
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Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
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EHD instability of a cylindrical interface separating two couple-stress fluids.
Galal M Moatimid1, Mohamed F E Amer2, Doaa A Ibrahim3
1Department of Mathematics, Faculty of Education, Ain Shams University, Roxy, Cairo, Egypt.
Scientific Reports
|March 7, 2024
Summary
This study investigates fiber-reinforced composite fluids (CSFs) and their stability. The presence of porous materials significantly increases instability in CSF systems, particularly for axisymmetric disturbances.
Area of Science:
- Fluid dynamics
- Materials science
- Rheology
Background:
- Fiber-reinforced composite substances (CSFs) are crucial in modern manufacturing and technology.
- Understanding the flow behavior and stability of CSFs is essential for their application.
- Existing research necessitates further investigation into the complex dynamics of these fluids.
Purpose of the Study:
- To examine axi-symmetric and asymmetric streaming flows within the CSF framework.
- To analyze the influence of an axial electric field (EF) and porous media on CSF stability.
- To develop linear stability criteria and investigate dispersion relationships.
Main Methods:
- Utilizing the Velocity-Potential Transformation (VPT) to simplify mathematical complexity.
- Applying linear techniques by combining equations of motion and boundary conditions (BCs).
- Employing Gaster's theorem and Marginal Stability (MS) analysis for dispersion relationships.
Main Results:
- A set of physically dimensionless numbers was derived through non-dimensionalization.
- The presence of porous material was found to destabilize the CSF system.
- Axisymmetric disturbances were shown to be more unstable compared to the absence of porous media.
Conclusions:
- Porous materials significantly enhance the instability of fiber-reinforced composite fluid systems.
- The study provides insights into the linear stability of CSFs under various conditions.
- Graphical representations illustrate the impact of different factors on system stability.
Keywords:
Couple-stress fluidsElectrohydrodynamicsHydrodynamic instabilityPorous mediaViscous potential theoryMore Related Videos
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