Microspheres viscous drag at a deformed fluid interface: particle's weight and electrical charges effects
Nadia Ben'MBarek1, Adel Aschi1, Christophe Blanc2
1Faculté des Sciences de Tunis, Université de Tunis El Manar, LR99ES16 Laboratoire Physique de la Matière Molle et de la Modélisation Électromagnétique, 2092, Tunis, Tunisia.
The European Physical Journal. E, Soft Matter
|March 10, 2021
Summary
Particle charge and weight deform fluid interfaces, influencing microparticle diffusion. Researchers analytically predict diffusion coefficients based on interface deformation and particle dynamics, aiding future experimental comparisons.
Area of Science:
- Physics, Soft Matter
- Colloid and Interface Science
Background:
- Microparticles trapped at fluid interfaces experience deformation due to their electrical charge and weight.
- This interface deformation is hypothesized to alter particle diffusion dynamics through modified hydrodynamic boundary conditions.
Purpose of the Study:
- To analytically predict the diffusion coefficient of microparticles at fluid interfaces.
- To investigate the influence of particle-induced electrostatic deformation on particle diffusion.
Main Methods:
- Utilized existing models for particle-induced electrostatic deformation of fluid interfaces.
- Applied models of particle dynamics at interfaces.
- Performed analytical predictions of particle diffusion coefficients.
Main Results:
- Successfully predicted particle diffusion coefficient values across a wide range of particle contact angles and sizes.
- Demonstrated a quantitative relationship between interface deformation and particle diffusion.
Conclusions:
- The analytical predictions provide a theoretical framework for understanding microparticle diffusion at deformable interfaces.
- Offers a valuable benchmark for comparison with future experimental studies in microparticle dynamics at fluid interfaces.
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