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Studying Large Amplitude Oscillatory Shear Response of Soft Materials
Published on: April 25, 2019
Dynamics of a deformable active particle under shear flow.
Mitsusuke Tarama1, Andreas M Menzel, Borge ten Hagen
1Department of Physics, Kyoto University, Kyoto 606-8502, Japan.
The Journal of Chemical Physics
|September 21, 2013
Summary
This study models deformable active particles in shear flow, revealing diverse motion modes like straight, periodic, and chaotic paths. These findings offer insights into active matter dynamics under external forces.
Area of Science:
- Physics of soft matter
- Fluid dynamics
- Nonlinear dynamics
Background:
- Understanding active particle behavior in complex flows is crucial for fields like microfluidics and biophysics.
- Deformable active particles exhibit complex dynamics influenced by both internal propulsion and external forces.
Purpose of the Study:
- To theoretically investigate the motion of a deformable active particle subjected to linear shear flow.
- To develop and analyze a nonlinear dynamical model capturing particle position, velocity, deformation, and rotation.
Main Methods:
- Derivation of coupled nonlinear dynamical equations based on symmetry considerations.
- Numerical solution of these equations in two spatial dimensions for various shear rates and propulsion speeds.
- Analysis of real-space trajectories and dynamical behavior of particle orientation and deformation.
Main Results:
- Identified a manifold of distinct dynamical modes: active straight motion, periodic, undulated cycloid, winding, quasi-periodic, and chaotic motions.
- Demonstrated that the model reduces to known limits for vanishing shear flow or particle deformability.
- Characterized different motion types by analyzing trajectories and particle orientation/deformation dynamics.
Conclusions:
- The theoretical model successfully predicts diverse and complex behaviors of deformable active particles in shear flow.
- The findings provide a framework for understanding active matter under flow conditions.
- Experimental verification using self-propelled droplets in linear shear flow is proposed.
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