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Updated: Jun 29, 2025
08:04
Controlling Flow Speeds of Microtubule-Based 3D Active Fluids Using Temperature
Published on: November 26, 2019
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Hydrodynamically induced aggregation of two dimensional oriented active particles
Roee Bashan1, Naomi Oppenheimer1
1School of Physics and Astronomy and the Center for Physics and Chemistry of Living Systems, Tel Aviv University, Israel. naomiop@gmail.com.
Soft Matter
|March 27, 2024
Summary
Active particles in fluid form stable, fractal-like aggregations due to hydrodynamic and steric interactions. This study introduces a new method for analyzing flow fields and their spatial decay dynamics.
Area of Science:
- Physics
- Fluid Dynamics
- Statistical Mechanics
Background:
- Active particles in fluids exhibit complex behaviors.
- Hydrodynamic and steric interactions govern particle dynamics.
- Understanding emergent patterns is crucial in soft matter physics.
Purpose of the Study:
- To develop a novel method for calculating fluid flow generated by active particles.
- To analyze the dynamics of flow fields with high-order spatial decay.
- To investigate the aggregation patterns of co-oriented active particles.
Main Methods:
- Analysis of hydrodynamic and steric interactions.
- Utilizing a geometric Hamiltonian for flow field dynamics.
- Investigating high-order spatial decay of flow fields.
Main Results:
- A new method for calculating active particle-induced flow is presented.
- Co-oriented active particles form stable, fractal-like aggregations.
- The aggregation is linked to odd power decay in flow fields, with force dipoles as an exception.
Conclusions:
- The findings reveal mechanisms for self-organization in active matter systems.
- The developed method offers a versatile tool for analyzing similar systems.
- Results are generalizable to more complex force distributions and 2D systems.
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