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Beating patterns of filaments in viscoelastic fluids
Henry C Fu1, Charles W Wolgemuth, Thomas R Powers
1Division of Engineering, Brown University, Providence, Rhode Island 02912, USA. Henry_Fu@brown.edu
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 13, 2008
Summary
Viscoelastic fluids alter the motion of swimming microorganisms like sperm by changing hydrodynamic forces on their flagella. This can concentrate movement at the flagellar tip, mimicking observed sperm swimming patterns.
Area of Science:
- Fluid dynamics
- Biophysics
- Microbiology
Background:
- Microorganisms like bacteria and sperm navigate viscoelastic environments using flagella.
- Understanding flagellar propulsion in complex fluids is crucial for biological and micro-robotic applications.
Purpose of the Study:
- To investigate how viscoelasticity affects the motion and beating patterns of elastic filaments.
- To analyze the impact of modified hydrodynamic forces on filament dynamics.
Main Methods:
- Modeling passive filaments actuated at one end.
- Modeling active filaments with internal motor-generated bending forces.
- Analyzing the influence of fluid viscoelasticity on force-pattern dynamics.
Main Results:
- Viscoelasticity significantly modifies hydrodynamic forces on filaments.
- Modified forces lead to altered flagellar beating patterns.
- High viscosity in solutions can induce sperm-like flagellar beating patterns.
Conclusions:
- Fluid viscoelasticity plays a key role in modulating microorganism locomotion.
- The study provides insights into the mechanics of flagellar propulsion in complex biological fluids.
- Findings can inform the design of micro-swimmers and understanding of biological motility.
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