Stress fluctuations in sheared Stokesian suspensions
J Dasan1, T R Ramamohan, Anugrah Singh
1Computational Materials Science, Unit-I, Regional Research Laboratory (CSIR), Thiruvananthapuram 695 019, India.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 21, 2002
Summary
We analyzed chaotic stress fluctuations in simulated suspensions. Higher particle concentrations lead to more complex dynamics, revealing insights into suspension behavior and microstructure.
Area of Science:
- Fluid dynamics
- Nonlinear dynamics
- Chaos theory
Background:
- Stokesian suspensions exhibit complex rheological behavior.
- Understanding stress fluctuations is crucial for characterizing suspension dynamics.
Purpose of the Study:
- To analyze stress fluctuations in simulated shear flow of Stokesian suspensions.
- To characterize the underlying dynamics of these fluctuations using chaos theory.
- To investigate the relationship between particle concentration and suspension behavior.
Main Methods:
- Simulations of shear flow between parallel walls for suspensions of rigid spheres in a Newtonian fluid.
- Time series analysis of stress fluctuations.
- Application of nonlinear dynamics and chaos theory tools, including dynamic and metric invariants.
Main Results:
- Stress fluctuations in these suspensions are deterministic, low-dimensional, and chaotic.
- The dimension of the chaotic attractor increases with particle concentration.
- Accurate short-term predictions of stress evolution were achieved.
Conclusions:
- Chaos theory provides a powerful framework for understanding suspension rheology.
- Increased particle concentration enhances multi-body interactions, influencing chaotic dynamics.
- The study links microscopic interactions to macroscopic stress behavior in suspensions.
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