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Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
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Unified Understanding of Nonlinear Rheology near the Jamming Transition Point.
Takeshi Kawasaki1, Kunimasa Miyazaki1
1Department of Physics, <a href="https://ror.org/04chrp450">Nagoya University</a>, Nagoya 464-8602, Japan.
Physical Review Letters
|July 12, 2024
Summary
Jammed packings exhibit elastic responses before yielding. Researchers found universal scaling in shear stress and pressure, revealing shear softening over a wide strain range, which helps explain nonlinear rheologies in soft materials.
Area of Science:
- Soft matter physics
- Materials science
- Rheology
Background:
- Jammed packings exhibit elastic behavior under shear before yielding.
- Nonlinear rheologies like shear softening emerge as the jamming transition is approached.
- The physical mechanisms behind these nonlinear rheologies are not fully understood.
Purpose of the Study:
- To numerically investigate the physical mechanisms of nonlinear rheologies in jammed packings.
- To clarify the universal scaling behavior of shear stress and pressure under quasistatic shear.
- To understand shear softening in athermal frictionless soft particle systems.
Main Methods:
- Numerical simulations of jammed packings of soft particles.
- Application of quasistatic shear (γ).
- Analysis of shear stress (σ) and pressure (P) relationships.
Main Results:
- Identified universal scaling behavior for the ratio of shear stress to pressure (σ/P).
- This scaling is independent of the initial configuration preparation protocol.
- Revealed shear softening with the relationship σ/P∼γ^{1/2} over a wide strain range up to the yielding point.
Conclusions:
- The study provides a rationalization for shear softening in jammed soft materials.
- The findings offer insights into the fundamental physics governing the nonlinear rheological properties of soft matter.
- The universal scaling behavior is a key characteristic of jammed systems near the jamming transition.
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