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Challenges in Rheological Characterization of Highly Concentrated Suspensions — A Case Study for Screen-printing Silver Pastes
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Scaling Description of Frictionless Dense Suspensions under Inhomogeneous Flow
Bhanu Prasad Bhowmik1, Christopher Ness1
1School of Engineering, University of Edinburgh, Edinburgh EH9 3JL, United Kingdom.
Physical Review Letters
|April 2, 2024
Summary
Researchers developed new constitutive laws for dense suspensions, unifying rheology under homogeneous and inhomogeneous flow. This framework predicts suspension behavior using particle velocity fluctuations and other key parameters.
Area of Science:
- Rheology
- Computational physics
- Materials science
Background:
- Predicting dense suspension rheology under inhomogeneous flow is challenging.
- Existing models like the μ(J) framework are limited to homogeneous conditions.
Purpose of the Study:
- To develop new constitutive laws for dense suspensions applicable to both homogeneous and inhomogeneous flow.
- To unify the rheological response of frictionless dense suspensions.
Main Methods:
- Particle-based simulations of frictionless dense suspensions.
- Derivation of new scaling relations incorporating particle velocity fluctuations.
Main Results:
- Developed novel constitutive laws that unify rheological response.
- Introduced a new dimensionless number based on particle velocity fluctuations.
- Achieved data collapse from homogeneous and inhomogeneous simulations.
Conclusions:
- The new framework accurately predicts steady-state velocity, stress, and volume fraction fields.
- This advances the understanding and prediction of dense suspension behavior in complex flows.
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