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Updated: Jun 3, 2026
06:07
Studying Large Amplitude Oscillatory Shear Response of Soft Materials
Published on: April 25, 2019
The continuum theory of shear localization in two-dimensional foam
Denis Weaire1, Joseph D Barry, Stefan Hutzler
1School of Physics, Trinity College Dublin, Dublin 2, Republic of Ireland.
Summary
Recent advances in 2D liquid foam rheology reveal shear localization, impacting 3D foams and yield stress systems. A continuum model explains and predicts foam behavior, though simulation comparisons are ongoing.
Area of Science:
- Rheology
- Soft Matter Physics
- Material Science
Background:
- Two-dimensional liquid foams exhibit complex mechanical behaviors.
- Understanding yield stress in materials is crucial for various applications.
- Shear localization is a key phenomenon in foam rheology.
Purpose of the Study:
- To review recent advances in the rheology of two-dimensional liquid foams.
- To explore the implications of these advances for three-dimensional foams and yield stress systems.
- To analyze the phenomenon of shear localization under steady shear.
Main Methods:
- Review of experimental observations, including those by Debrégeas et al.
- Application and refinement of a continuum theory incorporating wall drag.
- Comparison of theoretical predictions with experimental results and quasistatic simulations.
Main Results:
- A continuum theory successfully reproduces shear localization in 2D foams.
- Refined models match extensive experimental data and predict behavior at low strain rates and for non-steady shear.
- The Herschel-Bulkley relation's origin in foam rheology remains an area of interest.
Conclusions:
- Continuum models provide a valuable semi-empirical framework for understanding 2D foam rheology.
- Further research is needed to reconcile model parameters with detailed simulations and experiments.
- The study highlights the predictive power and limitations of current rheological models for foams.
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