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09:58
Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
An asymmetry model for the highly viscous flow
1Institut für Festkörperforschung, Forschungszentrum Jülich, Postfach 1913, D-52425 Jülich, Germany. buchenau-juelich@t-online.de
The Journal of Chemical Physics
|August 28, 2009
Summary
This study models shear flow using local structural rearrangements, explaining how asymmetry and elastic misfit drive system evolution over time. The findings elucidate Kohlrausch behavior through the interplay of these rearrangements.
Area of Science:
- Materials Science
- Rheology
- Polymer Physics
Background:
- Shear flow in materials is often governed by complex molecular or structural rearrangements.
- Understanding the dynamics of these rearrangements is crucial for predicting material behavior under stress.
- Elastic properties of the surrounding matrix significantly influence local structural changes.
Purpose of the Study:
- To develop a model for shear flow based on local structural rearrangements.
- To investigate the role of asymmetry and elastic misfit in these rearrangements.
- To explain the observed Kohlrausch behavior in materials.
Main Methods:
- Modeling shear flow through local structural rearrangement dynamics.
- Analyzing the asymmetry of rearrangements due to elastic adaptation and misfit.
- Investigating time-dependent asymmetry approaching Maxwell time.
- Correlating local rearrangement interactions with Kohlrausch behavior.
Main Results:
- Most local structural rearrangements during shear flow are strongly asymmetric.
- Elastic misfit between the matrix and the rearranging structure drives system evolution.
- Time-dependent asymmetry near Maxwell time allows the system to transition from its initial state.
- The interaction of multiple local rearrangements explains the Kohlrausch relaxation observed in the main peak.
Conclusions:
- Local structural rearrangements, particularly their asymmetry and elastic misfit, are key to understanding shear flow dynamics.
- The model successfully explains the Kohlrausch behavior by considering the collective interactions of these rearrangements.
- This work provides a framework for analyzing complex material responses to shear stress.
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