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Giant stress fluctuations at the jamming transition
Didier Lootens1, Henri Van Damme, Pascal Hébraud
1P.P.M.D., CNRS UMR 7615, ESPCI, 10 rue Vauquelin 75231, Paris Cedex 05, France.
Physical Review Letters
|June 6, 2003
Summary
We observed giant stress fluctuations in concentrated colloidal suspensions under shear. These fluctuations follow power-law behavior, leading to a new flow branch with periodic, high-amplitude events.
Area of Science:
- Rheology
- Colloidal Science
- Soft Matter Physics
Background:
- Concentrated colloidal suspensions exhibit complex flow behaviors.
- Understanding stress response is crucial for predicting material properties.
Purpose of the Study:
- To investigate the stress response of colloidal suspensions under steady shear.
- To characterize the nature and behavior of stress fluctuations.
Main Methods:
- Imposing a steady shear rate on concentrated colloidal suspensions.
- Analyzing stress fluctuations and their amplitude distribution.
Main Results:
- Observed giant stress fluctuations within a specific range of concentrations and shear rates.
- Fluctuation amplitude follows a power-law relationship.
- Identified a new flow branch characterized by periodic, high-amplitude fluctuations.
Conclusions:
- The study reveals unique stress dynamics in concentrated colloidal suspensions.
- Power-law behavior and emergent periodic flow highlight complex rheological transitions.
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