Viscous friction in foams and concentrated emulsions under steady shear.
نویسندگان
چکیده
We present a model for the viscous friction in foams and concentrated emulsions, subject to steady shear flow. First, we calculate the energy dissipated due to viscous friction inside the films between two neighboring bubbles or drops, which slide along each other in the flow. Next, from this energy we calculate the macroscopic viscous stress of the sheared foam or emulsion. The model predictions agree well with experimental results obtained with foams and emulsions.
منابع مشابه
Theoretical model of viscous friction inside steadily sheared foams and concentrated emulsions.
In a recent Letter [N. D. Denkov, Phys. Rev. Lett. 100, 138301 (2008)] we calculated theoretically the macroscopic viscous stress of steadily sheared foam or emulsion from the energy dissipated inside the transient planar films, formed between neighboring bubbles or drops in the shear flow. The model predicts that the viscous stress in these systems should be proportional to Ca 1/2, where Ca is...
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عنوان ژورنال:
- Physical review letters
دوره 100 13 شماره
صفحات -
تاریخ انتشار 2008