Article

Viscous friction in foams and concentrated emulsions under steady shear.

Laboratory of Chemical Physics & Engineering, Faculty of Chemistry, Sofia University, Bulgaria.
Physical Review Letters (Impact Factor: 7.73). 04/2008; 100(13):138301. DOI: 10.1103/PhysRevLett.100.138301
Source: PubMed

ABSTRACT 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.

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