Paper Number
EF4 

Session
Emulsions, Foams and Interfacial Rheology

Title
Universal scaling characteristics of stress relaxation in jammed emulsions

Presentation Date and Time
October 7, 2014 (Tuesday) 5:15

Track / Room
Track 6 / Washington C

Authors (Click on name to view author profile)

1. Boukany, Pouyan (Delft University of Technology, Chemical Engineering Department)
2. Vasudevan, Siddarth (Delft University of Technology, Chemical Engineering Department)
3. Tighe, Brian (Delft University of Technology, Chemical Engineering Department)

Author and Affiliation Lines (in printed abstract book)
Pouyan Boukany, Siddarth Vasudevan, and Brian Tighe
Chemical Engineering Department, Delft University of Technology, Delft 2628 BL, The Netherlands

Speaker / Presenter 
Boukany, Pouyan

Text of Abstract
We study the stress relaxation behaviour of jammed emulsions both by experiments and simulations. The relaxation of scaled shear modulus is found to obey a power law behaviour. We demonstrate that the only parameters determining the relaxation behaviour are the exponent in the power law and average relaxation time for a given volume fraction. We find that exponent is 0.5 and 1 for linear and non-linear response regime respectively. Relaxation time is nearly independent of the applied strain for given volume fraction and it is the average value of the relaxation time obtained for different strains which determines the overall relaxation behaviour of a jammed emulsion. The average relaxation time is found to decrease with increase in the distance from the jamming transition point and obeys a scaling relationship, which is consistent with analytical predictions. We observe strain softening of the shear modulus and found that it scales inversely with strain in the non-linear response regime.