Numerical simulations for the rheological characteristics of emulsions under several conditions including temperature, shear rate, surfactant concentration and droplet size

Se Bin Choi; Jung Shin Lee; Seung Joo Baik; Joon Sang Lee

Numerical simulations for the rheological characteristics of emulsions under several conditions including temperature, shear rate, surfactant concentration and droplet size

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Author(s): Se Bin Choi ¹ ; Jung Shin Lee ¹ ; Seung Joo Baik ¹ ; Joon Sang Lee ¹
- Affiliations: 1: Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Republic of Korea
Source: Volume 9, Issue 12, December 2014, p. 896 – 900
DOI: 10.1049/mnl.2014.0426 , Online ISSN 1750-0443

Received 10/07/2014, Accepted 17/10/2014, Revised 02/10/2014, Published 03/12/2014

An emulsion system was simulated under simple shear rates to analyse its rheological characteristics using the lattice Boltzmann method. The relative viscosity of an emulsion under a simple shear flow along with changes in temperature, shear rate, surfactant concentration and droplet size was calculated. The relative viscosity of emulsions decreased with increase in temperature. The shear thinning phenomena explaining the inverse proportion between shear rate and viscosity were observed. An increase in the surfactant concentration caused an increase in the relative viscosity for a decane-in-water emulsion, because the increased deformation caused by the decreased interfacial tension significantly influenced the wall shear stress. An increase in droplet size caused a decrease in the relative viscosity and smaller shear thinning behaviour because of decreased aggregational and repulsive forces within the emulsion system.

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Numerical simulations for the rheological characteristics of emulsions under several conditions including temperature, shear rate, surfactant concentration and droplet size

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