Modeling Flow-Induced Microstructure of Inhomogeneous Liquid-Liquid Mixtures

Liquid-liquid dispersions are found commonly in nature and industry. As these dispersions flow, the microstructure changes due to deformation and breakup processes at the microscale. The ability to predict this microstructural evolution has many applications, including controlling properties in polymer blends, predicting earthquake aftershocks, and modeling the flow of biological fluids. In order to model these systems, an exact Stokes flow solution is found for the deformation of a Newtonian droplet suspended in a Newtonian fluid with a different viscosity, for the case of negligible interfacial tension. Using this theory, we are able to predict droplet stretching, reorientation, and tumbling, and can quantitatively replicate available experimental observations of droplet behavior. A rheological theory for dilute dispersions is also derived which explicitly includes the effects of microstructure on the dispersion rheology. Example calculations show that, even in simple flows, microstructural effects can cause complex rheological behaviors in dispersions. Finally, these models are applied to complex flows of dispersions using the finite element method. Microstructure is predicted as a field variable in temporally- and spatially-varying flows, providing important new insights into microstructural development in dispersions.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Wetzel, Eric Dean

Contributors dc:contributor

• Tucker, Charles L., III

• Physics, Fluid and Plasma

Language dc:language

eng

Identifier

(MiAaPQ)AAI9945026

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/83987