Multiscale Analysis of Water-in-Oil Emulsions: A Computational Fluid Dynamics Approach

Emulsions are a type of metastable colloid composed of two or more immiscible liquids. These systems are widely used in a variety of applications, such as cosmetics, drug delivery, food, etc. Although there exist theoretical foundations which offer insights into these systems, industry practices often favor empirical methods. In this work a multiscale approximation is used for the study of water-in-oil (W/O) emulsions. This approach allows for the analysis of interrelationships among macroscopic, microscopic, process, and formulation variables. Additionally, the emulsions were modeled with Computational Fluid Dynamics (CFD), which permitted a better understanding of the role process variables plays. It was possible to establish relationships among incorporated energy, elastic modulus, mean droplet diameter, and stability measurements. In addition, differences in impeller geometry were found to have an effect in the aforementioned variables. Finally, the CFD model allowed for the observation of gradients in relative viscosity, droplet diameter, and dispersed phase volume fraction.