Improving Groundwater Remediation: Elastic Turbulence-Induced Scalar Mixing

Abstract

Polymer solutions are often injected into aquifers in groundwater remediation to improve the transport of treatment chemicals to non-aqueous contaminants. The accumulation of elastic stresses in polymers induces fluctuations that can drastically impact flow patterns, potentially altering macroscopic flow pathways and improving scalar mixing. However, the relationship between flow structure and mixing behavior in porous media remains unexplored. My research defines a general framework to develop a model for mixing in elastically unstable flow, by providing a refined design of model porous media to test this relationship and defining methods to elucidate the role of key tuning parameters—such as flowrate, elasticity, and pore geometry—in scalar mixing in porous media. Dispersion is experimentally shown to be clearly improved by the addition of polymers. My research provides a clear direction to model mixing in polymer flow, and ultimately to leverage flow structure to redirect transport of treatment chemicals to bypassed regions of contaminants throughout porous media by using polymer solutions in groundwater remediation.