Unveiling air sparging analysis in flow cells through the continuum approach

We present various analytical solutions for a two-dimensional steady air source that demonstrate classical flow physics’ usefulness in air-sparging evaluation. These solutions capture different flow geometry and setup effects while offering accuracy, speed, and a deeper understanding of governing physics. Compared to empirical models, they excel with fewer physical parameters. We validate their accuracy by comparing these solutions to experimental air-sparging data from two-dimensional flow cells. This comparison underscores the applicability of the physical model and establishes a relationship between grain size and a key model parameter. Furthermore, this analysis enables predictive capabilities for scaled-up systems with diverse setup geometries.

Plain Language Summary Air-sparging refers to the injection of air below the groundwater table, that is, to the water-saturated section of the aquifer. Air-sparging is used to facilitate the volatilization of organic pollutants (e.g., solvents, gasoline) and their extraction to the soil surface. However, evaluating and modeling the flow and distribution of air is limited by the complicated physics of unstable multiphase flow. These complexities drive researchers to search for empirical relations and rules of thumb to design air-sparging systems. In this research, we use previously published experimental data to demonstrate the capabilities and discuss the limitations of the classical physical solutions of steady single-phase flow to evaluate air flow through wet porous media such as aquifers.