Coupled transport phenomena of a bioswale process during storm runoff events: a CFD study using OpenFOAM

Abstract

Coupled transport phenomena within a bioswale are studied using the open-source computational fluid dynamics (CFD) software OpenFOAM. We investigated the unsteady behavior of momentum and mass transfer in a double-layered bioswale. To study the diffusive transport of a model pollutant, we developed a new solver, that we named interPhaseDiffusionFoam (https://github.com/enphysoft/ interPhaseDiffusionFoam), which better mimics transport phenomena of non-volatile species at a phase boundary. We observed that heterogeneous infiltration patterns are strongly dependent upon stormwater runoff velocity, reverse air flow, and the presence of the drain pipe. The performance estimation and optimal design of a bioswale were thoroughly examined using 2D CFD simulations for a holistic understanding of coupled mass and momentum transport phenomena.