Browsing by Author "Kim, Albert S."

Now showing 1 - 3 of 3
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    Coupled transport phenomena of a bioswale process during storm runoff events: a CFD study using OpenFOAM
    (Desalination Publications, 2019-02) Irvine, Joshua Lelemia; Kim, Albert S.
    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.
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    Hydraulic design perspectives of bioswale vegetation layers: a meta-research theory
    (Desalination Publications, 2019-03) Irvine, Joshua Lelemia; Kim, Albert S.
    Optimized bioswale-design requires a fundamental understanding of mass and momentum transfer through a bioswale vegetation layer (BVL) on top of the porous soil zone. Conventional theories of canopy flows are applicable to structuring BVL in a planning phase. Plants in the BVL can be modeled as an embedded collection of cylindrical rods characterized by using (mean) diameter and height. The number density and spatial periodicity of the plants determine the structural and hydraulic characteristics of the BVL. The current paper stands as what we are calling meta-research or “research of research” consisting of an in-depth literature review followed by our own theoretical development and its application. A design equation for an emergent BVL is developed, which suggests the minimum length-to-width ratio of a bioswale as a function of runoff hydraulic characteristics. We calculate a proper bioswale length near which the viscous force fully supersedes the inertial force along the BVL. Moreover, a supplementary graphical method is developed within this study as a simple tool with which to design bioswale dimensions.
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    Understanding bioswale as a small water and wastewater treatment plant: A theoretical review
    (Desalination and Water Treatment, 2018-12) Irvine, Joshua Lelemia; Kim, Albert S.
    Stormwater threats can be mitigated with the application of sustainable and renewable technologies such as low-impact development (LID) and best management practice (BMP). This paper aims to fill the present gap in practical applications and engineering science regarding modeling bioswales, a type of LID/BMP devices. Included is a new theoretical framework that treats bioswales as combined physico-chemical processes. A discussion of a coherent analogy between the bioswale and a conventional water and wastewater treatment plant (WWWTP) is presented without including biological processes. Finally, we provide new perspectives regarding computational fluid dynamics (CFD) for widespread use as a promising tool to optimize LID/BMP design for stormwater management.