Multiphysics Computational Fluid-Dynamics (CFD) Modeling of Annular Photocatalytic Reactors by the Discrete Ordinates Method (DOM) and the Six-Flux Model (SFM) and Evaluation of the Contaminant Intrinsic Kinetics Constants

Computational Fluid Dynamics (CFD) was used to model an annular photocatalytic reactor by solving the Radiative Transfer Equation (RTE) using Discrete Ordinates Model (DOM) and Six-Flux (SFM) with isotropic scattering. The RTE boundary condition (BC) at light entrance wall SFM either irradiance or fluence rate, calculated LSSE, LSDE ESDE emission models. Total Rate of Photon Absorption (TRPA) rate BC overestimated 29 - 21 % in comparison DOM, when optical thickness varied between 1.8 3.2 %, underestimated 3.1–8.8 BC. intrinsic reaction kinetics constants 2-hydroxybenzoic acid (2-HBA) determined experimental reactors operated very high thicknesses were 1 higher 18 lower, than respectively, as Overall, combined provides a more accurate evaluation LVRPA constants, instantaneous solutions, while DOM computational time > 20 min. This aspect is highly important solar fluctuating irradiance.