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Abstract: A three‐dimensional numerical model was solved for a turbulent incompressible steady flow and the discrepancies and similarities between the software OpenFOAM® and ANSYS® Fluent on the flow modeling were analyzed. The evaluation was performed for the meshing, setup, and simulation step of the modeling process. Outcomes were contrasted with experimental data to validate the fluid flow obtained with both softwares. With this aim, an experimental pulse‐response technique was applied to obtain the residence time distribution (RTD) curve to be compared with the RTD curves achieved from the modeling. Additionally, images of the tracer transport in the experimental reactor were taken, showing good agreement with the computational fluid dynamics (CFD) predictions. [ABSTRACT FROM AUTHOR]

This work describes the procedure for the simulation of the operation of a photocatalytic reactor by using a multiphysics computational fluid dynamics (CFD) model based on the determination of the intrinsic kinetics parameters in an optically differential photoreactor. The model includes the rigorous description of the hydrodynamics, radiation transfer, mass transport and chemical reaction rate based on a mechanistic kinetic model. Possible existence of dead and recirculation zones has been identified from the flow field, showing a non-uniform flow through the reactor domain. The theoretical laminar profile is not reached due to the short length of the annular core and the departure from the ideal models has been quantified. The predicted velocity field has been experimentally validated with good agreement by injecting a tracer. The radiation field was simulated for slurry TiO 2 suspensions with concentrations between 0.005 and 5 g·L −1 , showing an optimum catalyst loading around 0.1–0.2 g·L −1 . Above this value, the increase in the absorption of radiation is negligible, whereas a more non-uniform radiation profile develops, keeping the most external regions of the reactor in the dark. The results of photocatalytic activity, using methanol oxidation as test reaction, showed good agreement between model predictions and experimental data, with errors between 2% and 10% depending on the catalyst concentration. The successful validation confirms not only the scientific background of the model, but also supports its applicability for engineering purposes in the design and optimization of large scale photocatalytic reactor to overcome some of limitations hindering the industrial development of this technology. [ABSTRACT FROM AUTHOR]