A Numerical Assessment of the Efficacy of a Topography Design with Increasing Gradient Complexity for Filtering Biofouling Material through the Membrane Module of a Water Treatment System

Biofouling can also be defined as the micro- / macro- organisms stuck on the surface that has been submerged in water. This is normally found in marine industry and water treatment industry. There are 3 ways of antifouling where the 3rd method surface modification was the main point to be focused on. Surface modification has high potential for antifouling performance and is not harmful to the ecosystem. In this research study was to find out the efficacy of antifouling performance with increasing the gradient complexity. The 2 models used were smooth topography and circular topography and have been manipulated and simulated with WorkBench 2020, Computational Fluid Dynamic (CFD). The results were simulated with the correct meshed and models. The simulated results were converged and 2 hydrodynamic variables; velocity and wall shear were used to check the efficacy of antifouling performance.

Investigation of carbon dioxide photoreduction process in a laboratory-scale photoreactor by computational fluid dynamic and reaction kinetic modeling

The production of solar fuels via the photoreduction of carbon dioxide to methane by titanium oxide is a promising process to control greenhouse gas emissions and provide alternative renewable fuels. Although several reaction mechanisms have been proposed, the detailed steps are still ambiguous, and the limiting factors are not well defined. To improve our understanding of the mechanisms of carbon dioxide photoreduction, a multi-physics model was developed using COMSOL. The novelty of this work is the computational fluid dynamic model combined with the novel carbon dioxide photoreduction intrinsic reaction kinetic model, which was built based on three-steps, namely gas adsorption, surface reactions and desorption, while the ultraviolet light intensity distribution was simulated by the Gaussian distribution model and Beer-Lambert model. The carbon dioxide photoreduction process conducted in a laboratory-scale reactor under different carbon dioxide and water moisture partial pressures was then modeled based on the intrinsic kinetic model. It was found that the simulation results for methane, carbon monoxide and hydrogen yield match the experiments in the concentration range of 10−4 mol·m−3 at the low carbon dioxide and water moisture partial pressure. Finally, the factors of adsorption site concentration, adsorption equilibrium constant, ultraviolet light intensity and temperature were evaluated.