(122f) Numerical Simulations of Flow Patterns in a Moving Granular Filter Bed with an Asymmetric Louvered-Wall and Obstacles

This study numerically investigated the flow patterns in an asymmetric louvered-wall moving granular filter bed with a wedge-shaped obstacle placed at each stage of the granular filter bed. Extending the DEM model of FILTER-2D by Chou et al. [5-6], a three-dimensional model based on discrete element method, FILTER-3D, was developed and employed to analyze the flow patterns in a moving granular filter bed, and the effect of a wedge-shaped obstacle on the stagnant zone adjacent to louvered-wall. The numerical predictions qualitatively agree with the experimental results by Chou et al. [9]. The method to determine the placement of a wedge-shaped obstacle in an asymmetric louvered-wall moving granular filter bed presented by Chou et al. [9] was slightly revised by using the conditions, and , to obtain a better wedge-shaped insert. Therefore, not only the quasi-stagnant zone adjacent to the louvered-wall in the granular filter bed can be shrunken, but also the efficiency of filtration can be improved due to the fact the slower particle velocity causes more inertial impaction between granular filtration media and the fine dust. KEYWORDS: DEM, Moving Granular Filter Bed, Asymmetric Louvered-Wall, Obstacle.