Author(s): Raksmey Na, Sang Deog PARK, Ho Kook Park

Linked Author(s): Sang Deog PARK

Keywords: Macro-porous media; Drag force; Reynolds number; High flow;

Abstract: The study of fluid flow through porous media is mostly taken place in number of technical areas including groundwater flows, flow through embankment dams, initiation of the channelized debris flow, filtering, and bio-fluid flow. Since, the valley type debris flow may occur when the river bed collapses due to the resistance of the steep river bed with the effect of the side slope and internal drag force acting on the bed. Hence, drag force and Reynolds number are the predominant factors to describe the behavior of flow in macro-porous media. Until now, the studies on the drag force have been mostly concerned with the drag coefficient of a certain shape, yet they have not reached the steep slope with large pore structure. Thus, the study of internal drag force of the high flow for the wide range in macro-porous media is of importance. In this study, drag force was experimentally investigated under the water flow through uniform macro-porous media. The three different sizes of spherical glass bead and medium length were selected. The 10-kg loadcell was used to measure the internal drag force of the macro-porous media. The experimental results show that on the wide range of velocity of the idealized macro-porous media is represented well by the Forchheimer’s equation. The grain size significantly affects drag force, while the flow distance slightly affects. This finding is useful and helpful to describe the behavior of drag force induced by water flow in heterogeneous (mixed spherical size particles) and natural (gravel or rock) macro-porous media.

DOI: https://doi.org/10.3850/38WC092019-1036

Year: 2019