Hydrodynamic drag force exerted on a highly porous sphere moving towards an impermeable plate
Journal
Chemical Engineering Science
Journal Volume
53
Journal Issue
20
Pages
3571-3578
Date Issued
1998
Author(s)
Wu R.M.
Abstract
This study numerically evaluates the hydrodynamic drag force exerted on a porous sphere moving through a Newtonian fluid towards an impermeable flat plate at a Reynolds number ranging from 0.1 to 40. The sphere is assumed to be highly porous, whose interior flow field is modeled by the combined Darcy-Brinkman model. The surrounding fluid flow field is governed by steady-state Navier-Stokes equations. When the floc permeability is rather high, which is common for sludge flocs, no boundary layer separation occurs in the after-sphere region at large Reynolds numbers. The drag force thereby adheres to a Stokes' law like relationship.This study numerically evaluates the hydrodynamic drag force exerted on a porous sphere moving through a Newtonian fluid towards an impermeable flat plate at a Reynolds number ranging from 0.1 to 40. The sphere is assumed to be highly porous, whose interior flow field is modeled by the combined Darcy-Brinkman model. The surrounding fluid flow field is governed by steady-state Navier-Stokes equations. When the floc permeability is rather high, which is common for sludge flocs, no boundary layer separation occurs in the after-sphere region at large Reynolds numbers. The drag force thereby adheres to a Stokes' law like relationship.
Subjects
Drag
Numerical
Plate
Porous
Type
journal article