Hydrodynamic loading of a porous plate at low Reynolds number conditions

Abstract

In this thesis, we discuss our experimental work conducted to investigate the flow through and around porous disks driven through a viscous fluid at low Reynolds number conditions. Specifically, we present the results from a series of experiments in which we investigated the hydrodynamic drag experienced by thin (thickness to diameter ratio is t/d < 5%), circular disks of constant porosity (void fraction, [phi] = 69±2%). We characterize the dependence of the hydrodynamic loading on the size and shape of the perforations in the disk using a parameter called drag ratio, which compares the magnitudes of drag that porous and impermeable disks experienced. These experiments were conducted using a displacement controlled experimental apparatus, which, to the best of our knowledge, is the first of its kind. We benchmarked this experimental apparatus with a second experiment, and we found excellent agreement between experimental results and the analytical prediction. We find that the drag ratio depends on the effective void radius, but not on the thickness of the disks. We rationalize our results by comparing them to an existing analytical solution by way of a scaling analysis.