Viscous Flow in Multiparticle Systems at Intermediate Reynolds Numbers

Abstract

<p> This dissertation describes an extention of fluid mechanical data for flow around blunt objects in the intermediate Reynolds Number regime using the digital computer. The aim was to develop fluid mechanical models to predict the flow phenomena around a blunt object in an infinite fluid and a multiparticle system. </p> <p> The dissertation is divided into two self-contained parts. Part I describes the flow around a blunt object in an infinite fluid media. The flow around a solid sphere in steady flow, a solid sphere in accelerating flow and a spherical liquid drop in steady flow are described. The study demonstrates that the actual drag becomes asymptotic with the Oseen drag relation as the Reynold Number approaches zero. Secondly, the study demonstrates that acceleration from rest of a sphere under the influence of gravity can be predicted precisely by solving the fluid mechanical equations. Finally the flow in and around a circulating spherical raindrop is presented. </p> <p> Part II describes the extension of the cell model for multiparticle systems in the creeping flow regime to the intermediate Reynolds Number regime. Three cases were studied: beds of solid spheres, cylinder bundles in cross-flow and gas bubble swarms. Theoretical predictions of pressure drop through the assemblage and material or heat transport were obtained. Comparison of these predictions with experimental data has shown that the approach provides an excel lent first approximation for predicting multiparticle phenomena. </p>