CFD Study of the Normal Force Exerted on a Sphere Moving Close to a Surface

International Journal of Chemical Engineering Research

© 2016 by SSRG - IJCER Journal

Volume 3 Issue 1

Year of Publication : 2016

Authors : Asem AL Jarrah

10.14445/23945370/IJCER-V3I1P101

How to Cite?

Asem AL Jarrah, "CFD Study of the Normal Force Exerted on a Sphere Moving Close to a Surface," SSRG International Journal of Chemical Engineering Research, vol. 3,  no. 1, pp. 1-6, 2016. Crossref, https://doi.org/10.14445/23945370/IJCER-V3I1P101

Abstract:

The normal force exerted on a sphere moving close to a surface, or what so called the wall-force, is an important force in modeling multiphase flow as well as in understanding the hydrodynamic behavior of moving an object close to a surface. The current widely spread models for thewall-force are based on derivations that relayon the potential flow theory, which ignore the effect of viscosity. Moreover, these current models always represent the wall face as a repulsive force, which is not the case as this study shows. In this study the wall-force was studiedusing Fluent Software Package and a relatively simple CFD-based correlation for the wall force was developed. The study shows that the wall force decrease rapidly as the distance of the sphere from the surface increases reaching zero at a distance of about half the diameter of the sphere then this force becomes weekly negative, attractive rather than repulsive, as the distance increases further. The wall force remains attractive untilapproximately the distance reachesfourtimes the diameter of the sphere and then becomes and remainszero as the distance increase further.

Keywords:

Wall Force, Normal Force, Sphere, Fluent Software Package, CFD.

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