Computer Simulation of Concentrated Fluid-Particle Suspension Flows in Axisymmetric Geometries

Article type: Research Article

Authors: Hofer, Michael^{; *} | Perktold, Karl

Affiliations: Institute of Mathematics, Technical University of Graz, Graz, Austria

Note: [*] Reprint requests to: Michael Hofer, Institute of Mathematics, Technical University of Graz, Steyrergasse 30/3, A-801O Graz, Austria; Fax: +43 316 873 8621; E-mail: hofer@matd.tu-graz.ac.at

Abstract: To investigate the particle migration effects and fluid-particle interaction occurring in the flow of highly concentrated fluid-particle suspensions, a numerical method has been developed for effective computer simulation in arbitrary axisymmetric geometries. In the mathematical flow model the suspension is treated as a generalized Newtonian fluid where the effective flow properties of the suspension (density and viscosity) are determined by the local volume fraction of the particles. The description of the particle motion is governed by a modified transport equation with diffusion coefficients accounting for the effects of shear-induced particle migrations. The strongly coupled system of flow and transport equations is solved by applying the Galerkin finite element method and a velocity-pressure projection scheme. The numerical results in tube flow demonstrate strong particle migration towards the center of the tube and an increasing blunting of the velocity profiles which is in good agreement with an available analytical solution. In the case of flow through a stenosed tube model, particle concentration is lowest at the site of maximum constriction whereas a strong accumulation of particles can be seen in the recirculation zone downstream of the stenosis.

Keywords: Fluid-particle suspension, computer simulation, lateral particle migration, concentrated systems

DOI: 10.3233/BIR-1997-344-502

Journal: Biorheology, vol. 34, no. 4-5, pp. 261-279, 1997