Regensburg 2000 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

DY: Dynamik und Statistische Physik

DY 22: Granulare Materie I

DY 22.7: Talk

Tuesday, March 28, 2000, 12:30–12:45, H2

Particle Scale Simulations of Bidisperse Suspensions — •Kai Höfler and Stefan Schwarzer — Institut für Computeranwendungen I, Universität Stuttgart

The theoretical understanding of particle fluid mixtures is limited to the case of dilute suspensions where the hydrodynamical interactions can be reduced to pair interactions [1]. Even at moderate particle concentration of about 10% only phenomenological theories describe the experimental data.

Obtaining experimental data more detailed than e.g. the average particle velocities proves to be difficult [2] whereas numerical simulation on particle level are able to provide the means for detailed measurements.

This advantage is used to measure e.g. the evolution of volume fractions in bidisperse sedimentation in a viscous fluid (Re<0.5). We compare the results with the predictions of a kinematic model. The simulations have been performed using a recently developed simulation method which solves the Navier-Stokes equation on a fixed rectangular grid and resolves the fluid motion around the particles.

[1] G. Batchelor, J. Fluid Mech. 119, 379 (1982).

[2] H. Nicolai et al, Phys. Fluids 7, 12 (1995).