The interaction between a turbulent carrier flow and suspended solid particles can lead to a number of coupling effects which are most prominently manifested by the following quantities: (a) inhomogeneous spatial distribution of the solid phase, (b) modified particle settling velocity, (c) modulation of the turbulent flow field. All three of the above phenomena are of considerable scientific interest. For instance, a particle distribution which exhibits significant spatial structure will in general lead to collision frequencies which are non-trivial to predict. In this project we are simulating the fluid flow and the particle motion in triply-periodic domains with and without a priori "background turbulence". Special emphasis is focused on a very high resolution of the near-field around particles as well as a sufficiently large computational domain size. The volume fraction is chosen in the dilute regime.

Chouippe, A. and Uhlmann, M. (2015) Forcing homogeneous turbulence in DNS of particulate flow with interface resolution and gravity. *Phys. Fluids*, 27(12):123301 [DOI]

Uhlmann, M. and Doychev, T. (2014) Sedimentation of a dilute suspension of rigid spheres at intermediate Galileo numbers: the effect of clustering upon the particle motion, *J. Fluid Mech., *752:310-348, [DOI]

Uhlmann M. and Dušek J. (2014) The motion of a single heavy sphere in ambient fluid: a benchmark for interface-resolved particulate flow simulations with significant relative velocities. *Int. J. Multiphase Flow*, 59:221-243, [DOI]