Direct Numerical Simulation of Particle Interaction with Coherent Structures in a Turbulent Channel Flow

The interaction of small, solid particles with turbulent coherent structures near the walls of a vertical channel is numerically investigated using direct numerical simulation (DNS) together with Lagrangian particle tracking (LPT) and a point-force approximation for the feedback effect of the particles on the fluid. Results from conditional sampling show that the diameter and the streamwise extent of the mean vortices are increased due to the momentum exchange between the two phases, depending on the particle inertia, gravitational settling and interparticle collisions.