Analysis of inertial particle drift dispersion by direct numerical simulation of two-phase wall-bounded turbulent flows

This paper analyzes inertial particle drift dispersion based on the numerical database established by direct numerical simulation of a dilute particle-laden two-phase turbulent channel flow, in which the released particles are tracked by a Lagrangian trajectory method. Low-inertia particles tend to travel toward the walls at negative velocities. High-inertia particles however display very low drift in the near-wall regions. Effects of particle size and material density on particle drifts are also jointly studied. The statistical results show that particles drift dispersion depends significantly on particle Stokes number. Low-inertia particle drift dispersion causes a direct low-inertia particle deposition on the wall, and hence increases the particle concentration close to the walls. The results are valuable for understanding the mechanisms of particle dispersion by turbulence.