Lattice-Boltzmann simulations of particle transport in a turbulent channel flow

•Effect of St on particle concentration profiles in a turbulent flow is studied.•Particles with low St exhibit a high concentration near the wall.•Particles with high St exhibit a high concentration near the center.•Impact of turbophoresis on preferential particle motion is discussed. The lattice-Boltzmann Method (LBM) is employed to directly simulate the transport of particles approximated as ’point particles’ in a turbulent channel flow. Prior experimental studies have shown that particles preferentially move toward the wall or center in a pipe flow depending on their Stokes number (St). The simulations are carried out for a range of St and they reproduce the observed experimental behavior. Since the only effect that can influence the transport in the cross-flow direction is turbulence in the context of the simulation framework adopted here, it is concluded that turbophoresis is responsible for the behavior.