Analysis of non-Brownian particle deposition from turbulent liquid-flow

International audienceThe deposition of non-Brownian particles from turbulent liquid-flow onto channel walls is numerically analyzed. Theapproach combines Lagrangian particle tracking with a kinematic model of the near-wall shear layer. For nonbuoyantparticles, direct interception is the main deposition mechanism and the deposition velocity scales as the particle diameter(in wall units) to the power of 1.7. When wall/particle hydrodynamic interactions are taken into account, the depositionvelocity is significantly reduced and the correction factor scales as the cubic root of the wall roughness to particlediameter ratio. For buoyant particles, sedimentation is usually the predominant deposition mechanism and the hydrodynamicinteractions significantly affect the deposition velocity when the drainage characteristic time driven by buoyancyis of the order of the particle residence time close to the wall. Last, a wall-function for the suspended particles is proposed