Simulation of a dust lifting process with rough walls

Abstract

The aim of this paper is to present results of Eulerian-Lagrangian simulations of the dust lifting behind a shock wave in a two-dimensional domain with rough walls. Since interparticle and particle-wall collisions are important for the development of the process, simulating walls with a certain roughness is of interest influencing the trajectories of the near-wall particles, which then exchange momentum with particles higher up on the layer. Results of the simulations are shown as snapshots of particle positions at certain points in time. Comparisons between simulations with smooth walls and rough walls with varying initial dust layer thicknesses and number of particles are presented. Statistical data from the simulations are compared, such as average particle height and the number of particle-particle collisions, as is the mechanical energy lost in collisions. For the rough wall simulations, statistics relating the inclination of the virtual-wall with the emergent vertical velocity of particles and the energy lost in collisions are shown for different Gaussian distributions of angles. It was found that the general lifting effect is more intense in the rough wall simulations, the difference increasing with layer thickness. The statistical and energy data also showed significant differences between the smooth and rough wall simulations. The trends seen are substantiated by presenting some results of