Influence of vortex structures and turbulence on the carbon nanoparticles dispersion

This report aims to make a state the nanoparticles resulting from transportation systems lead to degradation of air quality causing damage to human health. The dynamics of these ultrafine particles is strongly related to the flow characteristics. The present work is devoted to numerical simulation of the two phase flow (air + nanoparticles) which develops downstream of a circular cylinder of a diameter d=2. 5cm. The goal is to provide a better understanding of the influence of turbulence and vortex structures created in the wake of a cylinder on the dispersion of the carbon nanoparticles. The studied flow (Re = 9300) was solved with the URANS model coupled with a lagrangian particle tracking. On the one hand, the results show that the nanoparticles tend to be located in the street of the vortices created by the wake of the cylinder. On the other hand, it is shown that the turbulence allows a wider dispersion compared to the case where no turbulence was considered.