Spray impingement on a wall in the context of the upper airways

We here address the modelling of an aerosol hitting the walls of the airways or an endotracheal tube used for a mechanical ventilation, and the possible creation of secondary droplets that may follow. We present a kinetic modelling of the spray-wall interaction and propose a boundary term that takes into account the possible formation of secondary droplets. Next we answer the following question: when, modelling the delivery of solute therapeutic aerosols, is it necessary to take into account the apparition of secondary droplets? A study of empirical models of drop-wall interaction allows us to conclude that in usual respiratory conditions, no secondary droplets appear. Finally, we perform numerical simulations of an aerosol delivered in an endotracheal tube, in the mechanical ventilation case. The idea is to compare our numerical results to in silico experiments from aerosols specialists. We study the trajectories and the deposition locations of spray droplets.