Étude de l'interaction entre un fluide et des particules en suspension dans les écoulements sous l'action de la pesanteur et les courants de densité

In arid regions wind storms and flood flows carry in suspension sand or particles plucked from the soil. On the other hand irrigation and draining channels must have a special design in order to avoid erosion and the subsequent transportation of sediments. It is of importance in order to explain these phenomena to study the hydrodynamical interaction between the fluid phase and the suspensed particles and this is the principal purpose of this paper. Density currents are examples or two-phase flow, the suspensed material acting as a determining factor. They are particularly discussed as they give a remarkable illustration of the interaction between solids and liquids and play moreover an important part in the study of reservoirs formed by dams in arid regions. This memoir analyses too the similarity between sand or dust storms and density currents.