Preferential concentrations of impurities in turbulent suspensions

Jérémie Bec, Observatoire de la Côte d'Azur, Nice, France

Dust, droplets and other finite-size impurities suspended in incompressible turbulent flows are commonly encountered in many natural phenomena and industrial processes. The most salient feature of such suspensions is the presence of strong inhomogeneities in the spatial distribution of particles. This phenomenon, dubbed preferential concentration, can affect the probability to find particles close to each other and thus have influence on their possibility to collide or to have biological, chemical and gravitational interactions. The aim of this lecture is to present an overview of the recent developments made in the statistical characterization of such preferential concentrations.