MESURES LAGRANGIENNES DE GOUTTES ÉVAPORANTES DANS UNE TURBULENCE HOMOGÈNE ISOTROPE PAR HOLOGRAPHIE NUMÉRIQUE

International audienceWe present an optical technique capable of measuring 3D trajectories and size evolution of a dilute flow of droplets dispersing in a high Reynolds number turbulence, from a Lagrangian point of view. The technique used is an in-line digital holographic set-up, with an original reconstruction algorithm based on an inverse-problem approach. The experiment has been performed with water and freon droplets in a locally well defined homogeneous, nearly isotropic, turbulence. This technique allows to visualise the thermal wakes behind the droplets which are tracked