"Diffusion of light by particles: modeling and applications to the characterization of multiphase flows" by Matthias Sentis
The Thursday, March 30, 2017
at 2:00 PM
room F021b,
Laboratoire Hubert Curien,
42000 Saint Etienne
Seminar by Matthias Sentis, postdoc at CEA Marcoule
Much progress has been made thanks to coherent optical techniques in the characterization of the dispersed phase of multiphase flows. The development of such techniques can be described in two main steps.
The first step is to solve the direct problem of dissemination of light by a particle system to predict the signal recorded by the acquisition system. Three examples of a diffusion model will be presented: a hybrid model coupling optical geometry and physical optics, a Monte-Carlo probabilistic model and a propagation model in astigmatic optical systems suitable for online digital holography.
The second step is to solve the inverse problem and to get the optical properties of the particulate medium from recorded optical signal. A first system of diffusion of multi-angle light based on emerging technology organic photodetectors will be described. The latter is adapted to the measurement of size of flowing particles in a constrained industrial environment. A second one, an on-line digital holography system enabling a simultaneous measurement of the size and the 3D position of the particles in a flow will be detailed. We shall see that it is also possible to measure the refractive index of these particles.
This seminar will be held in French.