Lagrangian Simulation of Particle Dispersion

Eulerian and Lagrangian approaches have been studied at Rouen for the prediction of particle dispersion in turbulent flows. A first computer code DISCO (Dispersion computing) has been developed during the past Years for predicting turbulence and the dispersion of discrete particles in the framework of an Eulerian approach. In that method, the particles are considered as a continuum and satisfy a transport equation which involves a dispersion tensor linked to particles and fluid characteristics. The Tchen theory (on discrete particle displacement) and the Batchelor theory (for diffusion of fluid particles) are used to determine the dispersion tensor, and a correction factor is defined to take into account for the crossing trajectories effects.