Simulación numérica del tiempo de escape en un vórtice tridimensional y de la sedimentación en vórtices bidimensionales periódicos para partículas pesadas

Abstract

In this Ph D. Thesis we have investigated two fluid dynamics problems in which appear interaction between heavy particles and fluids, with the aim of improving the understanding of the turbulent regime. First, it is analyzed the time that small heavy particles take to escape from a three-dimensional vortex. It has been determined by numerical simulation and then it is developed a theoretical formulation for that escape time. Secondly, it is analyzed the settling of particles in the presence of a fluid field that has not been considered until now, involving a two-dimensional arrangement of vortices periodically repeated. It has been found that the particles accumulate in areas of preferential settling (allowing their separation and classification) and that their average settling velocity increases in comparison with that in still flow.