Mechanisms and upscaling of dispersion in porous media from the pore to the Darcy scale
Jueves 5 de Marzo a las 12:15 h
Departamento de Ingeniería Civil y Ambiental, Modulo D2-Aula CIHS, Planta Baja
We show that finite P éclet transport can be predicted from the Eulerian velocity distribution of the medium, which is a flow property, together with the correlation distance and tortuosity of the sample, which are geometrical properties. The main assumption is that the medium is made of a network of
tubes that all exhibit a Poiseuille velocity profile. This allows for the derivation of the distribution of mean velocities in the domain from the Eulerian velocity distribution. This distribution is the main input to our model since it contains the true statistics that particles experience. It is due to the di ffusion process that forces particles to sample the full velocity profile over a throat. Predictions from the model are validated against direct particle tracking simulation on real digitized samples for a wide range of P éclet regimes.