Simulation and Porous Media Characterization Using the Lattice Boltzmann Method
Speaker:Professor Antonio C. M. Sousa
Department of Mechanical Engineering
University of News Brunswick, Fredericton, NB, Canada
Date & Time:23 Aug 2007 (Thursday) 16:30
Venue:L105

Abstract

The Lattice Boltzmann Method (LBM) is a particle based method for fluid flow simulations, in which the fluid density and velocity for each particle are calculated based on a distribution function, and its evolution at each time step is realized through a two-step process involving streaming and collision. Since the introduction of the LBM in 1988, this method has been applied to a wide spectrum of fluid flow and heat transfer problems that encompass, for instance, the modelling at mesoscopic level of single and multiphase flows, phase change, turbulence, and porous media. The present seminar has as its prime focus to present a few case studies dealing with LBM porous media fluid flow simulations at pore level. It will be also mentioned recent advances of a promising area of LBM simulation related to turbulence modelling with the Large Eddy Simulation. The choice of these two disparate fields is driven not only for their relevance, but primarily to demonstrate the flexibility and potential of the LBM as a universal numerical tool in Computational Fluid Dynamics. The first topic is of interest in a great number of applications; here the motivation is to improve the understanding of the Resin Transfer Moulding (RTM) process, which is widely used in the manufacturing of polymeric components. The simulation of fluid flow in porous medium at pore level is reported with particular emphasis on the prediction of the permeability and tortuosity of ordered and random media, and consequent parametric analysis. A challenging problem in the RTM process is the fluid flow at the open - porous medium interface. The macroscopic simulation of the porous medium, in general, fails to predict the actual slope and magnitude of the interfacial velocity; to overcome this shortcoming further modelling is required, and to this purpose different models have been proposed. The LBM, as will be shown, can predict the magnitude of the slip velocity and shear stress at the interface on both open and porous sides were predicted without resorting to any modelling.