Percolation Simulation Of Porous Media Based On Lattice Boltzmann Method

Porous medium is widely exists in the oil field,and it's one of the core content of petro-leum engineering.With the development and innovation of the computer technology,numerical simulation method has developed as an important method as experimentation method and analysis method.As the complex structure of the porous medium,it's difficulty for the traditional numerical simulation method like finite element method,finite difference method,finite volume method to deal with or program realization.As a mesoscopic method,lattice Boltzmann can overcome the problems above preferably,as well it offers a new thinking to solve the flow problem in porous medium.On account of characteristics above,lattice Boltzmann method is applied to simulate the flow in the porous medium in this paper to enhance the understanding of this problem.This thesis focus on the following main points:1.The basic thought and models,introduce the basic thought of the lattice Boltzmann method and the specific forms of it,' uses Chapman-Enskog expansion recovers to the macro-scopic equations,drawing off the basic flow path of the lattice Boltzmann method.2.Boundary treatments of the lattice Boltzmann method,respectively introduces the scheme like heuristic scheme,kinetic scheme or extrapolation scheme.Applied the boundary in the basic models to simulate several kinds of classical flows.3.Image processing of the porous medium,a new way to confirm the threshold value of the porous medium image based on macro parameter is applied here.Median filtering is used here to remove the isolated noise points,then we can achieve the image of the core for the numerical simulation.4.Simulation of seepage flow in the porous medium,introducing the transformation between physics unit and lattice unit.And conduct the lattice Boltzmann method simulation based on the image achieved before.Flow field in the porous medium is given and perme-ability is forecasted.