Miscible Displacement Porous Media: MOC Solution

Abstract

The method of characteristics (MOC) was revised to solve convective‐dispersion equations in a two‐dimensional, integrated saturated‐unsaturated porous medium. Instead of usual bilinear interpolation schemes, the revised procedure utilizes a three‐way linear interpolation scheme to assign seepage velocities to moving points in a two‐dimensional grid system. The coordinates and concentrations of moving points reintroduced into the two‐dimensional system are assigned using a random distribution. The accuracy of the numerical simulator was tested by comparison with available analytical solutions, numerical solutions and field data. Comparisons provided excellent agreement in almost all cases. Considering the nonhomogeneous field conditions encountered in the experimental plot, the simulated results are considered to be very good. The MOC eliminated numerical dispersion in simulation of miscible displacement in saturated, as well as unsaturated soils. A typical two‐dimensional drainage problem was solved in a nonhomogeneous, integrated saturated‐unsaturated porous media using the revised MOC.