THEORETICAL-ANALYSIS OF MISCIBLE DISPLACEMENT IN FRACTURED POROUS-MEDIA BY A ONE-DIMENSIONAL MODEL .1. THEORY

A one-dimensional model is formulated to describe miscible displacemen t in fractured porous media. Four parameters, R1 (normalized fracture capacity), B (productivity capacity ratio), M (viscosity ratio), and N (gr) (gravity number) that characterize the process are identified. No -crossflow and crossflow equilibrium assumptions are made, and solutio n methods for both cases are provided. In the case of crossflow equili brium, the flow is balanced by the viscous and gravity forces. Three b ranches of solution characteristics are discovered. These are: 1) domi nant viscous crossflow, 2) moderate gravity crossflow, and 3) strong g ravity crossflow. The criterion for each case is given in terms of vis cosity ratio and gravity number. Depending on the magnitude of viscosi ty ratio and gravity number, crossflow direction changes along the len gth of matrix-fracture interface.