Numerical modeling of miscible displacements in permeable media monitored by imaging techniques

Laboratory corefloods are widely used to study the theoretical aspects of fluid flow in permeable media and to obtain their petrophysical properties. An effective approach to analyzing laboratory displacements is to combine flow imaging with numerical simulation of the flow. The injected fluid concentration or saturation imaged during a displacement can be compared with the simulated concentration or saturation. The medium's petrophysical properties can then be calculated from a history-matching process in which these properties are the matching parameters.;The objective of this dissertation was to develop a systematic procedure to characterize a porous medium used in a displacement experiment and to interpret the displacement results. The procedure developed combined rock and fluid flow imaging with geostatistical simulation and three-dimensional numerical flow simulation to determine the petrophysical properties of the medium, to identify the flow patterns obtained during the displacement, and to identify the forces and other factors, such as the medium's heterogeneity and the experimental boundary conditions, that led to those patterns.;A powerful, three-dimensional chemical flooding simulator was adapted to simulate first-contact miscible flow at the core scale. Artificial permeability fields representative of the cores being tested were constructed by stochastic simulation based on quantitative and qualitative images of the cores and used as input data for the simulator. A comprehensive data set of first-contact miscible displacements, imaged by X-ray Computed Tomography and Nuclear Magnetic Resonance, was history matched by high-resolution numerical simulation.;Results show that the combination of three-dimensional numerical simulation with imaging of laboratory displacements is an effective tool for obtaining accurate petrophysical properties of permeable medium samples. This approach is superior to the traditional methods because it takes into account gravitational effects and the sample's heterogeneity. Furthermore, it enables the assessment of the roles of the flow driving forces, the permeable medium's heterogeneity and the inlet boundary condition in determining the flow patterns obtained in the displacement.;The experience gained from this and other studies was used to develop a systematic and novel procedure to interpret the results of displacement experiments based on the combination of imaging, geostatistical simulation and three-dimensional flow simulation.