A micromodel experiment provides direct visualization of dynamic fluid flow within a porous network, and may be used to identify fluid distribution within single pores, flow parameters and fluid-fluid interactions. This information may be utilized to numerically predict fluid flow at different length scales.
Micromodels are suitable for experimental study of flow in porous media at the pore scale, the smallest scale relevant to petroleum recovery. Micromodels contain enclosed pore networks where flow can be observed visually in a microscope, making it possible to study how pore scale events affect flow patterns and displacement efficiency at larger scales. Visual studies enable several key features regarding oil recovery to be identified and described, and the effect of changing parameters like injection rate and types of injection fluids can be observed. Both naturally occurring displacement processes, such as imbibition and drainage of water, and EOR processes, such as CO2 gas or CO2 foam injection amongst many, can be studied by the use of micromodels.
Micromodels consist of a digitally constructed pore network etched into a material and enclosed by a transparent surface, which typically is glass or plastic. The pore network can be constructed manually after a desired design, or it can be constructed from 2D thin-sections of real porous rocks to represent a realistic pore structure. The first method is normally preferred when elementary study of flow physics with controlled flow conditions is the objective, while the second method is used to study fluid flow in real porous rocks. Micromodels can obtain a range of values concerning porosity, permeability, wettability, pore and grain sizes and shapes, grain surface roughness, pore network size and coordination number, the average number of flow entrance/exit paths from pores in the network.