Doctor of Philosophy (PhD)
Civil and Environmental Engineering
Fluid flow in porous media is a subject of fundamental importance and relevant to numerous engineering applications. The comprehensive description of fluid interaction parameters containing wetting properties, fluid-fluid displacement ratio, and capillary pressure, are inevitably needed. Moreover, the fine-grained sediments’ response to various pore fluids and migration in porous media influences reservoir geomechanical properties and pore clogging is essential to a better understanding of fluids flow behavior.
This dissertation provides a detailed study of physical and geomechanical factors influencing fluids flow behavior in porous media. The two-dimensional micromodel tests have been conducted under a wide selection of fluids flow conditions. The experiments combined with pore network modeling are added to predict the fluid-fluid displacement ratio and capillary curves regarding different fluids. The fines’ geomechanical properties such as electrical sensitivity, compressibility, and hydraulic conductivity, together with pore plugging criteria are measured through various experiments including sedimentation, electrical sensitivity, and consolidation tests.
Results of this research show that increase in injection fluid velocity, viscosity, contact angle, and a decrease in fluid’s interfacial tension can result in higher viscosity and capillary numbers, which leads to an improvement of the fluid-fluid displacement ratio in porous media. Experiments with the subsequently conducted simulation corroborate a higher capillary pressure is expected with a decrease in contact angle and an increase in interfacial tension. Meanwhile, estimation of capillary pressure can be achieved with measured fluids’ wetting properties at different stress levels. Besides, the findings indicate that fine sediments’ geomechanical properties and clogging criteria can be altered due to fines’ response to distinct pore fluids. The geomechanical properties of the different fine sediments also vary with pore fluid chemistry changes. And, fines clogging in porous media is observed under conditions of a lower pore throat width/fine size ratio, a higher fine concentration, a relatively higher flow rate, and the changed pore fluids. Additionally, the presence of a moving gas/liquid meniscus increases the fines clogging potential. In summary, an understanding of fluids’ physical and geomechanical properties, in addition to an identification of fines influences, can help to evaluate the performance of fluids flow in porous media.
Cao, Shuang, "Microfluidic Pore Model Study on Physical and Geomechanical Factors Influencing Fluid Flow Behavior in Porous Media" (2017). LSU Doctoral Dissertations. 4187.