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A Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Petroleum Systems Engineering, University of Regina. xix, 296 p. Fluids flow in porous media are usually affected by multiphysics domains. Thermal, mass transfer, and hydraulic domain will all significantly affect the features of fluids flow in porous media. Thermal fluids coupling problems occur almost in every area of reservoir engineering such as geothermal energy development, and heavy oil recovery. Mass transfer is another important mechanism that should be considered in solvent based heavy oil recovery and unconventional enhance oil recovery methods. This research focuses on using analytical source and sink function method applied in heat transfer and mass transfer to simulate two domain coupling model. Based on thermal source and sink function derived in this thesis, convective heat is treated as a simple special form of source and sink function. The calculation of transient convective heat amount in Laplace domain problem has also been solved innovatively in this dissertation. Sensitivity analysis on segment size from computing prospect, thermal diffusivity and velocity from system prospect are analyzed to help understand the heat transfer process integrating conduction and convection mechanism. Secondly, this convective source function methodology is applied in a 2D model of geothermal energy recovery process. A typical geothermal energy recovery well pair is simulated by the innovative coupling methodology. Different well pair locations and fractured wells are examined through this model referring to the enhanced geothermal system technology for hot dry rock reservoir. Big jumps from heat transfer to mass transfer are made to analytically model the solvent injection process for heavy oil recovery. Multi-mechanisms including diffusion and dispersion, viscosity reduction, oil swelling are considered analytically and integrated into the two domain coupling model. Solvent-based Post Cold Heavy Oil Production with Sand (CHOPS) with single fracture structure is also modeled by this methodology. The mass transfer proves to have significant influence on fluids flow in porous media. Heavy oil thermal based recovery methods such as SAGD have complicated interactions phenomenon between thermal domain and pressure domain. Viscosity reduction, fluids thermal expansion and heat loss to caprock will significantly affect the operation energy efficient and environment footprint. Sensitivity analysis of key parameters affecting the thermal injection process are also conducted. Student yes

A Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Petroleum Systems Engineering, University of Regina. xv, 95 p. Enormous heavy oil resources has been found in western Canada. But some factors especially high viscosity limit their development. Thermal recovery methods which injecting heat into the reservoir or in-situ combustion, have been widely used to enhance heavy oil recovery. The viscosity of the crude oil has been lowered by raising the temperature of the reservoir, so temperature and pressure profiles are important factors for making operations and development plans in thermal recovery process. Understanding how heat transfer influences the fluids flow is the key knowledge for us to make the right decisions. In this study, a novel heat transfer model in radial system, integrating both conduction and convection, has been developed to describe the heat transfer in the heating reservoir. In this temperature domain model, heat injection rate keeps constant and dimensionless variables are defined to reduce the model to the dimensionless form. Variable transformation and Laplace transformation are performed to derive the analytical solution in Laplace space. By using Stehfest inverse algorithm, the solution in Laplace space can be converted to dimensionless analytical solution in real time space. With an analytical solution of temperature domain, fluid flow in the reservoir can be generated by dividing the whole reservoir into numbers of sub-sections. Pseudo-time is introduced to solve the changing viscosity and makes the analytical model can be solved. Dimensionless variables are also defined and the pressure are solved in Laplace space. Sequentially coupling method is applied to use the temperature profiles in pressure domain. The final dimensionless analytical solutions are obtained by Stehfest inverse algorithm. Numerical simulations by COMSOL Multiphysics are conducted to validate the analytical solutions of the models. Satisfactory agreements of the results are achieved between analytical solutions and numerical simulation results. Sensitivity analysis are also conducted to analyze the influence factors of heat transfer and fluid flow. Heat injection rate, heat capacity of fluids and rock, permeability are important parameters for heat Student yes