The electrophysical property of saturated rocks is very important for reservoir identification and evaluation. In this paper, the lattice Boltzmann method （LBM） was used to study the electrophysical property of rock...The electrophysical property of saturated rocks is very important for reservoir identification and evaluation. In this paper, the lattice Boltzmann method （LBM） was used to study the electrophysical property of rock saturated with fluid because of its advantages over conventional numerical approaches in handling complex pore geometry and boundary conditions. The digital core model was constructed through the accumulation of matrix grains based on their radius distribution obtained by the measurements of core samples. The flow of electrical current through the core model saturated with oil and water was simulated on the mesoscopic scale to reveal the non-Archie relationship between resistivity index and water saturation （I-Sw）. The results from LBM simulation and laboratory measurements demonstrated that the I-Sw relation in the range of low water saturation was generally not a straight line in the log-log coordinates as described by the Archie equation. We thus developed a new equation based on numerical simulation and physical experiments. This new equation was used to fit the data from laboratory core measurements and previously published data. Determination of fluid saturation and reservoir evaluation could be significantly improved by using the new equation.展开更多
The Lattice Gas Automation （LGA） method, which is improved by introducing a reflection coefficient for the border between phases to show its effect on current path, is used in this paper to simulate the current flow...The Lattice Gas Automation （LGA） method, which is improved by introducing a reflection coefficient for the border between phases to show its effect on current path, is used in this paper to simulate the current flow in digital rock for investigating the effects of clay content and clay distribution types on the relationship between formation factor（F） and rock porosity（φ）. The digital rock model is constructed by simulating a natural deposit of matrix particles with different shapes and radius. Based on the simulation results, it was found that both dispersed clay and laminated clay can lead to a non-Archie relationship of F-φ. The non-Archie effect of laminated clay on the F-φ relationship was more significant than that of dispersed clay. Moreover, a realistic model is developed in this work for quantitatively describing the effect of clay content （Denoted as Vsh） on parameters a and m. These study results have further demonstrated the validity of LGA in study of electrical transport properties at a pore scale.展开更多
基金sponsored by the project No.50404001 from the National Natural Science Foundation of Chinathe National Key Fundamental Research & Development Project(Grant No.2007CB209601)+1 种基金the China National PetroleumCorporation Fundamental Research Program (Grant No.06A30102)the China Postdoctoral Science Foundation(Project No.2004035350)
文摘The electrophysical property of saturated rocks is very important for reservoir identification and evaluation. In this paper, the lattice Boltzmann method （LBM） was used to study the electrophysical property of rock saturated with fluid because of its advantages over conventional numerical approaches in handling complex pore geometry and boundary conditions. The digital core model was constructed through the accumulation of matrix grains based on their radius distribution obtained by the measurements of core samples. The flow of electrical current through the core model saturated with oil and water was simulated on the mesoscopic scale to reveal the non-Archie relationship between resistivity index and water saturation （I-Sw）. The results from LBM simulation and laboratory measurements demonstrated that the I-Sw relation in the range of low water saturation was generally not a straight line in the log-log coordinates as described by the Archie equation. We thus developed a new equation based on numerical simulation and physical experiments. This new equation was used to fit the data from laboratory core measurements and previously published data. Determination of fluid saturation and reservoir evaluation could be significantly improved by using the new equation.
基金supported by the National Natural Science Foundation of China(projects No.41074103 and 50404001)the National Key Fundamental R & D Project(Grant No.2007CB209601)
文摘The Lattice Gas Automation （LGA） method, which is improved by introducing a reflection coefficient for the border between phases to show its effect on current path, is used in this paper to simulate the current flow in digital rock for investigating the effects of clay content and clay distribution types on the relationship between formation factor（F） and rock porosity（φ）. The digital rock model is constructed by simulating a natural deposit of matrix particles with different shapes and radius. Based on the simulation results, it was found that both dispersed clay and laminated clay can lead to a non-Archie relationship of F-φ. The non-Archie effect of laminated clay on the F-φ relationship was more significant than that of dispersed clay. Moreover, a realistic model is developed in this work for quantitatively describing the effect of clay content （Denoted as Vsh） on parameters a and m. These study results have further demonstrated the validity of LGA in study of electrical transport properties at a pore scale.
