The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
André Revil - One of the best experts on this subject based on the ideXlab platform.
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Streaming Potential Coupling Coefficient and Transport Properties of Unsaturated Carbonate Rocks
Vadose Zone Journal, 2018Co-Authors: Aurélien Cherubini, Adrian Cerepi, Bruno Garcia, André RevilAbstract:We measured the streaming potential Coupling Coefficient of natural saturated and unsaturated carbonate rocks. Saturation was achieved with NaCl brines with salinities ranging from 2 ´ 10−3 to 2.0 mol L−1. The magnitude of the Coupling Coefficient increased with decreasing salinity, similarly to the trend observed for sandstones. The permeability had a low impact on the values of the streaming potential Coupling Coefficient at high and low salinity. The zeta potential was calculated at full saturation using a modified version of the Helmholtz–Smoluchowski equation that accounts for surface electrical conductivity. Under atmospheric conditions, the magnitude of the zeta potential decreased with the increase in salinity. We also explored the relationships between the streaming potential Coupling Coefficient and water saturation in three partially saturated limestones using a steady-state flow experiment. We found good agreement between the van Genuchten approach and experimental data, and fitted both the relative permeability and capillary pressure curves with the same value of the van Genuchten exponent mv. We validated the predictive water relative permeability model described by Revil in water-wet rocks when the second fluid phase is non-polar.
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Streaming potential Coupling Coefficient in unsaturated carbonate rocks
Geophysical Journal International, 2017Co-Authors: Adrian Cerepi, Aurélien Cherubini, Bruno Garcia, Hervé Deschamps, André RevilAbstract:The seismoelectric and self-potential methods are showing promises to characterize both the vadose zone of the Earth, hydrocarbon reservoirs and CO2 sequestration. That said, the dependence of a key parameter, the streaming Coupling Coefficient, with the saturation remains highly debated. We explore here the relationship between the streaming potential Coupling Coefficient, the electrical resistivity, the capillary pressure curves and the permeability in two saturated and partially saturated carbonate rocks characterized by distinct textures. We investigate a limestone from the Paris basin (the Brauvilliers limestone) and a dolostone from the Aquitain basin (sample labeled LS2), both in France. The two core samples are characterized in terms of their porosity and intrinsic formation factor. A new core flooding system is used to measure simultaneously and, for the first time, both the relative permeability, the resistivity index and the streaming potential Coupling Coefficient in steady-state two-phase flow conditions as a function of the saturation with CO2 or N2. The results are compared with a recently developed theoretical model, which can accommodate either the Brooks and Corey model or the van Genuchten model for the capillary pressure curves. This model is predicting a set of relationships between the streaming potential Coupling Coefficient, the relative permeability and the second Archie's exponent. We found a good agreement between the model based on the van Genuchten approach and experimental data, but still we could not fit all the curves with the same value of the pore size index λ or van Genuchten exponent mv especially for the relative permeability.
Nimal Perera - One of the best experts on this subject based on the ideXlab platform.
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Coupling Coefficient and lateral vibration of slender suspension footbridges
2008Co-Authors: Ming-hui Huang, David Thambiratnam, Nimal PereraAbstract:Slender footbridges are known to suffer excessive lateral vibration which is not well understood at present. A suspension footbridge model with reverse profiled cables is proposed to investigate the vibration characteristics of slender shallow suspension footbridges and two types of cable configurations are considered in this paper. It is found that suspension footbridges with shallow cable profiles often have coupled vibration modes which can be described by a "Coupling Coefficient" defined as the ratio of vertical component to the lateral one. Numerical results show that the Coupling Coefficient has a significant effect on the lateral dynamic amplification factor (DAF), and larger DAF of lateral vibration is expected for the vibration mode with smaller Coupling Coefficient.
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Coupling Coefficient and lateral vibration of slender suspension footbridges
Computers & Structures, 2008Co-Authors: Ming-hui Huang, David Thambiratnam, Nimal PereraAbstract:Slender footbridges are known to suffer excessive lateral vibration which is not well understood at present. A suspension footbridge model with reverse profiled cables is proposed to investigate the vibration characteristics of slender shallow suspension footbridges and two types of cable configurations are considered in this paper. It is found that suspension footbridges with shallow cable profiles often have coupled vibration modes which can be described by a ''Coupling Coefficient'' defined as the ratio of vertical component to the lateral one. Numerical results show that the Coupling Coefficient has a significant effect on the lateral dynamic amplification factor (DAF). Small Coupling Coefficients can induce large DAF in lateral modes.
Ming-hui Huang - One of the best experts on this subject based on the ideXlab platform.
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Coupling Coefficient and lateral vibration of slender suspension footbridges
2008Co-Authors: Ming-hui Huang, David Thambiratnam, Nimal PereraAbstract:Slender footbridges are known to suffer excessive lateral vibration which is not well understood at present. A suspension footbridge model with reverse profiled cables is proposed to investigate the vibration characteristics of slender shallow suspension footbridges and two types of cable configurations are considered in this paper. It is found that suspension footbridges with shallow cable profiles often have coupled vibration modes which can be described by a "Coupling Coefficient" defined as the ratio of vertical component to the lateral one. Numerical results show that the Coupling Coefficient has a significant effect on the lateral dynamic amplification factor (DAF), and larger DAF of lateral vibration is expected for the vibration mode with smaller Coupling Coefficient.
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Coupling Coefficient and lateral vibration of slender suspension footbridges
Computers & Structures, 2008Co-Authors: Ming-hui Huang, David Thambiratnam, Nimal PereraAbstract:Slender footbridges are known to suffer excessive lateral vibration which is not well understood at present. A suspension footbridge model with reverse profiled cables is proposed to investigate the vibration characteristics of slender shallow suspension footbridges and two types of cable configurations are considered in this paper. It is found that suspension footbridges with shallow cable profiles often have coupled vibration modes which can be described by a ''Coupling Coefficient'' defined as the ratio of vertical component to the lateral one. Numerical results show that the Coupling Coefficient has a significant effect on the lateral dynamic amplification factor (DAF). Small Coupling Coefficients can induce large DAF in lateral modes.
Adrian Cerepi - One of the best experts on this subject based on the ideXlab platform.
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Streaming Potential Coupling Coefficient and Transport Properties of Unsaturated Carbonate Rocks
Vadose Zone Journal, 2018Co-Authors: Aurélien Cherubini, Adrian Cerepi, Bruno Garcia, André RevilAbstract:We measured the streaming potential Coupling Coefficient of natural saturated and unsaturated carbonate rocks. Saturation was achieved with NaCl brines with salinities ranging from 2 ´ 10−3 to 2.0 mol L−1. The magnitude of the Coupling Coefficient increased with decreasing salinity, similarly to the trend observed for sandstones. The permeability had a low impact on the values of the streaming potential Coupling Coefficient at high and low salinity. The zeta potential was calculated at full saturation using a modified version of the Helmholtz–Smoluchowski equation that accounts for surface electrical conductivity. Under atmospheric conditions, the magnitude of the zeta potential decreased with the increase in salinity. We also explored the relationships between the streaming potential Coupling Coefficient and water saturation in three partially saturated limestones using a steady-state flow experiment. We found good agreement between the van Genuchten approach and experimental data, and fitted both the relative permeability and capillary pressure curves with the same value of the van Genuchten exponent mv. We validated the predictive water relative permeability model described by Revil in water-wet rocks when the second fluid phase is non-polar.
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Streaming potential Coupling Coefficient in unsaturated carbonate rocks
Geophysical Journal International, 2017Co-Authors: Adrian Cerepi, Aurélien Cherubini, Bruno Garcia, Hervé Deschamps, André RevilAbstract:The seismoelectric and self-potential methods are showing promises to characterize both the vadose zone of the Earth, hydrocarbon reservoirs and CO2 sequestration. That said, the dependence of a key parameter, the streaming Coupling Coefficient, with the saturation remains highly debated. We explore here the relationship between the streaming potential Coupling Coefficient, the electrical resistivity, the capillary pressure curves and the permeability in two saturated and partially saturated carbonate rocks characterized by distinct textures. We investigate a limestone from the Paris basin (the Brauvilliers limestone) and a dolostone from the Aquitain basin (sample labeled LS2), both in France. The two core samples are characterized in terms of their porosity and intrinsic formation factor. A new core flooding system is used to measure simultaneously and, for the first time, both the relative permeability, the resistivity index and the streaming potential Coupling Coefficient in steady-state two-phase flow conditions as a function of the saturation with CO2 or N2. The results are compared with a recently developed theoretical model, which can accommodate either the Brooks and Corey model or the van Genuchten model for the capillary pressure curves. This model is predicting a set of relationships between the streaming potential Coupling Coefficient, the relative permeability and the second Archie's exponent. We found a good agreement between the model based on the van Genuchten approach and experimental data, but still we could not fit all the curves with the same value of the pore size index λ or van Genuchten exponent mv especially for the relative permeability.
Matthew D. Jackson - One of the best experts on this subject based on the ideXlab platform.
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Salinity dependence of the thermoelectric Coupling Coefficient in brine‐saturated sandstones
Geophysical Research Letters, 2010Co-Authors: Eli Leinov, J. Vinogradov, Matthew D. JacksonAbstract:[1] We report measurements of the thermoelectric Coupling Coefficient in intact sandstone samples saturated with NaCl brine at concentrations ranging from 1 × 10−4 to 1 M. Our measurements account for temperature-dependent electrode effects. We also present a model for the salinity dependence of the thermoelectric Coupling Coefficient which yields a close match to the experimental data. At low salinity, the measured Coupling Coefficient exhibits the salinity dependence predicted for a perfect membrane, while at high salinity, the Coupling Coefficient follows that predicted for an uncharged porous medium. Measured values of the Coupling Coefficient range from 0.370 mVK−1 at low salinity (1 × 10−4 M), to 0.055 mVK−1 at high salinity (1 M).
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Salinity dependence of the thermoelectric Coupling Coefficient in brine-saturated sandstones
Geophysical Research Letters, 2010Co-Authors: Eli Leinov, J. Vinogradov, Matthew D. JacksonAbstract:[1] We report measurements of the thermoelectric Coupling Coefficient in intact sandstone samples saturated with NaCl brine at concentrations ranging from 1 × 10−4 to 1 M. Our measurements account for temperature-dependent electrode effects. We also present a model for the salinity dependence of the thermoelectric Coupling Coefficient which yields a close match to the experimental data. At low salinity, the measured Coupling Coefficient exhibits the salinity dependence predicted for a perfect membrane, while at high salinity, the Coupling Coefficient follows that predicted for an uncharged porous medium. Measured values of the Coupling Coefficient range from 0.370 mVK−1 at low salinity (1 × 10−4 M), to 0.055 mVK−1 at high salinity (1 M).
