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An Zhao - One of the best experts on this subject based on the ideXlab platform.
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void fraction measurement of oil gas water Three Phase Flow using mutually perpendicular ultrasonic sensor
Sensors, 2020Co-Authors: An ZhaoAbstract:The complex Flow structure and interfacial effect in oil–gas–water Three-Phase Flow have made the void fraction measurement a challenging problem. This paper reports on the void fraction measurement of oil–gas–water Three-Phase Flow using a mutually perpendicular ultrasonic sensor (MPUS). Two pairs of ultrasonic probes are installed on the same pipe section to measure the void fraction. With the aid of the finite element method, we first optimize the emission frequency and geometry parameters of MPUS through examining its sensitivity field distribution. Afterward, the oil–gas–water Three-Phase Flow experiment was carried out in a vertical upward pipe with a diameter of 20 mm to investigate the responses of MPUS. Then, the void fraction prediction models associated with Flow patterns (bubble Flow, slug Flow, and churn Flow) were established. Compared to the quick closing valves, MPUS obtained a favorable accuracy for void fraction measurement with absolute average percentage error equaling 8.983%, which indicates that MPUS can satisfactorily measure the void fraction of oil–gas–water Three-Phase Flow.
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Void Fraction Measurement of Oil–Gas–Water Three-Phase Flow Using Mutually Perpendicular Ultrasonic Sensor
Sensors, 2020Co-Authors: An ZhaoAbstract:The complex Flow structure and interfacial effect in oil–gas–water Three-Phase Flow have made the void fraction measurement a challenging problem. This paper reports on the void fraction measurement of oil–gas–water Three-Phase Flow using a mutually perpendicular ultrasonic sensor (MPUS). Two pairs of ultrasonic probes are installed on the same pipe section to measure the void fraction. With the aid of the finite element method, we first optimize the emission frequency and geometry parameters of MPUS through examining its sensitivity field distribution. Afterward, the oil–gas–water Three-Phase Flow experiment was carried out in a vertical upward pipe with a diameter of 20 mm to investigate the responses of MPUS. Then, the void fraction prediction models associated with Flow patterns (bubble Flow, slug Flow, and churn Flow) were established. Compared to the quick closing valves, MPUS obtained a favorable accuracy for void fraction measurement with absolute average percentage error equaling 8.983%, which indicates that MPUS can satisfactorily measure the void fraction of oil–gas–water Three-Phase Flow.
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Nonlinear multi-scale dynamic stability of oil–gas–water Three-Phase Flow in vertical upward pipe
Chemical Engineering Journal, 2016Co-Authors: Lian-xin Zhuang, An Zhao, Lu-sheng Zhai, Yi TangAbstract:Abstract Characterizing stability and nonlinearity underlying oil–water–gas Three-Phase Flow is a challenging problem of significant importance. We carry out experiments and measure the fluctuation signals from a rotating electric field conductance sensor with eight electrodes. We use recurrence plot and adaptive optimal kernel time–frequency representation to recognize different oil–water–gas Three-Phase Flow patterns from experimental measurements. Then we employ multi-scale weighted complexity entropy causality plane (MS-WCECP) to explore the nonlinear characteristics for five typical oil–water–gas Three-Phase Flow structures. The results suggest that our method enables to indicate Flow pattern transitions. In particular, with the increase of scales, more information will be lost. Slug Flow ends up in chaotic region, representing high complexity; Churn Flow falls down from the chaotic to the random noise area, indicating the decreasing stability; while the drop degree of bubble Flow is the biggest, suggesting that bubble Flow has the most randomness. These findings demonstrate that multi-scale weighted complexity entropy causality plane can effectively depict the transitions of Three-Phase Flow structures and serve as a useful tool for probing the nonlinear dynamics of the Three-Phase Flows.
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Multi-Scale Long-Range Magnitude and Sign Correlations in Vertical Upward Oil–Gas–Water Three-Phase Flow
Zeitschrift für Naturforschung A, 2016Co-Authors: An Zhao, Xia YangAbstract:Abstract In this article we apply an approach to identify the oil–gas–water Three-Phase Flow patterns in vertical upwards 20 mm inner-diameter pipe based on the conductance fluctuating signals. We use the approach to analyse the signals with long-range correlations by decomposing the signal increment series into magnitude and sign series and extracting their scaling properties. We find that the magnitude series relates to nonlinear properties of the original time series, whereas the sign series relates to the linear properties. The research shows that the oil–gas–water Three-Phase Flows (slug Flow, churn Flow, bubble Flow) can be classified by a combination of scaling exponents of magnitude and sign series. This study provides a new way of characterising linear and nonlinear properties embedded in oil–gas–water Three-Phase Flows.
Martin J. Blunt - One of the best experts on this subject based on the ideXlab platform.
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Three dimensional mixed wet random pore scale network modeling of two and Three Phase Flow in porous media i model description
Physical Review E, 2005Co-Authors: Mohammad Piri, Martin J. BluntAbstract:We present a Three-dimensional network model to simulate two- and Three-Phase capillary dominated processes at the pore level. The displacement mechanisms incorporated in the model are based on the physics of multiPhase Flow observed in micromodel experiments. All the important features of immiscible fluid Flow at the pore scale, such as wetting layers, spreading layers of the intermediate-wet Phase, hysteresis, and wettability alteration are implemented in the model. Wettability alteration allows any values for the advancing and receding oil-water, gas-water, and gas-oil contact angles to be assigned. Multiple Phases can be present in each pore or throat (element), in wetting and spreading layers, as well as occupying the center of the pore space. In all, some 30 different generic fluid configurations for two- and Three-Phase Flow are analyzed. Double displacement and layer formation are implemented as well as direct two-Phase displacement and layer collapse events. Every element has a circular, square, or triangular cross section. A random network that represents the pore space in Berea sandstone is used in this study. The model computes relative permeabilities, saturation paths, and capillary pressures for any displacement sequence. A methodology to track a given Three-Phase saturation path is presented that enables us to compare predicted and measured relative permeabilities on a point-by-point basis. A robust displacement-based clustering algorithm is also presented.
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Elliptic Regions and Stable Solutions for Three-Phase Flow in Porous Media
Transport in Porous Media, 2002Co-Authors: Matthew D. Jackson, Martin J. BluntAbstract:In the limit of zero capillary pressure, solutions to the equations governing Three-Phase Flow, obtained using common empirical relative permeability models, exhibit complex wavespeeds for certain saturation values (elliptic regions) that result in unstable and non-unique solutions. We analyze a simple but physically realizable pore-scale model: a bundle of cylindrical capillary tubes, to investigate whether the presence of these elliptic regions is an artifact of using unphysical relative permeabilities. Without gravity, the model does not yield elliptic regions unless the most non-wetting Phase is the most viscous and the most wetting Phase is the least viscous. With gravity, the model yields elliptic regions for any combination of viscosities, and these regions occupy a significant fraction of the saturation space. We then present converged, stable numerical solutions for one-dimensional Flow, which include capillary pressure. These demonstrate that, even when capillary forces are small relative to viscous forces, they have a significant effect on solutions which cross or enter the elliptic region. We conclude that elliptic regions can occur for a physically realizable model of a porous medium, and that capillary pressure should be included explicitly in Three-Phase numerical simulators to obtain stable, physically meaningful solutions which reproduce the correct sequence of saturation changes.
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effects of wettability on Three Phase Flow in porous media
Journal of Physical Chemistry B, 2000Co-Authors: Martin J. BluntAbstract:We study the effects of rock wettability on the Flow of oil, water, and gas in hydrocarbon reservoirs. We describe the Three-Phase fluid configurations and displacement processes in a pore of polygonal cross section. Initially water-filled, water-wet pores are invaded by oil, representing primary oil migration. Where oil directly contacts the solid surface, the surface will change its wettability. We then consider water injection followed by gas injection for any possible combination of oil/water, gas/water, and gas/oil contact angles. We find the capillary pressures for the different displacement processes and determine the circumstances under which the various fluid configurations are stable. Using empirical expressions for the Phase conductances, we find Three-Phase relative permeabilites for a bundle of pores of different sizes with constant triangular cross sections. For gas injection, we show that the oil remains connected in wetting layers down to low oil saturation with a characteristic layer drai...
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Theoretical Analysis of Three Phase Flow Experiments in Porous Media
Software - Practice and Experience, 1996Co-Authors: Akshay Sahni, Rafael Guzman, Martin J. BluntAbstract:This paper presents a framework for analyzing Three Phase Flow experiments in porous media. We analyze previously published data from a dynamic displacement experiment, where Three Phase relative permeabilities have been measured. The relative permeability of each Phase is, to a good approximation, a polynomial function of the saturation of that Phase. Then analytically, we calculate the saturation paths and recovery for the experiments using the method of characteristics. The predicted paths agree well with the experimental measurements, and with one-dimensional numerical solutions.
Mohammad Piri - One of the best experts on this subject based on the ideXlab platform.
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Pore-Scale Network Modeling of Three-Phase Flow Based on Thermodynamically Consistent Threshold Capillary Pressures. I. Cusp Formation and Collapse
Transport in Porous Media, 2017Co-Authors: Arsalan Zolfaghari, Mohammad PiriAbstract:We present a pore-scale network model of two- and Three-Phase Flow in disordered porous media. The model reads Three-dimensional pore networks representing the pore space in different porous materials. It simulates wide range of two- and Three-Phase pore-scale displacements in porous media with mixed-wet wettability. The networks are composed of pores and throats with circular and angular cross sections. The model allows the presence of multiple Phases in each angular pore. It uses Helmholtz free energy balance and Mayer–Stowe–Princen (MSP) method to compute threshold capillary pressures for two- and Three-Phase displacements (fluid configuration changes) based on pore wettability, pore geometry, interfacial tension, and initial pore fluid occupancy. In particular, it generates thermodynamically consistent threshold capillary pressures for wetting and spreading fluid layers resulting from different displacement events. Threshold capillary pressure equations are presented for various possible fluid configuration changes. By solving the equations for the most favorable displacements, we show how threshold capillary pressures and final fluid configurations may vary with wettability, shape factor, and the maximum capillary pressure reached during preceding displacement processes. A new cusp pore fluid configuration is introduced to handle the connectivity of the intermediate wetting Phase at low saturations and to improve model’s predictive capabilities. Based on energy balance and geometric equations, we show that, for instance, a gas-to-oil piston-like displacement in an angular pore can result in a pore fluid configuration with no oil, with oil layers, or with oil cusps. Oil layers can then collapse to form cusps. Cusps can shrink and disappear leaving no oil behind. Different displacement mechanisms for layer and cusp formation and collapse based on the MSP analysis are implemented in the model. We introduce four different layer collapse rules. A selected collapse rule may generate different corner configuration depending on fluid occupancies of the neighboring elements and capillary pressures. A new methodology based on the MSP method is introduced to handle newly created gas/water interfaces that eliminates inconsistencies in relation between capillary pressures and pore fluid occupancies. Minimization of Helmholtz free energy for each relevant displacement enables the model to accurately determine the most favorable displacement, and hence, improve its predictive capabilities for relative permeabilities, capillary pressures, and residual saturations. The results indicate that absence of oil cusps and the previously used geometric criterion for the collapse of oil layers could yield lower residual oil saturations than the experimentally measured values in two- and Three-Phase systems.
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in situ characterization of wettability and pore scale displacements during two and Three Phase Flow in natural porous media
Advances in Water Resources, 2016Co-Authors: Mahdi Khishvand, A H Alizadeh, Mohammad PiriAbstract:Abstract We establish a unique approach to measure in-situ contact angle from micro-CT images acquired during two- and Three-Phase miniature core-flooding experiments in order to overcome the uncertainties associated with conventional contact angle measurement techniques. The measurements are used to quantify the wettability behavior of the rock and explain pore-level displacement events occurring in Three-Phase Flow. Six two-Phase experiments are performed on individual core samples with Three pairs of fluids, i.e., oil-brine, gas-oil, and gas-brine, and under two thermodynamic conditions: (a) binary-equilibrated, when only the two respective Phases are at equilibrium and (b) ternary-equilibrated, when all Three Phases are equilibrated and only the two desired fluids are injected into the core. A Three-Phase experiment set is also performed under ternary-equilibrated conditions, which includes gas injection, a waterflood, and an oilflood process. All experiments are performed on Berea miniature core samples using a nonspreading brine-oil-gas fluid system. We measure receding and advancing contact angles at arc menisci and main terminal menisci for the two-Phase binary-equilibrated experiments and characterize contact angle hysteresis for each fluid pair. Contact angle hysteresis values are almost identical for all fluid pairs. The results of the two-Phase binary- and ternary-equilibrated experiments show similar contact angle distributions for each fluid pair. Contact angle distributions during the Three-Phase Flow experiment are analyzed to develop new insights into relevant complex displacement mechanisms. The results indicate that, during gas injection, the majority of displacements involving oil and water are oil-to-water events. It is observed that, during the waterflood, both oil-to-gas and gas-to-oil displacement events take place. However, the relative frequency of the former is greater. For the oilflood, gas-water interfaces only slightly hinge in pore elements. Pore-scale fluid occupancy maps and the Bartell–Osterhoff constraint verify the above-mentioned findings.
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Three dimensional mixed wet random pore scale network modeling of two and Three Phase Flow in porous media i model description
Physical Review E, 2005Co-Authors: Mohammad Piri, Martin J. BluntAbstract:We present a Three-dimensional network model to simulate two- and Three-Phase capillary dominated processes at the pore level. The displacement mechanisms incorporated in the model are based on the physics of multiPhase Flow observed in micromodel experiments. All the important features of immiscible fluid Flow at the pore scale, such as wetting layers, spreading layers of the intermediate-wet Phase, hysteresis, and wettability alteration are implemented in the model. Wettability alteration allows any values for the advancing and receding oil-water, gas-water, and gas-oil contact angles to be assigned. Multiple Phases can be present in each pore or throat (element), in wetting and spreading layers, as well as occupying the center of the pore space. In all, some 30 different generic fluid configurations for two- and Three-Phase Flow are analyzed. Double displacement and layer formation are implemented as well as direct two-Phase displacement and layer collapse events. Every element has a circular, square, or triangular cross section. A random network that represents the pore space in Berea sandstone is used in this study. The model computes relative permeabilities, saturation paths, and capillary pressures for any displacement sequence. A methodology to track a given Three-Phase saturation path is presented that enables us to compare predicted and measured relative permeabilities on a point-by-point basis. A robust displacement-based clustering algorithm is also presented.
Zhen-ya Wang - One of the best experts on this subject based on the ideXlab platform.
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Attractor comparison analysis for characterizing vertical upward oil—gas—water Three-Phase Flow
Chinese Physics B, 2014Co-Authors: Jun-ying Zhao, Meng Du, Zhen-ya WangAbstract:We investigate the dynamic characteristics of oil—gas—water Three-Phase Flow in terms of chaotic attractor comparison. In particular, we extract a statistic to characterize the dynamical difference in attractor probability distribution. We first take time series from Logistic chaotic system with different parameters as examples to demonstrate the effectiveness of the method. Then we use this method to investigate the experimental signals from oil—gas—water Three-Phase Flow. The results indicate that the extracted statistic is very sensitive to the change of Flow parameters and can gain a quantitatively insight into the dynamic characteristics of different Flow patterns.
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nonlinear dynamical analysis of large diameter vertical upward oil gas water Three Phase Flow pattern characteristics
Chemical Engineering Science, 2010Co-Authors: Zhen-ya Wang, Yanbo Zong, Tengda WangAbstract:Abstract Based on two kinds of signals measured from mini-conductance probe array and vertical multi-electrode array (VMEA) conductance sensor, we study oil–gas–water Three-Phase Flow in a vertical upward 125 mm ID pipe. Using the ratio of oil Flowrate to total liquid Flowrate (fo) and the superficial gas velocity (Usg), we draw the six different Flow pattern maps under four total mixture liquid Flowrates. In addition, we indicate that: (a) the increase of fo makes oil in water type slug Flow occur at lower Usg; (b) for large diameter pipe and low Flow velocity, the Phase inversion of liquids occurs at about fo=0.9 and the increase of Usg makes the Phase inversion of liquids move to low fo. Furthermore, we investigate the nonlinear dynamical characteristics of five water continuous Phase Flow patterns in terms of chaotic attractor morphological description and complexity measures (Lempel–Ziv complexity and approximate entropy), and find that: (a) the chaotic attractor morphological characteristics can identify Three-Phase Flow patterns; (b) the combination of Lempel–Ziv complexity and approximate entropy can serve as a unique classification criterion of Three-Phase Flow patterns. In this regard, the nonlinear analysis of conductance fluctuating signals can give an effective indicator to understand and identify the oil–gas–water Three-Phase Flow pattern characteristics.
Tengda Wang - One of the best experts on this subject based on the ideXlab platform.
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nonlinear dynamical analysis of large diameter vertical upward oil gas water Three Phase Flow pattern characteristics
Chemical Engineering Science, 2010Co-Authors: Zhen-ya Wang, Yanbo Zong, Tengda WangAbstract:Abstract Based on two kinds of signals measured from mini-conductance probe array and vertical multi-electrode array (VMEA) conductance sensor, we study oil–gas–water Three-Phase Flow in a vertical upward 125 mm ID pipe. Using the ratio of oil Flowrate to total liquid Flowrate (fo) and the superficial gas velocity (Usg), we draw the six different Flow pattern maps under four total mixture liquid Flowrates. In addition, we indicate that: (a) the increase of fo makes oil in water type slug Flow occur at lower Usg; (b) for large diameter pipe and low Flow velocity, the Phase inversion of liquids occurs at about fo=0.9 and the increase of Usg makes the Phase inversion of liquids move to low fo. Furthermore, we investigate the nonlinear dynamical characteristics of five water continuous Phase Flow patterns in terms of chaotic attractor morphological description and complexity measures (Lempel–Ziv complexity and approximate entropy), and find that: (a) the chaotic attractor morphological characteristics can identify Three-Phase Flow patterns; (b) the combination of Lempel–Ziv complexity and approximate entropy can serve as a unique classification criterion of Three-Phase Flow patterns. In this regard, the nonlinear analysis of conductance fluctuating signals can give an effective indicator to understand and identify the oil–gas–water Three-Phase Flow pattern characteristics.