The Experts below are selected from a list of 2175 Experts worldwide ranked by ideXlab platform
Hongquan Zhang - One of the best experts on this subject based on the ideXlab platform.
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modeling flow pattern transitions in electrical Submersible Pump under gassy flow conditions
2019Co-Authors: Jiecheng Zhang, Qingqi Zhao, Jianlin Peng, Hongquan ZhangAbstract:Abstract Gas entrainment is frequently encountered in electrical Submersible Pumps (ESP). When occurring, ESP suffers from moderate to severe performance degradation accompanied by unstable operations, depending on the inlet gas volumetric fraction (GVF) and Pump rotational speed. The resulted pressure surging and instabilities may cause Pump vibrations and short run-life. For a better design of ESP-based production system, the mechanistic model is needed to predict its performance under gas-liquid flow conditions. Similar to multiphase pipe flow, the flow pattern identification and classification inside a rotating ESP is important. In this paper, a new mechanistic model is proposed, which can map different flow patterns inside ESP with gas presence. Experimental results reveal that the boosting pressure of ESP degrades as GVF increases. With ESP's H-Q performance curves obtained, the flow patterns including dispersed bubble flow, bubbly flow, intermittent flow and segregated flow can be identified by deflection points on H-Q curves (Gamboa and Prado, 2008). The transition boundaries between different flow patterns are mapped. Starting from the free body diagram on a stable bubble in the rotating flow field, the transition boundaries of dispersed bubble flow to bubbly flow and bubbly flow to intermittent flow are formulated. Based on the combined momentum equation, the transition criterion of intermittent flow to segregated flow is derived. The flow pattern map predicted by mechanistic model agrees well with that detected from the experimental H-Q curves of ESP under gassy flow conditions.
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a numerical study on flow patterns inside an electrical Submersible Pump esp and comparison with visualization experiments
2019Co-Authors: Jianjun Zhu, Jiecheng Zhang, Haiwen Zhu, Hongquan ZhangAbstract:Abstract This paper presents a numerical study of flow pattern recognition inside the rotating impeller of an electrical Submersible Pump (ESP) using the transient multiphase Computational Fluid Dynamics (CFD) simulations. The calculation domain is constructed based on the previous experimental facility for visualizing flow patterns in an ESP (Barrios (2007)). The high-quality structured mesh comprising hexahedral grids is generated using multi-block technique in ANSYS ICEM. For CFD simulations, the realizable k-e turbulence model with volume of fluid (VOF) and Eulerian-Eulerian multiphase models is successfully implemented in ANSYS Fluent solver. The sliding mesh technique is applied to interfaces where rotating and stationary parts interact. By incorporating the same boundary conditions as Barrios experimental study, three flow cases with constant gas flow rates and varying liquid flow rates are selected to conduct numerical simulations. The comparison of simulation results with Barrios’ observations shows that the Eulerian-Eulerian multiphase model is superior to VOF model for simulating gas-liquid two-phase flow in a rotating ESP. The single-phase simulation results match catalog curves, which validates the numerical methodology. For two-phase simulations, the simulated flow patterns using Eulerian-Eulerian model agree well with visualization experiments. Different flow patterns prevailing inside the rotating ESP impeller are captured. At low gas flow rate, bubbles are dispersed in liquid phase, and the flow pattern is categorized as dispersed bubble flow. As gas flow rate increases, bubbles can accumulate and coalesce, causing large gas-pocket formation leading to intermittent/slug flow. Transient multiphase CFD simulation is an efficient and reliable tool to predict flow patterns inside ESPs.
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surfactant effect on air water flow in a multistage electrical Submersible Pump esp
2018Co-Authors: Jianjun Zhu, Jiecheng Zhang, Haiwen Zhu, Zhihua Wang, Ruben Cuamatzimelendez, Jose Alberto Martinez Farfan, Hongquan ZhangAbstract:Abstract The surfactant effect on ESP boosting pressure under air–water flow is studied in this paper. A two-phase flow loop comprising a 7.62 cm diameter stainless steel liquid loop and 1.25 cm diameter gas loop is built up to conduct experimental measurements. A radial-type ESP with 14 stages assembled in series is installed on the testing bench. Pressure ports are drilled at inter-stage to measure the stage-by-stage pressure increment. The surfactant, isopropanol (IPA) is injected to change the interfacial properties of working fluids. Experiments are carried out with mapping and surging test schemes to evaluate Pump behaviors at different operational conditions. ESP pressure increment under single-phase water flow agrees well with the catalog curves. For mapping tests without surfactant injection, ESP performance suffers from a severe degradation as gas flow rate increases. High gas entrainment rate causes oscillations of liquid flow rate and Pump boosting pressure, featured by the instabilities of ESP operations. A sudden drop of ESP pressure increment, termed as pressure surging, occurs at the critical inlet gas volumetric fraction (GVF). For a larger rotational speed, the critical GVF is higher. With surfactant injection, ESP boosting pressure improves significantly. At different GVFs, only mild degradation is observed. Pressure surging phenomenon disappears. Further, liquid flow rate and Pump boosting pressure are more stable at high GVFs compared to experimental data without surfactant injection.
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experimental study and mechanistic modeling of pressure surging in electrical Submersible Pump
2017Co-Authors: Jianjun Zhu, Xiaozhe Guo, Fachun Liang, Hongquan ZhangAbstract:Abstract Gas entrainment is frequently encountered in crude oil production with electrical Submersible Pumps (ESP). Previous studies revealed that the increase of gas entrainment rate in ESPs results in mild degradation of boosting pressure followed by a drastic drop. This critical condition, termed as pressure surging, significantly affects ESP's operational stability and run-life. In this paper, the pressure surging phenomenon in ESPs is studied through experimental measurements and mechanistic modeling. A 7.62-cm two-phase flow loop with a 14-stage radial-type ESP is used for testing Pump performance under single- and two-phase flow conditions. The stage-by-stage boosting pressure with different gas entrainment rates is measured. Effects of intake pressure, gas volumetric fraction (GVF) and rotational speeds on the ESP two-phase pressure increment are investigated. Experimental results show that the boosting pressure of ESP under gassy flow conditions varies significantly with inlet GVFs and fluid properties. For low GVFs ( 7%), which triggers ESP's unstable operations. A mechanistic model based on the critical bubble diameter in rotating multiphase flow field is developed to predict the surging initiation in ESPs. Compared with experimental results, the model predictions demonstrate good agreement.
Mauricio Prado - One of the best experts on this subject based on the ideXlab platform.
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modeling two phase flow inside an electrical Submersible Pump stage
2011Co-Authors: Lissett Barrios, Mauricio PradoAbstract:Dynamic multiphase flow behavior inside a mixed flow Electrical Submersible Pump (ESP) has been studied experimentally and theoretically for the first time. The overall objectives of this study are to determine the flow patterns and bubble behavior inside the ESP and to predict the operational conditions that cause surging. The theoretical study includes a mechanistic model for the prediction of the flow behavior inside the Pump. The model comprises a one-dimensional force balance to predict occurrence of the stagnant bubbles at the channel intake. This model depends on two important variables, namely the stagnant bubble size and the bubble drag coefficient. The bubble size has been measured and a physically based correlation is presented. A new correlation for the drag coefficient is proposed as a function of rotational speed and Reynolds number. The model enables the prediction of the operational envelope of the ESP, namely the transition to surging.Copyright © 2009 by ASME
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experimental visualization of two phase flow inside an electrical Submersible Pump stage
2009Co-Authors: Lissett Barrios, Mauricio PradoAbstract:Dynamic multiphase flow behavior inside a mixed flow Electrical Submersible Pump (ESP) has been studied experimentally and theoretically for the first time. The overall objectives of this study are to determine the flow patterns and bubble behavior inside the ESP and to predict the operational conditions that cause surging. An experimental facility has been designed and constructed to enable flow pattern visualization inside the second stage of a real ESP. Special high speed instrumentation was selected to acquire visual flow dynamics and bubble size measurements inside the impeller channel. Experimental data was acquired utilizing two types of tests (surging test and bubble diameter measurement test) to completely evaluate the Pump behavior at different operational conditions. A similarity analysis performed for single-phase flow inside the Pump concluded that viscosity effects are negligible compared to the centrifugal field effects for rotational speeds higher than 600 rpm. Therefore, the two-phase flow tests were performed for rotational speeds of 600, 900, 1200, and 1500 rpm. Results showed formation of a large gas pocket at the Pump intake during surging conditions.© 2009 ASME
Jianjun Zhu - One of the best experts on this subject based on the ideXlab platform.
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a numerical study on flow patterns inside an electrical Submersible Pump esp and comparison with visualization experiments
2019Co-Authors: Jianjun Zhu, Jiecheng Zhang, Haiwen Zhu, Hongquan ZhangAbstract:Abstract This paper presents a numerical study of flow pattern recognition inside the rotating impeller of an electrical Submersible Pump (ESP) using the transient multiphase Computational Fluid Dynamics (CFD) simulations. The calculation domain is constructed based on the previous experimental facility for visualizing flow patterns in an ESP (Barrios (2007)). The high-quality structured mesh comprising hexahedral grids is generated using multi-block technique in ANSYS ICEM. For CFD simulations, the realizable k-e turbulence model with volume of fluid (VOF) and Eulerian-Eulerian multiphase models is successfully implemented in ANSYS Fluent solver. The sliding mesh technique is applied to interfaces where rotating and stationary parts interact. By incorporating the same boundary conditions as Barrios experimental study, three flow cases with constant gas flow rates and varying liquid flow rates are selected to conduct numerical simulations. The comparison of simulation results with Barrios’ observations shows that the Eulerian-Eulerian multiphase model is superior to VOF model for simulating gas-liquid two-phase flow in a rotating ESP. The single-phase simulation results match catalog curves, which validates the numerical methodology. For two-phase simulations, the simulated flow patterns using Eulerian-Eulerian model agree well with visualization experiments. Different flow patterns prevailing inside the rotating ESP impeller are captured. At low gas flow rate, bubbles are dispersed in liquid phase, and the flow pattern is categorized as dispersed bubble flow. As gas flow rate increases, bubbles can accumulate and coalesce, causing large gas-pocket formation leading to intermittent/slug flow. Transient multiphase CFD simulation is an efficient and reliable tool to predict flow patterns inside ESPs.
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surfactant effect on air water flow in a multistage electrical Submersible Pump esp
2018Co-Authors: Jianjun Zhu, Jiecheng Zhang, Haiwen Zhu, Zhihua Wang, Ruben Cuamatzimelendez, Jose Alberto Martinez Farfan, Hongquan ZhangAbstract:Abstract The surfactant effect on ESP boosting pressure under air–water flow is studied in this paper. A two-phase flow loop comprising a 7.62 cm diameter stainless steel liquid loop and 1.25 cm diameter gas loop is built up to conduct experimental measurements. A radial-type ESP with 14 stages assembled in series is installed on the testing bench. Pressure ports are drilled at inter-stage to measure the stage-by-stage pressure increment. The surfactant, isopropanol (IPA) is injected to change the interfacial properties of working fluids. Experiments are carried out with mapping and surging test schemes to evaluate Pump behaviors at different operational conditions. ESP pressure increment under single-phase water flow agrees well with the catalog curves. For mapping tests without surfactant injection, ESP performance suffers from a severe degradation as gas flow rate increases. High gas entrainment rate causes oscillations of liquid flow rate and Pump boosting pressure, featured by the instabilities of ESP operations. A sudden drop of ESP pressure increment, termed as pressure surging, occurs at the critical inlet gas volumetric fraction (GVF). For a larger rotational speed, the critical GVF is higher. With surfactant injection, ESP boosting pressure improves significantly. At different GVFs, only mild degradation is observed. Pressure surging phenomenon disappears. Further, liquid flow rate and Pump boosting pressure are more stable at high GVFs compared to experimental data without surfactant injection.
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experimental study and mechanistic modeling of pressure surging in electrical Submersible Pump
2017Co-Authors: Jianjun Zhu, Xiaozhe Guo, Fachun Liang, Hongquan ZhangAbstract:Abstract Gas entrainment is frequently encountered in crude oil production with electrical Submersible Pumps (ESP). Previous studies revealed that the increase of gas entrainment rate in ESPs results in mild degradation of boosting pressure followed by a drastic drop. This critical condition, termed as pressure surging, significantly affects ESP's operational stability and run-life. In this paper, the pressure surging phenomenon in ESPs is studied through experimental measurements and mechanistic modeling. A 7.62-cm two-phase flow loop with a 14-stage radial-type ESP is used for testing Pump performance under single- and two-phase flow conditions. The stage-by-stage boosting pressure with different gas entrainment rates is measured. Effects of intake pressure, gas volumetric fraction (GVF) and rotational speeds on the ESP two-phase pressure increment are investigated. Experimental results show that the boosting pressure of ESP under gassy flow conditions varies significantly with inlet GVFs and fluid properties. For low GVFs ( 7%), which triggers ESP's unstable operations. A mechanistic model based on the critical bubble diameter in rotating multiphase flow field is developed to predict the surging initiation in ESPs. Compared with experimental results, the model predictions demonstrate good agreement.
Lissett Barrios - One of the best experts on this subject based on the ideXlab platform.
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modeling two phase flow inside an electrical Submersible Pump stage
2011Co-Authors: Lissett Barrios, Mauricio PradoAbstract:Dynamic multiphase flow behavior inside a mixed flow Electrical Submersible Pump (ESP) has been studied experimentally and theoretically for the first time. The overall objectives of this study are to determine the flow patterns and bubble behavior inside the ESP and to predict the operational conditions that cause surging. The theoretical study includes a mechanistic model for the prediction of the flow behavior inside the Pump. The model comprises a one-dimensional force balance to predict occurrence of the stagnant bubbles at the channel intake. This model depends on two important variables, namely the stagnant bubble size and the bubble drag coefficient. The bubble size has been measured and a physically based correlation is presented. A new correlation for the drag coefficient is proposed as a function of rotational speed and Reynolds number. The model enables the prediction of the operational envelope of the ESP, namely the transition to surging.Copyright © 2009 by ASME
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experimental visualization of two phase flow inside an electrical Submersible Pump stage
2009Co-Authors: Lissett Barrios, Mauricio PradoAbstract:Dynamic multiphase flow behavior inside a mixed flow Electrical Submersible Pump (ESP) has been studied experimentally and theoretically for the first time. The overall objectives of this study are to determine the flow patterns and bubble behavior inside the ESP and to predict the operational conditions that cause surging. An experimental facility has been designed and constructed to enable flow pattern visualization inside the second stage of a real ESP. Special high speed instrumentation was selected to acquire visual flow dynamics and bubble size measurements inside the impeller channel. Experimental data was acquired utilizing two types of tests (surging test and bubble diameter measurement test) to completely evaluate the Pump behavior at different operational conditions. A similarity analysis performed for single-phase flow inside the Pump concluded that viscosity effects are negligible compared to the centrifugal field effects for rotational speeds higher than 600 rpm. Therefore, the two-phase flow tests were performed for rotational speeds of 600, 900, 1200, and 1500 rpm. Results showed formation of a large gas pocket at the Pump intake during surging conditions.© 2009 ASME
J R Mcdonald - One of the best experts on this subject based on the ideXlab platform.
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design and evaluation of a preprototype hybrid fiber optic voltage sensor for a remotely interrogated condition monitoring system
2005Co-Authors: Pawel Niewczas, L Dziuda, Grzegorz Fusiek, J R McdonaldAbstract:In this paper, we give details of the design and laboratory evaluation of the preprototype hybrid fiber Bragg grating piezoelectric voltage sensor for a remotely interrogated condition monitoring system, such as the measurement system used for monitoring of electrical Submersible Pump (ESP) motors. The proposed sensor design is directed toward the upper voltage rating (5 kV) of ESP motors.
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hybrid fiber optic voltage sensor for remote monitoring of electrical Submersible Pump motors
2005Co-Authors: L Dziuda, Pawel Niewczas, Grzegorz Fusiek, J R McdonaldAbstract:We report on the design and experimental evaluation of the hybrid fiber Bragg grating (FBG) piezoelectric voltage sensor developed specifically for remote monitoring of electrical Submersible Pump (ESP) motors. Unlike a previously reported transducer based on a single piezo- electric element, the voltage rating of the presented device could be as low as 500 V due to the use of a multilayer piezoelectric stack as the primary voltage-to-strain transducer. This enables the use of such sen- sors across a wider range of ESP applications, which often have subki- lovolt voltage ratings. In addition to the design details, we present details of the full characterization of the device, including the hysteresis and temperature-dependence characteristics and discuss ways of eliminating or reducing these effects. We also demonstrate that the sensor can be used to simultaneously measure voltage and temperature. © 2005 Society
