The Experts below are selected from a list of 114 Experts worldwide ranked by ideXlab platform
Wensheng Li - One of the best experts on this subject based on the ideXlab platform.
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Gas–liquid two-phase flow patterns in a pipeline–Riser system with an S-shaped Riser
International Journal of Multiphase Flow, 2013Co-Authors: Nailiang Li, Wensheng LiAbstract:Abstract In this work, experiments on flow patterns during air–water two-phase flow in a long pipeline–Riser system has been carried out. The test loop with 50 mm i.d. consists of a horizontal pipeline with 114 m in length, followed by a 16 m downward inclined section, and ended at an S-shaped flexible Riser. The inclination of the downward section varied from −2° to −5° from the horizontal. Liquid and gas superficial velocities ranged from 0.03 to 1.5 m/s, and 0.04 to 6.0 m/s, respectively. Based on the analysis of the pressure at the Riser Base and liquid holdup at the Riser top, the flow regimes observed were classified into four categories. In contrast with severe slugging in a vertical or catenary Riser where fluid blowout is initiated by gas penetration into the Riser Base, fluid blowout of severe slugging in an S-shaped Riser is induced by gas intrusion into the upper limb of the Riser. Flow pattern maps for each declination were generated Based on the experimental data. The region of severe slugging was found to be sensitive to pipeline inclination. An existing model for the stability of steady state operation was modified. The modified model was tested against our experimental results. An excellent agreement between the experimental data and the predictions was obtained.
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Gas-liquid two-phase severe slugging in a pipeline-Riser system with S-shaped flexible Riser: Experiments and modeling
2013Co-Authors: Nailiang Li, Wensheng LiAbstract:The objective of the present work is to investigate the air-water two-phase flow patterns in pipeline-Riser system with an S-shaped flexible Riser. The test loop with 50 mm ID consists of a horizontal pipeline with 114 m in length, a downward inclined section with 16 m in length, and an S-shaped flexible Riser with 24 m in height when downward section inclined at −2° with respective to the horizontal. The inclination angle of the downward section varied from −2° to −5°. The liquid superficial velocity ranged from 0.03 to 1.5 m/s, and the gas superficial velocity from 0.4 to 6.0 m/s. Identification and characterization of flow regimes were attained by pressure at Riser-Base and liquid holdup at Riser top. Severe slugging I, severe slugging II, transition flow and stable flows are observed to exist. Flow pattern maps for each declination are presented and the transition criteria are proposed. It's found that as higher liquid and gas velocity is required for the transition of the flow in the pipeline from st...
Matthieu Minguez - One of the best experts on this subject based on the ideXlab platform.
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Riser Base jumper slugging analysis by cfd simulations
ASME 2013 32nd International Conference on Ocean Offshore and Arctic Engineering, 2013Co-Authors: Maya Bakkouch, Matthieu MinguezAbstract:Slugging is one of the operational hazards of subsea pipelines associated with the transportation of multiphase fluids. Such phenomenon can results in cyclic loading in the lines, leading to fatigue damage or high stress (possible strength concern) that need to be considered in the design process. However, there is a real lack in the literature of clear guidance addressing the way of investigation of such possible Flow Induced Vibration (FIV) issue.One solution is to perform Fluid Structure Interaction (FSI) analysis. However, for this purpose, it appears fundamental to recover at the best the main flow features that develop in characteristic piping systems. Depending on the flow conditions, on the line path configuration, slug can be disturbed, dissociated and consequently results in multi-scale flow that could become an additional source of fatigue. Riser Base Jumper (RBJ) in M-shape configuration, due to its complex geometry can be prone to such multi scale-flow and should be consequently treated with particular attention.The proposed paper aims to improve the understanding of the main flow features that accompany slug flow in a RBJ. It is proposed to use Computational Multiphase Fluid Dynamic (CMFD) to this end. The main objective of the analysis is to characterise at the best the different expected pressure variations and the related excitation frequencies.Copyright © 2013 by ASME
Nailiang Li - One of the best experts on this subject based on the ideXlab platform.
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Gas–liquid two-phase flow patterns in a pipeline–Riser system with an S-shaped Riser
International Journal of Multiphase Flow, 2013Co-Authors: Nailiang Li, Wensheng LiAbstract:Abstract In this work, experiments on flow patterns during air–water two-phase flow in a long pipeline–Riser system has been carried out. The test loop with 50 mm i.d. consists of a horizontal pipeline with 114 m in length, followed by a 16 m downward inclined section, and ended at an S-shaped flexible Riser. The inclination of the downward section varied from −2° to −5° from the horizontal. Liquid and gas superficial velocities ranged from 0.03 to 1.5 m/s, and 0.04 to 6.0 m/s, respectively. Based on the analysis of the pressure at the Riser Base and liquid holdup at the Riser top, the flow regimes observed were classified into four categories. In contrast with severe slugging in a vertical or catenary Riser where fluid blowout is initiated by gas penetration into the Riser Base, fluid blowout of severe slugging in an S-shaped Riser is induced by gas intrusion into the upper limb of the Riser. Flow pattern maps for each declination were generated Based on the experimental data. The region of severe slugging was found to be sensitive to pipeline inclination. An existing model for the stability of steady state operation was modified. The modified model was tested against our experimental results. An excellent agreement between the experimental data and the predictions was obtained.
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Gas-liquid two-phase severe slugging in a pipeline-Riser system with S-shaped flexible Riser: Experiments and modeling
2013Co-Authors: Nailiang Li, Wensheng LiAbstract:The objective of the present work is to investigate the air-water two-phase flow patterns in pipeline-Riser system with an S-shaped flexible Riser. The test loop with 50 mm ID consists of a horizontal pipeline with 114 m in length, a downward inclined section with 16 m in length, and an S-shaped flexible Riser with 24 m in height when downward section inclined at −2° with respective to the horizontal. The inclination angle of the downward section varied from −2° to −5°. The liquid superficial velocity ranged from 0.03 to 1.5 m/s, and the gas superficial velocity from 0.4 to 6.0 m/s. Identification and characterization of flow regimes were attained by pressure at Riser-Base and liquid holdup at Riser top. Severe slugging I, severe slugging II, transition flow and stable flows are observed to exist. Flow pattern maps for each declination are presented and the transition criteria are proposed. It's found that as higher liquid and gas velocity is required for the transition of the flow in the pipeline from st...
Maya Bakkouch - One of the best experts on this subject based on the ideXlab platform.
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Riser Base jumper slugging analysis by cfd simulations
ASME 2013 32nd International Conference on Ocean Offshore and Arctic Engineering, 2013Co-Authors: Maya Bakkouch, Matthieu MinguezAbstract:Slugging is one of the operational hazards of subsea pipelines associated with the transportation of multiphase fluids. Such phenomenon can results in cyclic loading in the lines, leading to fatigue damage or high stress (possible strength concern) that need to be considered in the design process. However, there is a real lack in the literature of clear guidance addressing the way of investigation of such possible Flow Induced Vibration (FIV) issue.One solution is to perform Fluid Structure Interaction (FSI) analysis. However, for this purpose, it appears fundamental to recover at the best the main flow features that develop in characteristic piping systems. Depending on the flow conditions, on the line path configuration, slug can be disturbed, dissociated and consequently results in multi-scale flow that could become an additional source of fatigue. Riser Base Jumper (RBJ) in M-shape configuration, due to its complex geometry can be prone to such multi scale-flow and should be consequently treated with particular attention.The proposed paper aims to improve the understanding of the main flow features that accompany slug flow in a RBJ. It is proposed to use Computational Multiphase Fluid Dynamic (CMFD) to this end. The main objective of the analysis is to characterise at the best the different expected pressure variations and the related excitation frequencies.Copyright © 2013 by ASME
Hoi Yeung - One of the best experts on this subject based on the ideXlab platform.
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Experimental study on severe slugging mitigation by applying wavy pipes
Chemical Engineering Research & Design, 2020Co-Authors: Lanchang Xing, Hoi Yeung, Joseph ShenAbstract:Wavy pipes were installed in the pipeline for mitigating severe slugging in pipeline/Riser systems. Experimental results have revealed that: with a wavy pipe applied, the operating region of severe slugging is reduced; the severity of severe slugging and oscillation flow is mitigated; the wavy pipe performs better with its outlet located upstream of the Riser Base. The wavy pipe is essentially reducing the slug length. For severe slugging the wavy pipe works by accelerating the movement of the gas in the pipeline to the Riser Base; for the oscillation flow it works by mixing the gas/liquid two phases.
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Pattern recognition techniques for horizontal and vertically upward multiphase flow measurement
2012Co-Authors: Tesi I. M. Arubi, Hoi YeungAbstract:The oil and gas industry need for high performing and low cost multiphase meters is ever more justified given the rapid depletion of conventional oil reserves that has led oil companies to develop smaller and marginal fields and reservoirs in remote locations and deep offshore, thereby placing great demands for compact and more cost effective solutions of on-line continuous multiphase flow measurement for well testing, production monitoring, production optimisation, process control and automation. The pattern recognition approach for clamp-on multiphase measurement employed in this study provides one means for meeting this need. High speed caesium-137 radioisotope-Based densitometers were installed vertically at the top of a 50.8mm and 101.6mm Riser as well as horizontally at the Riser Base in the Cranfield University multiphase flow test facility. A comprehensive experimental campaign comprising flow conditions typical of operating conditions found in the Petroleum Industry was conducted. The application...
