Phase Split of Oil-Water Two-Phase Flows at a T-Junction with a Vertically Downward Branch

2012 ◽  
Vol 550-553 ◽  
pp. 2977-2980 ◽  
Author(s):  
Li Min Yang ◽  
Li Li Zhao ◽  
Yi Xin Leng
Keyword(s):  
Phase Separation ◽  
Flow Pattern ◽  
Separation Efficiency ◽  
Two Phase Flows ◽  
Two Phase ◽  
Inlet Flow ◽  
Segregated Flow ◽  
Oil Water ◽  
Water Cut ◽  
Mixture Velocity

A T-junction with a horizontal main pipe and a vertically downward branch was employed to investigate phase separation phenomenon of oil-water two-phase flows at two segregated flow patterns. Water and kerosene (density of 796 kg/m3) were chosen as the working fluids. The effects of inlet flow pattern, mixture velocity, and water cut on the phase separation were examined. The results show that the variation of the mixture velocity in the same inlet flow pattern has little influence on the phase split and the phase separation highly depends upon the inlet flow pattern. The lower the mixedness of the inlet flow, the higher the separation efficiency can be achieved. The higher the water cut, the lower the separation efficiency peak can reach.

Oil-Water Two-Phase Flows in Large-Diameter Pipelines

2001 ◽  
Vol 123 (4) ◽  
pp. 270-276 ◽  
Author(s):  
H. Shi ◽  
J. Cai ◽  
W. P. Jepson
Keyword(s):  
Mixed Layer ◽  
Large Diameter ◽  
Water Layer ◽  
Two Phase ◽  
Horizontal Pipe ◽  
Water Flows ◽  
Layer Velocity ◽  
Oil Water ◽  
Water Cut ◽  
Mixture Velocity

Two-phase oil-water flows in a 10-cm-dia horizontal pipe have been experimentally investigated to study the effect of surfactant on oil-water distributions. Results show that at input water cut of 20 percent and lower, the water layer velocity is lower than mixed layer velocity up to an input mixture velocity of 1.6 m/s. However, at input water cut of 40 percent and higher, the water layer velocity is lower than the mixed layer velocity up to an input mixture velocity of only 0.8 m/s. Oil and water are much easier to be mixed at the medium input water cuts between 40 and 60 percent. The addition of surfactant enhances the degree of mixing of oil-water flow. With an increase of surfactant concentration, the water layer disappears, oil and water start to mix at lower mixture velocity, and the homogeneous flow pattern was observed at much lower input mixture velocity. Also, the mixed layer occupies a much greater fraction of the pipe. These indicate that corrosion could be reduced at lower input superficial mixture velocity with surfactants in oil-water flows.

Measuring Flow Pattern Asymmetry of Oil-Water Two Phase Flows Using Multi-channel Rotating Electric Field Conductance Signals

2018 ◽  
Vol 74 (1) ◽  
pp. 25-41 ◽  
Author(s):  
Yuansheng He ◽  
Yingyu Ren ◽  
Yunfeng Han ◽  
Ningde Jin
Keyword(s):  
Electric Field ◽  
Flow Pattern ◽  
Cross Section ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Two Phase ◽  
Time Asymmetry ◽  
Pipe Cross Section ◽  
Multi Scale ◽  
Oil Water

AbstractThe present study is a report on the asymmetry of dispersed oil phase in vertical upward oil-water two phase flow. The multi-channel signals of the rotating electric field conductance sensor with eight electrodes are collected in a 20-mm inner diameter pipe, and typical images of low pattern are captured using a high speed camera. With the multi-channel rotating electric field conductance signals collected at pipe cross section, multi-scale time asymmetry (MSA) and an algorithm of multi-scale first-order difference scatter plot are employed to uncover the fluid dynamics of oil-water two phase flow. The results indicate that MSA can characterise the non-linear behaviours of oil-water two phase flow. Besides, the MSA analysis also beneficial for understanding the underlying inhomogeneous distribution of the flow pattern in different directions at pipe cross section.

A Four-Sector Conductance Method for Measuring and Characterizing Low-Velocity Oil–Water Two-Phase Flows

2016 ◽  
Vol 65 (7) ◽  
pp. 1690-1697 ◽  
Author(s):  
Zhongke Gao ◽  
Yuxuan Yang ◽  
Lusheng Zhai ◽  
Ningde Jin ◽  
Guanrong Chen
Keyword(s):  
Two Phase Flows ◽  
Low Velocity ◽  
Two Phase ◽  
Conductance Method ◽  
Oil Water

Ultrasonic method for measuring water holdup of low velocity and high-water-cut oil-water two-phase flow

2016 ◽  
Vol 13 (1) ◽  
pp. 179-193 ◽  
Author(s):  
An Zhao ◽  
Yun-Feng Han ◽  
Ying-Yu Ren ◽  
Lu-Sheng Zhai ◽  
Ning-De in
Keyword(s):  
Two Phase Flow ◽  
Ultrasonic Method ◽  
High Water ◽  
Phase Flow ◽  
Low Velocity ◽  
Two Phase ◽  
Oil Water ◽  
High Water Cut ◽  
Water Cut

Surrogate Models for Predicting the Performance of a Liquid-Liquid Cylindrical Cyclone Separator

2006 ◽  
Author(s):  
Jorge E. Pacheco ◽  
Miguel A. Reyes
Keyword(s):  
Flow Pattern ◽  
Mean Squared Error ◽  
Surrogate Models ◽  
Mechanistic Models ◽  
Water Mixture ◽  
Inlet Flow ◽  
Prediction Tools ◽  
Squared Error ◽  
Cylindrical Cyclone ◽  
Oil Water

Liquid-Liquid Cylindrical Cyclone (LLCC) separators are devices used in the petroleum industry to extract a portion of the water from the oil-water mixture obtained at the well. The oil-water mixture entering the separator is divided due to centrifugal and buoyancy forces in an upper (oil rich) exit and a bottom (water rich) exit. The advantages in size and cost compared with traditional vessel type static separators are significant. The use of LLCC separators has not been widespread due to the lack of proven performance prediction tools. Mechanistic models have been developed over the years as tools for predicting the behavior of these separators. These mechanistic models are highly dependent on the inlet flow pattern prediction. Thus, for each specific inlet flow pattern a sub-model has to be developed. The use of surrogate models will result in prediction tools that are accurate over a wider range of operational conditions. We propose in this study to use surrogate models based on a minimum-mean-squared-error method of spatial prediction known as Kriging. Kriging models have been used in different applications ranging from structural optimization, conceptual design, multidisciplinary design optimization to mechanical and biomedical engineering. These models have been developed for deterministic data. They are targeted for applications where the available information is limited due to the cost of the experiments or the time consumed in numerical simulations. We propose to use these models with a different framework so that they can manage information from replications. For the LLCC separator a two-stage surrogate model is built based on the Bayesian surrogate multistage approach, which allows for data to be incorporated as the model is improved. Cross validation mean squared error measurements are analyzed and the model obtained shows good predicting capabilities. These surrogate models are efficient and versatile predicting tools that do not require information about the physical phenomena that drives the separation process.

Evaluation of Flow Characteristics in an Oil-Water Separator Using Computational Fluid Dynamics

2020 ◽  
Author(s):  
Terry Potter ◽  
Tathagata Acharya
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Residence Time ◽  
Water Volume ◽  
Multiphase Model ◽  
Two Phase ◽  
Water Separator ◽  
Oil Water ◽  
Simulation Results ◽  
Water Cut

Abstract Multiphase separators on production platforms are among the first equipment through which well fluids flow. Based on functionality, multiphase separators can either be two-phase that separate oil from water, or three-phase that separate oil, natural gas, and water. Separator performances are often evaluated using mean residence time (MRT) of the hydrocarbon phase. MRT is defined as the amount of time a given phase stays inside the separator. On field, operators usually measure MRT as the ratio of active volume occupied by each phase to the phase volumetric flowrate. However, this method may involve significant errors as the oil-water interface height is obtained using level controllers and the volume occupied by each phase is calculated assuming the interface can be extrapolated from the weir back to the separator inlet. In this study, authors perform computational fluid dynamics (CFD) on a two-phase horizontal separator to evaluate MRT as a function of varying water volume flowrates (water-cut) in a mixture of water and oil. The authors use residence time distributions (RTD) to obtain MRT at each water-cut — a method that results in significantly more accurate results than the regular method used by operators. The numerical model is developed with commercial software package ANSYS Fluent. The code uses the Eulerian multiphase model along with the k-ε turbulence model. The simulation results show agreement with experiments performed by previous researchers. Additional simulations are performed to assess the effect of various separator internals on separator performance. Simulation results suggest that the model developed in this study can be used to predict performances of two-phase liquid-liquid separators with reasonable accuracy and will be useful towards their design to improve performances under various inlet flow conditions.

Experimental Investigation on Flow Patterns and Frictional Pressure Drop of Downward Air-Water Two-Phase Flow in Vertical Pipes

2013 ◽  
Author(s):  
Yuqing Xue ◽  
Huixiong Li ◽  
Tianyou Sheng ◽  
Changjiang Liao
Keyword(s):  
Pressure Drop ◽  
Flow Pattern ◽  
Oil Recovery ◽  
Two Phase Flow ◽  
Flow Patterns ◽  
Phase Flow ◽  
Vertical Pipe ◽  
Two Phase Flows ◽  
Two Phase ◽  
Frictional Pressure Drop

A large amount of air need be transported into the reservoir in the deep stratum to supply oxygen to some microbes in Microbial Enhanced Oil Recovery (MEOR). Air-water two-phase flows downward along vertical pipeline during the air transportation. Base on the experiment data described in this paper, the characteristics of air-water two phase flow patterns were investigated. The flow pattern map of air-water two phase flows in the pipe with inner diameter of 65 mm was drawn, criterions of flow pattern transition were discussed, and the dynamic signals of the pressure and the differential pressure of the two phase flow were recorded to characterize the three basic flow regimes indirectly. The frictional pressure drop of downward flow in vertical pipe must not be disregarded contrast with upward two phase flow in the vertical pipe because the buoyancy must be overcame when the gas flows downward along pipe, and there would be a maximum value of frictional when the flow pattern translated from slug flow to churn flow.

Sign in / Sign up

Export Citation Format

Share Document