Effects of Rotation Speeds on Electrical Submersible Pump Performance under Two-Phase Flow

The effects of the wall shear stress on an Electrical Submersible Pump (ESP) was investigated in this paper. A CFD model in ANSYS Fluent was proposed to simulate actual single-phase and two-phase flow. The bottom hole pressure was minimized by utilizing the artificial lift methods. The flowing fluids in pumps and pipes causes shear stress on surface interacting. In multiphase flow application pump damages on head degradation as well as shear stress affects. The K-ω turbulence model and the multiphase Mixture approach with the sliding technique used to solve the Navier-Stokes equation. To study the effects of gas-liquid (air-water) flow on the ESP and the pump handle ability, the rotation speeds were varied while the other parameters were kept constant. The rotation speeds simulated were at 500, 900, 1500, 2000 and 2500 rpm meanwhile the water flow rate and gas flow rate were kept constant with 20 L/min and 1% fraction, respectively. The results obtained show that as the rotation speeds were increased, the less concentration of the bubbles were observed, moreover the wall shear stress (WSS) increases. Although, the wall shear stress in both single-phase and two-phase flow were tend to increase as the blades length increased, however for the single-phase flow the WSS was found higher in all the simulated rotational speeds.

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Two-Phase Flow in an Annular Channel With an Obstacle

Volume 3: Thermal-Hydraulics; Turbines, Generators, and Auxiliaries ◽

10.1115/icone20-power2012-54450 ◽

2012 ◽

Author(s):

O. N. Kashinsky ◽

P. D. Lobanov ◽

A. S. Kurdyumov ◽

N. A. Pribaturin

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Void Fraction ◽

Two Phase Flow ◽

Three Dimensional ◽

Annular Channel ◽

Electrochemical Technique ◽

Phase Flow ◽

Two Phase ◽

Wall Shear

Experimental study of gas-liquid two-phase flow in an annular channel is performed. The channel consisted of two coaxial tubes with the diameters of 42 and 20 mm. An obstacle covering a quarter of the channel section was placed in the channel to produce a strong three-dimensional disturbance of the flow. Gas-liquid flow was produced by injecting air bubbles at the channel entrance through a special mixer. Measurements of local wall shear stress are performed using an electrochemical technique. Measurements of time-averaged and fluctuational wall shear stress are performed at various points relative to the obstacle, this allowed to study the field of the hydrodynamic parameters of the flow. Local void fraction is measured using a conductivity probe which traversed across the channel. The distribution of local void fraction in the region downstream the obstacle is obtained. Increased values of local void fraction in the region close to the obstacle are detected. The experimental data obtained can be used for validation of existing and developing computer codes accounting for a 3-D structure of two-phase flows.

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Development of a Transient Mechanistic Two-Phase Flow Model for Wellbores

SPE Journal ◽

10.2118/142224-pa ◽

2012 ◽

Vol 17 (03) ◽

pp. 942-955 ◽

Cited By ~ 11

Author(s):

Mahdy Shirdel ◽

Kamy Sepehrnoori

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Two Phase Flow ◽

Fluid Model ◽

Flow Regimes ◽

Phase Flow ◽

Two Phase ◽

Wall Shear ◽

Two Fluid Model ◽

Two Fluid

Summary A great deal of research has been focused on transient two-phase flow in wellbores. However, there is lack of a comprehensive two-fluid model in the literature. In this paper, we present an implementation of a pseudo-compositional, thermal, fully implicit, transient two-fluid model for two-phase flow in wellbores. In this model, we solve gas/liquid mass balance, gas/liquid momentum balance, and two-phase energy balance equations to obtain five primary variables: liquid velocity, gas velocity, pressure, holdup, and temperature. This simulator can be used as a stand-alone code or can be used in conjunction with a reservoir simulator to mimic wellbore/reservoir dynamic interactions. In our model, we consider stratified, bubbly, intermittent, and annular flow regimes using appropriate closure relations for interphase and wall-shear stress terms in the momentum equations. In our simulation, we found that the interphase and wall-shear stress terms for different flow regimes can significantly affect the model's results. In addition, the interphase momentum transfer terms mainly influence the holdup value. The outcome of this research leads to a more accurate simulation of multiphase flow in the wellbore and pipes, which can be applied to the surface facility design, well-performance optimization, and wellbore damage estimation.

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Modeling Oscillatory Behavior of Electrical Submersible Pump Wells Under Two-Phase Flow Conditions

Journal of Energy Resources Technology ◽

10.1115/1.4028271 ◽

2014 ◽

Vol 136 (4) ◽

Cited By ~ 3

Author(s):

Rinaldo Antonio de Melo Vieira ◽

Mauricio Gargaglione Prado

Keyword(s):

Flow Rate ◽

Liquid Flow ◽

Two Phase Flow ◽

Liquid Flow Rate ◽

Oscillatory Behavior ◽

Phase Flow ◽

Submersible Pump ◽

Flow Conditions ◽

Two Phase ◽

Electrical Submersible Pump

The effect of free gas on electrical submersible pump (ESP) performance is well known. At a constant rotational speed and constant liquid flow rate, a small amount of gas causes a mild head reduction when compared to the single phase liquid head. However, at higher gas rates, a drastic reduction in the head is observed. This critical condition, known as the surging point, is a combination of liquid and gas flow rates that cause a maximum in the head performance curve. The first derivative of the head with respect to the liquid flow rate changes sign as the liquid flow rate crosses the surging point. In several works on ESP two-phase flow performance, production conditions to the left of the surging region are described or reported as unstable operational conditions. This paper reviews basic concepts on stability of dynamical systems and shows through simulation that ESP oscillatory behavior may result from two-phase flow conditions. A specific drift flux computation code was developed to simulate the dynamic behavior of ESP wells producing without packers.

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Development of a wall shear stress integral measurement and analysis system for two-phase flow boundary layers

Review of Scientific Instruments ◽

10.1063/1.2360887 ◽

2006 ◽

Vol 77 (10) ◽

pp. 105103 ◽

Cited By ~ 7

Author(s):

Elvis E. Dominguez-Ontiveros ◽

Carlos E. Estrada-Perez ◽

Javier Ortiz-Villafuerte ◽

Yassin A. Hassan

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Boundary Layers ◽

Two Phase Flow ◽

Phase Flow ◽

Two Phase ◽

Flow Boundary ◽

Measurement And Analysis ◽

Wall Shear ◽

Analysis System

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Wall shear stress measurements in vertical air-water annular two-phase flow

International Journal of Multiphase Flow ◽

10.1016/0301-9322(89)90003-7 ◽

1989 ◽

Vol 15 (3) ◽

pp. 307-325 ◽

Cited By ~ 23

Author(s):

A.H. Govan ◽

G.F. Hewitt ◽

D.G. Owen ◽

G. Burnett

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Two Phase Flow ◽

Phase Flow ◽

Two Phase ◽

Stress Measurements ◽

Wall Shear

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Numerical Study of Flow Dynamics in Human Eye Vitreous Chamber After Vitrectomy and Gas Tamponade

Volume 2: Fora ◽

10.1115/ajkfluids2015-26372 ◽

2015 ◽

Author(s):

Ali Yousefi ◽

Omid Abouali ◽

Ebrahim Ghoshtasbi Rad ◽

Goodarz Ahmadi

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Two Phase Flow ◽

Numerical Study ◽

Maximum Shear Stress ◽

Phase Flow ◽

Two Phase ◽

Human Eye ◽

Gas Tamponade ◽

Wall Shear

The purpose of this study is to evaluate the flow pattern and the fluid shear stress acting on the retinal wall in a human eye vitreous chamber after Vitrectomy and gas tamponade including the effect of saccadic eye movements. The correlation between the maximum shear stress induced on the retinal wall and the gas fill fraction (GF) and saccade amplitudes was investigated. In modeling the geometry of vitreous chamber cavity, the indentation of the lens was taken into account. The two-phase flow at the recovery phase of the operation was modeled numerically. Unsteady three-dimensional forms of continuity and Navier-Stokes equations were solved. Volume-of-fluid method was used to solve the two-phase flow in the eye. Saccadic motion of the eye was modeled using the dynamic mesh technique. The numerical model was validated by comparing the results with the available analytical solutions and experimental data for a spherical model. Then, numerical simulation was performed based on the deformed sphere configuration, representing a more realistic model of vitreous chamber cavity. The simulation results were compared with the available numerical studies for the spherical geometry. Then the wall shear stress on the retina was computed and compared for various gas fractions. The potential effect of wall shear stress on the retinal detachment and the need for post-operation posturing in all studied cases were discussed.

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