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Despite their low efficiency compared with centrifugal pumps, jet pumps are highly reliable, robust equipment with modest maintenance, ideal for many applications, mainly in the oil & gas industry. Jet pumps are conventionally used to draw fluid from a storage tank in the petrochemical industry or as an artificial lift system to produce oil from a reservoir using energy from the primary fluid. The trunk lines in oil production systems can experience an unfavourable phenomenon due to the fluid's low velocities. In the case of transporting a heavy oil-water mixture with low flow velocities, it could promote oil and water stratification. Due to high viscosity, the stratified oil stick on the pipe,| causing a diameter reduction, resulting in a drop in fluids production and increased energy consumption. Given the virtue of jet pumps, this paper proposes using this equipment as an oil-water transfer pump as an alternative to expensive conventional multiphase pump systems. The jet pump will add fluid into the line, increase the fluid velocities, and promote the homogenous mixture of oil and water. Using ANSYS CFX, the effect of installing a jet pump in a conventional trunkline loop was analysed. Three jet pump configurations were simulated for different driving fluid pressures and compared against a traditional pipeline loop's performance. The first configuration shows a poor performance increasing only until 10% of handling fluids. Conversely, with the improved jet pump configurations rise of the fluid production by 30% has been obtained.

The internal flow behavior of an ESP handling dispersed oil-water and emulsion flows remains quite unexplored. Previous studies have focused either on the individual droplet dynamics or on a simplified and limited modelling of the ESP's global performance. Hence, this study seeks to implement and analyze the applicability of a more robust and far-reaching CFD-PBM model which maintains a reasonable computational expenditure. Good agreement with experimental data was attained by the Eulerian-PBM framework (

This article is the first part of a study which analyzes the performance and internal flow of an ESP when handling oil-water flow, focusing on the characterization of the two-phase flow/emulsions observed and their influence on the ESP’s global performance. The testing facility consisted of a four-stage ESP located in a closed-loop arrangement. W/O emulsions are formed at high oil fractions, due to the presence of surface-active compounds and small droplet sizes. At the inversion, an increase in the viscosity and shear-thinning characteristics of the emulsion is noticed. At higher water cuts, the emulsion’s microscopic structure is lost, transitioning to a dispersed two-phase flow. The head rise increased noticeably at the inversion point thanks to the shear-thinning trend observed. The ESP’s performance improves at higher water fractions due to lower viscosities with a shear-thinning nature. As the non-Newtonian behavior is lost, higher water cuts do not affect the pump’s operation.

Electrical Submersible Pumps (ESPs) are among the most common artificial lifting methods employed nowadays in the O&G industry. This work aims to carry out an exhaustive analysis of the performance and flow features of a multistage ESP when handling Shear-Thinning non-Newtonian fluids, which are commonly found in mature, heavy oil wells. Currently, no studies have been conducted for multistage centrifugal pumps operating under such conditions. In this study, water, two Newtonian oils of different viscosities, and two non-Newtonian fluids, consisting of two CMC solutions in water (0.5% and 1% w/w), were tested. The testing facility consisted of a four-stage ESP located in a closed-loop arrangement in which the flowrate could be freely manipulated. Experimental measurements were taken to determine the pressure rise and power consumption by the ESP's motor. The CFD model was validated against experimental data collected in this study. The CFD head rise was in excellent agreement against the experimental data for water, with MSE of 4.91%. Good agreement was also observed, with a slight overprediction, for the pump's efficiency, with an MSE of 10.6%. The non-Newtonian fluids best fitted the Cross viscosity model. CMC 0.5% obtained a 12% higher average head rise than that of CMC 1%, despite the latter exhibiting a more pronounced Shear-Thinning trend (higher Cross time constant). It was found that the non-Newtonian fluids tested out-performed, in terms of head rise, the Newtonian oils by an average of 23.5%, and 11.4% against the heavier and the lighter oil, respectively. This improved performance was observed despite the non-Newtonian range of effective viscosities being over one or more orders of magnitude higher than the oils' dynamic viscosities. Furthermore, it was noted that the pump's performance with both non-Newtonian fluids did not deteriorate as rapidly as it did for the viscous oils. This lead to a shift in the BEP towards higher flowrates for the non-Newtonian fluids. This observation was supported by the CFD effective viscosity profiles, which showed a decline in the viscosity as the flowrate increased. CFD proved to be a valuable tool to analyze and understand in depth the viscosity variations and flow features throughout the pump's domain and their connection with the global performance observed for the ESP.

This document shows a complete analysis the transportation of sugar particles by a pneumatic conveying station. This project shows an actual situation presenting in a food plant located in Aragua, Venezuela, where the sugar piping system suffers continuous obstructions. It was achieved an effective analysis of the phenomenon of solid-gas two-phase flow transport which involves a complex physics phenomenon. Two possible obstruction causes was studied: the high temperature at the blower exit that induces changes in the sugar properties caused by the working condition far from the designed operation condition, or the excessive friction losses, due to the system is working out of the dilute phase condition (optimal condition for the flow). The mathematical model described allowed to determine that the cause of the obstruction of the pipeline was the stick of the sugar to the internal wall, as consequence of this high temperature at the outlet of the blower.

Frequently, Two-phase flow occurs in petroleum industry. It takes place on production and transportation of oil and natural gas. Initially, the most common patterns for vertical flow are Bubble, Slug, Churn and Annular Flow. Then, for horizontal flow, the most common patterns are Stratified Smooth, Stratified Wavy, Elongated Bubble, Slug, Annular, Wavy Annular and Dispersed Bubble Flow. It is also known that after separation, each fluid is carried through pipes, so oil is moved long distances. However, as it is known, the oil energy diminishes on the way. For that reason, it is needed a pumping station for keeping the oil flow energy high for proper movement. Additionally, that fluid is transported through a network, so fittings are present, like elbows, “T” and “Y” junctions, and others. As known, on a piping network, the losses can be classified in two groups: large and localized. The former consists on losses due to wall roughness-fluid interaction. The latter is related with fittings. This study is focused on 45° “Y” junctions. The main purpose of this study is to simulate the fluid flow on a 45° “Y” junction, using a 0.1143 m diameter 2 m length pipe, in which a 0.0603 m diameter 1 m length pipe confluences, using oil-gas as the working fluid, considering Dispersed Bubble Pattern. It can be attributed a “K” flow loss coefficient for each path, from each entry to the exit of the junction. For the Two-Phase Flow, it was supposed a horizontal Dispersed Bubble Pattern, which takes place at very high liquid flow rates. So the liquid phase is the continuous phase, in which the gas phase is dispersed as discrete bubbles. Particularly three API Grades were considered for the oil, corresponding to three main types of continuous phase. For the numerical model, it was generated several non-structured grids for validation, using water as a fluid. Then the simulations were carried out, using non-homogenous model, with oil and gas, changing the gas void fraction, and the superficial velocities for gas and liquid. A commercial package was used for numerical calculations. It was encountered that changing the value of the referred variables, in some cases the exit pressure of the “Y” junction diminishes. For validation of the results, a literature model was used for comparing both “K” loss coefficients: numerically and from the bibliography. It is important to highlight that these results, permit to analyze a way of diminishing the fluid energy losses in a Two-Phase oil-gas piping network, particularly in 45° “Y” junctions which represents economically saving.Copyright © 2015 by ASME

This investigation assessed detailed characteristics of flow in diverging manifolds, for water and water-oil cases. A 3D Computational Fluid Dynamics (CFD) model of a distributing manifold was carried out. Numerical results showed good agreement with experimental values. Predicted pressure and velocity contours agree with theory, detailed 3D insight on present secondary flows and localized hydraulic losses was obtained, as well as effect on distribution of phases. Moreover, a 3D, multi-phase (oil-water) CFD model of a diverging manifold design, similar to those installed in separation units was conducted. The main pipe had 0.762 m (30 in) in diameter and 24 m in length, with 8 perforated pipes branching out. Branches had 0.305 m (12 in) in diameter and 12 m in length, with 312 holes per branch. Non-uniform outflow distributions were detected, as well as secondary flows. An alternate design was proposed. Numerical results show the new manifold design achieves uniform static pressure distribution across the entire main pipe, reducing secondary flows and hydraulic losses. Outflow distribution is also uniform, thus improving the performance of the separation unit.Copyright © 2014 by ASME

Growing energy demand requires reliable, safe and long-lasting production systems, including, according to the new legislation, periodic inspections of the pipelines. Currently, design of cleaning tools meant for oil lines, is largely based on experimental information. Big service companies and research centres, built the right tools for their operations, but questions still remain regarding the behaviour of these devices under different flow conditions. In recent years, advances in CFD have allowed to analyse complex phenomena in many industrial applications, participating in technology improvement. The present work proposes a novel 2D CFD methodology to simulate the pigging processes, considering the straight movement of a Pig through a pipeline with a two-phase flow: water-air and oil-gas. The algorithm deforms the grid and re meshes specific domain sections to account for Pig translation relative to the pipe. Three Pig models (Mandrel Pigs, Foam Pigs and Spherical Pigs) were simulated in a horizontal pipe under single-phase liquid flow conditions. Subsequently Pigs were simulated under two-phase flow air-water conditions. Pressure and velocities profiles inside the pipe, and pressure distributions around the Pig were obtained. The result helps to understand the flow behaviour during the pigging processes, providing additional insight on design and operation of these devices.

Cross Flow Turbines (CFT), also known as Banki or Ossberger turbines are broadly used in small scale hydropower generation. Easy construction and operation, low CAPEX and OPEX and fairly independent efficiency from flow rate are the main characteristics of the CFT. However, they also tend to have a modest efficiency (80%), hence they are not considered for large scale power plants. Previous work have focused on use of Internal Deflectors (ID) for CFT efficiency improvement. However experimental flow observation and characterization inside CFT is hard to achieve. This work proposes use of Computational Fluid Dynamic (CFD) tools as an aid in ID design. A transient regime, two-dimensional, numerical model of a CFT without any internal deflectors was carried out. Deviation from experimental results at BEP was close to 5%. CFT w/o ID results were used as ID design starting point. Parameters: Upper Blade Position and ID Length were defined and varied obtaining six different ID versions. Numerical models were carried out for evaluation of ID effect on CFT. CFT hydraulic efficiency improvement was achieved for all ID versions studied (range 0.5%–3%, average:1.9%). Output power was also augmented (range 0.3%–4%, average:2.5%)for all cases.Copyright © 2012 by ASME

Two-phase flow is an area of primary interest, particularly for the petroleum industry, where a fair amount of these kinds of flows can be found in the production of oil wells. This study refers to the evaluation of two-phase flow air– water through a horizontal pipe of 0.0508m (2in) diameter and 1.016m (40in) length. A 3D CFD approach was used for reproducing the behavior of the dispersed bubble, stratified smooth and slug flow in a horizontal pipe. The pressure drop and liquid holdup associated with it were estimated. Data of the superficial velocities of the liquid and gas were taken from the literature; and then many CFD simulations were carried out using different multiphase flow models. The results were validated with the available experimental data from the literature. For the case in which the liquid is the continuous phase and the gas behaves as the dispersed one, the results show that the bubble disperse flow behaves homogeneously. In these simulations, for a 0.01mm gas bubble diameter the pressure drop presented a deviation of 6.12% over that reported in the literature. For the liquid holdup value a difference of 0.001% was obtained. An inhomogeneous approach with the free surface model reproduced satisfactorily the stratified smooth behavior. In addition, the influences of increasing water superficial velocity on the energy losses and the liquid holdup were obtained. However, for the studied numerical domain, the slug flow pattern could not be reproduced. All these results above allowed us to establish the great applicability of CFD modeling in the problem resolution of two-phase flow in a horizontal pipe.