CFD Investigation of the Effect of Viscosity on a Three-Stage Electric Submersible Pump

2014 ◽  
Author(s):  
Henrique Stel ◽  
Thiago Sirino ◽  
Pamella R. Prohmann ◽  
Francisco Ponce ◽  
Sergio Chiva ◽  
...  
Keyword(s):  
Performance Degradation ◽  
Operating Conditions ◽  
Design Flow ◽  
Fluid Viscosity ◽  
Viscous Oil ◽  
Three Stages ◽  
Multistage Pump ◽  
Working Out ◽  
Electric Submersible Pump ◽  
Good Agreement

Electric Submersible Pumps (ESP’s) are multistage pump arrangements used in offshore petroleum production. Most of their applications are subject to viscous oil pumping, which causes performance degradation with respect to the regular service with water and changes some characteristics related to the flow dynamics inside the pump. The purpose of this work is to use CFD to investigate numerically the flow in a semi-axial type ESP with three stages operating with fluids of different viscosities. Both design and off-design flow rates are simulated, as well as different impeller rotation speeds. Head curves of the ESP for these cases are compared with experimental data and show good agreement. The importance of considering more than a single stage when studying ESP’s is discussed. The flow fields inside the pump channels for different operating conditions are compared, showing for instance that the flow is not always blade-oriented at the best efficiency point for service with fluids more viscous than water. The effect of the fluid viscosity and the rotation speed on the performance degradation is also explored. In addition, dimensional analysis is used in favor of a better understanding on how the pump performance degrades when working out of the design figure.

CFD Evaluation of Solid Particles Erosion in Curved Ducts

2010 ◽  
Vol 132 (7) ◽  
Author(s):  
Samy M. El-Behery ◽  
Mofreh H. Hamed ◽  
K. A. Ibrahim ◽  
M. A. El-Kadi
Keyword(s):  
Present Model ◽  
Penetration Rate ◽  
Operating Conditions ◽  
Solid Particles ◽  
Erosion Prediction ◽  
Loading Ratio ◽  
Three Stages ◽  
Maximum Penetration ◽  
Curved Ducts ◽  
Good Agreement

This paper investigates numerically the erosion phenomenon that occurs in 90 deg and 180 deg curved ducts. The erosion prediction model comprises from three stages: flow modeling, particle tracking, and erosion calculations. The proposed three stages of the present model are tested and validated. Comparisons between predicted penetration rate and published experimental data show a good agreement. The effects of bend orientation, inlet gas velocity, bend dimensions, loading ratio, and particle size on the penetration rate are also simulated. In addition, based on many predictions of erosion rate results, new CFD based correlations are developed for the maximum penetration rate and its location. These correlations can be used to predict the bend lifetime for particular operating conditions.

Gas Cooling and Humidification: Design of Packed Towers from Small-Scale Tests

1950 ◽  
Vol 163 (1) ◽  
pp. 41-53 ◽  
Author(s):  
W. F. Carey ◽  
G. J. Williamson
Keyword(s):  
Operating Conditions ◽  
Total Heat ◽  
Small Scale ◽  
Water Cooling ◽  
Packed Tower ◽  
Simple Method ◽  
Worked Example ◽  
Gas Cooling ◽  
Heat Method ◽  
Working Out

On plants in which gases are processed, the gases are often brought into direct contact with water—usually in packed towers. The purpose may be to cool a hot gas, to increase the humidity of a gas, or, in the well-known special case of water-cooling towers, to cool water by contact with atmospheric air. These processes involve simultaneous transfers of sensible heat and water vapour, and existing methods of analysis are complex and laborious, except for the cooling of water, for which Merkel's total-heat method has long been available. Merkel's approximate solution offers the engineer a simple method of working out, for any operating conditions, the amount of heat transferred and the “driving force” available for transferring it. The present paper generalizes the total-heat method and, with a permissible sacrifice in accuracy, preserves the essential simplicity of the water-cooling treatment for gas-cooling and humidification processes. To complete the design of a packed tower, a knowledge is required of the characteristics of the packing. Information obtained in small towers is given for a number of packings, and a worked example shows how to apply the method of treatment, and the packing data presented, to the design of a large plant tower.

A New Heat Transfer Correlation for Supercritical RP-3 Flowing in Vertical Tubes

2017 ◽  
Author(s):  
Longyun Wang ◽  
Zhi Tao ◽  
Jianqin Zhu ◽  
Haiwang Li ◽  
Zeyuan Cheng
Keyword(s):  
Heat Transfer ◽  
Influence Factors ◽  
Hydrocarbon Fuel ◽  
Operating Conditions ◽  
Major Influence ◽  
Absolute Deviation ◽  
New Correlation ◽  
Vertical Tubes ◽  
Correction Terms ◽  
Good Agreement

A new empirical correlation for upward flowing supercritical aviation kerosene RP-3 in the vertical tubes is proposed. In order to obtain the database, numerical simulation with a four-component surrogate model on RP-3 and LS low Reynolds turbulence model in vertical circular tube has been performed. Tubes of diameter 2mm to 10mm are studied and operating conditions cover pressure from 3MPa to 6MPa. Heat flux is 500KW/m2, mass flow rate is 700kg/(m2·s). The numerical results on wall temperature distribution under various conditions are compared with experimental data and a good agreement is achieved. The existing correlations are summarized and classified into three categories. Three representative correlations of each category are selected out to evaluate the applicability in heat transfer of supercritical RP-3. The result shows that correlations concluded from water and carbon-dioxide do not perform well in predicting heat transfer of hydrocarbon fuel. The mean absolute deviation of them is up to 20% and predict about 80% of the entire database within 30% error bands. So a new correlation which is applicable to different working conditions for supercritical RP-3 is put forward. Gnielinski type has been adapted as the basis of the new correlation for its higher accuracy. In consideration of major influence factors of supercritical heat transfer, correction terms of density and buoyancy effect are added in. The new correlation has a MAD of 9.26%, predicting 90.6% of the entire database within ±15% error bands. The comparisons validate the applicability of the new correlation.

Jetting of viscous droplets from cavitation-induced Rayleigh–Taylor instability

2018 ◽  
Vol 846 ◽  
pp. 916-943 ◽  
Author(s):  
Qingyun Zeng ◽  
Silvestre Roberto Gonzalez-Avila ◽  
Sophie Ten Voorde ◽  
Claus-Dieter Ohl
Keyword(s):  
Bubble Dynamics ◽  
Stokes Equations ◽  
Droplet Surface ◽  
Taylor Instability ◽  
Bubble Collapse ◽  
Fluid Viscosity ◽  
Analytic Model ◽  
Radial Acceleration ◽  
Rayleigh Taylor Instability ◽  
Good Agreement

Liquid jetting and fragmentation are important in many industrial and medical applications. Here, we study the jetting from the surface of single liquid droplets undergoing internal volume oscillations. This is accomplished by an explosively expanding and collapsing vapour bubble within the droplet. We observe jets emerging from the droplet surface, which pinch off into finer secondary droplets. The jetting is excited by the spherical Rayleigh–Taylor instability where the radial acceleration is due to the oscillation of an internal bubble. We study this jetting and the effect of fluid viscosity experimentally and numerically. Experiments are carried out by levitating the droplet in an acoustic trap and generating a laser-induced cavitation bubble near the centre of the droplet. On the simulation side, the volume of fluid method (OpenFOAM) solves the compressible Navier–Stokes equations while accounting for surface tension and viscosity. Both two-dimensional (2-D) axisymmetric and 3-D simulations are performed and show good agreement with each other and the experimental observation. While the axisymmetric simulation reveals how the bubble dynamics results destabilizes the interface, only the 3-D simulation computes the geometrically correct slender jets. Overall, experiments and simulations show good agreement for the bubble dynamics, the onset of disturbances and the rapid ejection of filaments after bubble collapse. Additionally, an analytic model for the droplet surface perturbation growth is developed based on the spherical Rayleigh–Taylor instability analysis, which allows us to evaluate the surface stability over a large parameter space. The analytic model predicts correctly the onset of jetting as a function of Reynolds number and normalized internal bubble energy.

Numerical Analysis of the Flow Inside a Centrifugal Compressor’s Vaneless Diffuser and Volute

2001 ◽  
Author(s):  
Hooman Rezaei ◽  
Abraham Engeda ◽  
Paul Haley
Keyword(s):  
Experimental Data ◽  
Numerical Analysis ◽  
Mass Flow ◽  
Operating Conditions ◽  
Vaneless Diffuser ◽  
Flow Angle ◽  
Flow Rates ◽  
Mass Flow Rates ◽  
Minimum Medium ◽  
Good Agreement

Abstract The objective of this work was to perform numerical analysis of the flow inside a modified single stage CVHF 1280 Trane centrifugal compressor’s vaneless diffuser and volute. Gambit was utilized to read the casing geometry and generating the vaneless diffuser. An unstructured mesh was generated for the path from vaneless diffuser inlet to conic diffuser outlet. At the same time a meanline analysis was performed corresponding to speeds and mass flow rates of the experimental data in order to obtain the absolute velocity and flow angle leaving the impeller for those operating conditions. These values and experimental data were used as inlet and outlet boundary conditions for the simulations. Simulations were performed in Fluent 5.0 for three speeds of 2000, 3000 and 3497 RPM and mass flow rates of minimum, medium and maximum. Results are in good agreement with the experimental ones and present the flow structures inside the vaneless diffuser and volute.

Thermal Analysis of Stacked Ni-MH Battery

1999 ◽  
Author(s):  
Katsumi Hisano ◽  
Hideo Iwasaki ◽  
Masaru Ishizuka ◽  
Tetsuya Yamane
Keyword(s):  
Thermal Analysis ◽  
Numerical Analysis ◽  
Temperature Rise ◽  
Test Case ◽  
Charge Retention ◽  
Calculated Temperature ◽  
Computational Load ◽  
Three Stages ◽  
Mh Battery ◽  
Good Agreement

Abstract Numerical analysis was carried out to evaluate the temperature rise and charge retention of Ni-MH batteries as pallet loads. In this paper, thermal analysis of pallet loads which contain 2400 mAh Ni-MH batteries is considered as a test case. To reduce computational load, thermal analysis was performed in three stages. Measured and calculated temperature rise of the load showed good agreement, and it can be observed that there exists an appropriate charge retention of the battery to sustain high retention during transportation.

A Confrontation of Lattice Boltzmann, Finite Difference and Taguchi Experimental Design Results for Optimizing Plasma Spraying Operating Conditions Toward Deposit Requirements

2017 ◽  
Vol 6 (4) ◽  
pp. 16-34 ◽  
Author(s):  
Ridha Djebali
Keyword(s):  
Experimental Design ◽  
Plasma Spraying ◽  
Lattice Boltzmann ◽  
Operating Conditions ◽  
Taguchi Experimental Design ◽  
Confirmation Test ◽  
Boltzmann Method ◽  
Impact Characteristics ◽  
Plasma Spraying Process ◽  
Good Agreement

The aim of the present work is the confrontation of three numerical techniques results to optimize the operating conditions of thermal plasma spraying process. The Lattice Boltzmann method (LBM) is used to scrutinize dispersion effects of injection parameters on droplet impact characteristics when impacting substrate. The validation of the developed model shows good agreement with former findings. The results of spraying Zirconia particles give the values Kmin=88.2, Kmax=367.4, Kmean=273.8 and a standard deviation of 48.0 for the Sommerfeld number. The Taguchi experimental design study is conducted for five operating parameters of two levels. The ensuing retained factors combination give Kmean=258.9. To assess drawn conclusions, confirmation test was performed using the Jets&Poudres software. The results show that the prior way is to coat and particles of dp< 40.3 µm have evaporated, particles 40.3 = dp = 49 µm are fully molten and all particles of dp = 71.9 µm arrive fully solid.

A model for the vibrator–ground coupling vibration and the dynamic responses under excitation of sweep signal

2019 ◽  
Vol 22 (8) ◽  
pp. 1855-1866 ◽  
Author(s):  
Gang Li ◽  
Zhi-Qiang Huang ◽  
Zhang-Hua Lian ◽  
Lei Hao
Keyword(s):  
Dynamic Stiffness ◽  
Low Frequency ◽  
Dynamic Responses ◽  
Coupling Vibration ◽  
Lower Velocity ◽  
Dynamic Damping ◽  
Velocity Response ◽  
Cell Test ◽  
Three Stages ◽  
Good Agreement

To analyze the behavior of the vibrator–ground coupling vibration, a model containing equivalent dynamic stiffness and equivalent dynamic damping to describe the interaction between the vibrator and the ground is established based on half-space theory. According to load cell test, this model shows a good agreement with the experimental data. Dynamic responses of the structure are analyzed on displacement, velocity, acceleration, and ground force. Results show that the stroke and pump displacement are main constraints that limit the bandwidth of vibrator toward low frequency, and the stroke of conventional vibrator is not long enough to achieve lower frequency. Analysis of velocity response indicates that with the increase of frequency, a larger mass results in a lower velocity under external force. The influence of the ground acting on the baseplate is limited, and the acceleration of the baseplate is determined by its own mass beyond 80 Hz. Analysis of ground force shows that the response of the structure can be divided into three stages. The reaction mass, the baseplate, and the ground play different roles in dominating the ground force at different frequency bands.

scholarly journals Dispersed phase hold-up and characteristic velocity in a pulsed packed extraction column

2012 ◽  
Vol 18 (2) ◽  
pp. 255-262 ◽  
Author(s):  
Mehdi Asadollahzadeh ◽  
Jaber Safdari ◽  
Ali Haghighi-Asl ◽  
Meisam Torab-Mostaedi
Keyword(s):  
Physical Properties ◽  
Packed Column ◽  
Operating Conditions ◽  
Empirical Correlation ◽  
Extraction Column ◽  
Dispersed Phase ◽  
Characteristic Velocity ◽  
Operating Variables ◽  
Liquid Systems ◽  
Good Agreement

Dispersed phase hold-up has been measured in a 76.2 mm diameter pulsed packed column for four different liquid-liquid systems. The effects of pulsation intensity, phase ratio, and packing characteristic on the hold-up have been investigated under a variety of operating conditions. The dispersed phase axial hold-up shows a strong non-uniformity, depending on the operating conditions. The results indicated that the characteristic velocity approach is applicable to this type of extraction column for analysis of hold-up. An empirical correlation is derived for prediction of the hold-up in terms of operating variables, physical properties of the systems, and packing geometry. Good agreement between prediction and experiments was observed for all investigated operating conditions.

Effect of IC Engine Operating Conditions on Combustion and Emission Characteristics

1993 ◽  
Vol 115 (4) ◽  
pp. 694-701 ◽  
Author(s):  
Jiang Lu ◽  
Ashwani K. Gupta ◽  
Eugene L. Keating
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Emission Characteristics ◽  
Ic Engine ◽  
Pollutants Emission ◽  
Good Agreement

Numerical simulation of flow, combustion, heat release rate, and pollutants emission characteristics have been obtained using a single cylinder internal combustion engine operating with propane as the fuel. The data show that for good agreement with experimental results on the peak pressure and the rate of pressure rise as a function of crank angle, spark ignition energy and local cylinder pressure must be properly modeled. The results obtained for NO and CO showed features which are qualitatively in good agreement and are similar to those reported in the literature for the chosen combustion chamber geometry. The results have shown that both the combustion chamber geometry and engine operating parameters affects the flame growth within the combustion chamber which subsequently affects the pollutants emission levels. The code employed the time marching procedure and solves the governing partial differential equations of multicomponent chemically reacting fluid flow by finite difference method. The numerical results provide a cost effective means of developing advanced internal combustion engine chamber geometry design that provides high efficiency and low pollution levels. It is expected that increased computational tools will be used in the future for enhancing our understanding of the detailed combustion process in internal combustion engines and all other energy conversion systems. Such detailed information is critical for the development of advanced methods for energy conservation and environmental pollution control.

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