scholarly journals Study of GLR and Inlet Velocity on Hydrocyclone for Fracturing Flow-Back Fluids

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Bing Liu ◽  
Huajian Wang ◽  
Luncao Li ◽  
Zhenjiang Zhao ◽  
Liping Xu ◽  
...  
Keyword(s):  
Particle Size ◽  
Separation Efficiency ◽  
Tangential Velocity ◽  
Reynolds Stress Model ◽  
Optimum Range ◽  
Inlet Velocity ◽  
Split Ratio ◽  
Vortex Finder ◽  
Computational Fluid Dynamics Cfd ◽  
Solid Liquid

In this work, based on the Reynolds stress model (RSM) of the computational fluid dynamics (CFD) software Fluent and experimental method, the velocity field, pressure characteristics, split ratio, and separation efficiency of the hydrocyclone are analyzed under different gas-liquid ratios (GLRs). For the inlet velocity, the lower limit is ascertained by the flow field stability, the upper limit is largely determined by the energy consumption, and the optimum range is 4 m/s to 10 m/s. Within the optimum range, the peak value of tangential velocity increases while the GLR increases, whereas the pressure and pressure drop decrease. With the increase in the GLR, the axial velocity decreases, and the locus of zero vertical velocity shifts inward. The increase in the GLR causes more gas to collect at the vortex finder, which hinders the discharge of the solid-liquid mixture from the overflow, and the larger the GLR, the faster the decrease in the split ratio. The separation efficiency of particles with a particle size of 15 μm is increased by 6.75%, and the separation efficiency of particles with a particle size of 30 μm is increased by 0.57%. Meanwhile, the separation efficiency is increased by 2.43%, and the cut size d50 is reduced as the GLR increases.

Computational Fluid Dynamics Applied to Bradley Hydrocyclones

2006 ◽  
Vol 530-531 ◽  
pp. 376-381 ◽  
Author(s):  
Luiz Gustavo Martins Vieira ◽  
João Jorge Ribeiro Damasceno ◽  
Marcos A.S. Barrozo
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Fluid Model ◽  
Reynolds Stress Model ◽  
Operational Conditions ◽  
Air Core ◽  
Volume Of Fluid Model ◽  
Computational Fluid Dynamics Cfd ◽  
Geometric Variables ◽  
Solid Liquid

Hydrocyclones are centrifugal devices employed on the solid-liquid and liquid-liquid separation. The operation and building of these devices are relatively simple, however the flow inside them is totally complex and its prediction is very difficult. The fluid moves on all possible directions (axial, radial and swirl), the effects of turbulence can not negligible and an air core along the center line of the hydrocyclone can appear when the operational conditions are favorable. For that reason, the most models that are used to predict the hydrocyclone performance are empirical and require the collection of the main operational and geometric variables in order to validate them. This work objectified to apply Computational Fluid Dynamics (CFD) on Bradley Hydrocyclone and compare the results from this technique to empirical models. The numerical simulation was made in a computational code called Fluent® that solves the transport equation by finite volume technique. The turbulence was described by Reynolds Stress Model (RSM) and the liquid-gas interface was treated by Volume of Fluid Model (VOF). In agreement with the results from the simulation, it was possible to predict the internal profiles of velocity, pressure, air core, particle trajectories, efficiencies, pressure drop and underflow-to-throughput ratio.

Numerical Simulation of Gas Flow in a Square Cyclone Separator With Double Inlets

2007 ◽  
Author(s):  
Bin Xiong ◽  
Xiaofeng Lu ◽  
R. S. Amano
Keyword(s):  
Pressure Drop ◽  
Flow Field ◽  
Gas Flow ◽  
Numerical Study ◽  
Reynolds Stress Model ◽  
Cyclone Separator ◽  
Stress Model ◽  
Inlet Velocity ◽  
Vortex Finder ◽  
Flow Changes

This paper presents a numerical study of gas flow in a square cyclone separator with a double inlet. The turbulence of gas flow is computed by the use of the Reynolds stress model. The distribution of the flow field and pressure drop under different constructional details, which include changes of the shape, size and arrangement of the vortex finder are obtained. The computed results in the distributions of pressure in different sections are verified by comparison with those measured. We found that the center of the flow field is nearly on the geometric center of the cyclone. The flow fields show a feature of Rankine eddy, i.e., a strongly swirling region in the central part and a pseudo-free eddy region of weak swirling intensity near the cyclone wall. Local vortex exists at the corners where the flow changes their direction sharply, but it is less chaotic than in the general square cyclone with a single inlet. The flow field away from the outlet of the vortex finder is different from the Rankine eddy. The pressure-drop increases rapidly with the increase of the inlet velocity, and the pressure-drop increases with the decrease of the diameter of vortex finder and the increase of length of the vortex finder. The calculat ed results of this paper provide some guidance for the optimization of the square cyclone separator structure.

Comparison of Spherical and Non-Spherical Objects in Cyclonic and Uniaxial Flow Regimes

2018 ◽  
Vol 884 ◽  
pp. 93-104
Author(s):  
Thomas Archbold ◽  
James K. Carson
Keyword(s):  
Drag Coefficient ◽  
Separation Efficiency ◽  
Tangential Velocity ◽  
Orientation Angle ◽  
Particle Orientation ◽  
Cfd Simulations ◽  
Chestnut Shell ◽  
Pneumatic Separation ◽  
Vortex Finder ◽  
Shell Particles

This paper uses the Muschelknautz method to model the cyclone separation of chestnut shell and kernel fragments simulated as a square plate and sphere respectively. Because of the opposing geometry of the kernel and shell particles, a new framework is derived using CFD simulations to predict the drag coefficient of the shell particle as a function of orientation and Reynolds number. The drag coefficient of the shell is approximately proportional to the sine of the orientation angle, squared. Despite this, particle orientation remains relatively constant for all practical geometric and velocity parameters within a cyclone, as implied by the assumptions used in this paper. The results from the separation model show that the tangential velocity is almost 86 times greater than the radial velocity of the particle beneath the vortex finder. Consequently, the full frontal area of the particle is not exposed to the radial flow and the particles are not separated effectively by drag force. An experimental separation efficiency of 28.5% compared to an efficiency of 0% predicted by classical cyclone theory, indicates that the shell particles could be re-entrained at the base of the cyclone. This suggests that cyclones do not utilise the differences in drag between particles. The simulation of chestnut kernel and shell particles in a uniaxial flow field (such as occurs in pneumatic separation) shows that it is theoretically possible to achieve a significantly larger separation efficiency when compared to cyclones.

Computational Fluid Dynamics Applied to Bradley Hydrocyclones

2005 ◽  
Vol 498-499 ◽  
pp. 264-269
Author(s):  
Luiz Gustavo Martins Vieira ◽  
João Jorge Ribeiro Damasceno ◽  
Marcos A.S. Barrozo
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Fluid Model ◽  
Reynolds Stress Model ◽  
Operational Conditions ◽  
Air Core ◽  
Volume Of Fluid Model ◽  
Computational Fluid Dynamics Cfd ◽  
Geometric Variables ◽  
Solid Liquid

Hydrocyclones are centrifugal devices employed on the solid-liquid and liquid-liquid separation. The operation and building of these devices are relatively simple, however the flow inside them is totally complex and its prediction is very difficult. The fluid moves on all possible directions (axial, radial and swirl), the effects of turbulence can not negligible and an air core along the center line of the hydrocyclone can appear when the operational conditions are favorable. For that reason, the most models that are used to predict the hydrocyclone performance are empirical and require the collection of the main operational and geometric variables in order to validate them. This work objectified to apply Computational Fluid Dynamics (CFD) on Bradley Hydrocyclone and compare the results from this technique to empirical models. The numerical simulation was made in a computational code called Fluent® that solves the transport equation by finite volume technique. The turbulence was described by Reynolds Stress Model (RSM) and the liquid-gas interface was treated by Volume of Fluid Model (VOF). In agreement with the results from the simulation, it was possible to predict the internal profiles of velocity, pressure, air core, particle trajectories, efficiencies, pressure drop and underflow-to-throughput ratio.

Hydrocyclone Numerical Simulation and Separation Efficiency Optimization

2014 ◽  
Vol 670-671 ◽  
pp. 655-658 ◽  
Author(s):  
Xian Ming Sun ◽  
Lei Wei
Keyword(s):  
Flow Field ◽  
Wall Thickness ◽  
Volume Fraction ◽  
Separation Efficiency ◽  
Pipe Wall ◽  
Reynolds Stress Model ◽  
Pipe Wall Thickness ◽  
Inlet Velocity ◽  
Affective Factors ◽  
Overflow Pipe

For the hydrocyclone’ separation efficiency affects by many factors, this paper combined Reynolds stress model and SIMPLEC algorithm of Fluent software with orthogonal test to simulate hydrocyclone’s operating process and analysis the flow field. Different overflow pipe wall thickness values (4mm, 8mm, 12mm), volume fraction values (1%, 5%, 10%) and inlet velocities (3m/s, 4m/s, 5m/s) was considered as the separation efficiency affective factors. Results show that the overflow pipe wall thickness has greatest influence on separation efficiency. The inlet velocity is the second and the volume fraction value is the last. The optimal combination is the overflow pipe wall thickness value 8mm, the volume fraction 5% and the inlet velocity 5m/s. The overflow pipe wall thickness value increasing can decrease the turbulent kinetic energy and increase the stability of hydrocyclone flow field.

A CFD Study of Gas-Solid Flow in Cyclones With a Tangential Single Inlet and a Direct Asymmetrical Spiral Inlet

2009 ◽  
Author(s):  
Bin Xiong ◽  
R. S. Amano ◽  
Xiaofeng Lu ◽  
Yingfeng Ji
Keyword(s):  
Pressure Drop ◽  
Velocity Distribution ◽  
Gas Flow ◽  
Collection Efficiency ◽  
Tangential Velocity ◽  
Reynolds Stress Model ◽  
Lagrangian Model ◽  
Solid Flow ◽  
Computational Fluid Dynamics Cfd ◽  
Particle Paths

This work presents a computational fluid dynamics (CFD) calculation of gas-solid flow in cyclones with a conventional tangential single inlet (CTSI) and a direct symmetrical spiral inlet (DSSI) which was developed by Zhao et al [1]. The Reynolds stress model (RSM) has been employed to predict the gas flow field and particle paths are calculated with the stochastic Lagrangian model. The calculated grade collection efficiency and pressure drop have reasonable agreement with the experimental data. All results indicate that the DSSI has effect on significantly increasing collection efficiency with insignificantly increasing pressure drop. Compared with the CTSI cyclone, the DSSI cyclone has higher collection efficiency due to larger tangential velocity distribution, less short re-circuiting flow and shorter distance for particles to move to the wall. But the larger tangential velocity distribution lead to a little higher pressure drop of the cyclone with DSSI.

Effect of Feed-Flow Rate in a Solid-Liquid Hydrocyclone Based on Total Solid Recovery Equation

2017 ◽  
Vol 751 ◽  
pp. 173-179
Author(s):  
Pichai Soison ◽  
Pakpoom Supachart ◽  
Pratarn Wongsarivej
Keyword(s):  
Particle Size ◽  
Flow Rate ◽  
Concentration Ratio ◽  
Separation Efficiency ◽  
Total Solid ◽  
Feed Flow Rate ◽  
Solid Concentration ◽  
Flow Ratio ◽  
Flow Rates ◽  
Solid Liquid

Many studies of hydrocyclones have confirmed that increasing the feed-flow rate results in a higher separation efficiency. The purpose of this study was to investigate the separation efficiency for a 100 mm solid–liquid hydrocyclone with 1 and 2 wt% solid concentrations at feed-flow rates of 2, 3, 4, 5 and 6 m3/hr. The solid concentration and particle size distribution were analysed using drying–weighing and a particle-size analyser (Mastersizer 2000), respectively. The experimental results indicated that an increase in feed-flow rate from 2 to 4 m3/hr produced decreased separation efficiency. However, when the feed-flow rates increased from 4 to 6 m3/hr, the separation efficiency increased. Furthermore, the higher the feed-flow rate, the smaller the cut size. A novel separation efficiency equation in terms of the concentration ratio and flow ratio is also proposed.

Numerical Simulations of Gas-Liquid-Solid Flows in a Hydrocyclone Separator

2007 ◽  
Author(s):  
S. M. Musavian ◽  
A. F. Najafi
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Reynolds Stress ◽  
Separation Efficiency ◽  
Flow Behavior ◽  
Tangential Velocity ◽  
Reynolds Stress Model ◽  
Multiphase Model ◽  
Air Core ◽  
Cfd Method

The flow behavior in hydrocyclones is quite complex. The Computational Fluid Dynamics (CFD) method was used to simulate the flow fields inside a hydrocyclone in order to improve its separation efficiency. In the computational fluid dynamics study of hydrocyclones, the air-core dimension is a key to predicting the mass split between the underflow and overflow. In turn, the mass split influences the prediction of the size classification curve. Three models, the k–e model, the Reynolds stress model without considering air core and Reynolds stress turbulence model with VOF multiphase model for simulating aircore, were compared for the predictions of velocity, axial and tangential velocity distributions and separation proportion. The RSM with aircore simulation model, since it produces some detailed features of the turbulence and multi phase, is clearly closer in predicting the experimental data than the other two.

Numerical Simulation of Flow Field and Separation Efficiency of Inclined Cut-In Double-Inlet Cyclone

2012 ◽  
Vol 184-185 ◽  
pp. 341-347
Author(s):  
Cai Jin Wu ◽  
Zheng Fei Ma ◽  
Yong Yang
Keyword(s):  
Numerical Simulation ◽  
Pressure Drop ◽  
Flow Field ◽  
Axial Velocity ◽  
Separation Efficiency ◽  
Tangential Velocity ◽  
Reynolds Stress Model ◽  
Stress Model ◽  
Three Dimension ◽  
Inclined Angle

The three-dimension flow field and the separation efficiency of the inclined cut-in double-inlet cyclone were simulated numerically with Reynolds Stress Model (RSM). Numerical results show that the flow field nonsymmetry is improved in the inclined cut-in double-inlet cyclone and the swirl in the flow field was decreased greatly compared to that in the single-inlet cyclone. With the increase of inclined angle, both the tangential velocity and the axial velocity first increase and then decrease, reaching a peak at inclined 12 ° angle and at inclined 10 ° angle, respectively. The pressure drop in the inclined cut-in double-inlet cyclone increases first and then decreases with the increase of inclined angle, reaching a maximum far lower than that in the single-inlet cyclone, while the change of the radial velocity is not obvious. The separation efficiency of the inclined cut-in double-inlet cyclone could be effectively improved and the optimum inclined angle is 10 °.

scholarly journals Numerical investigation of the hydrocyclone vortex finder depth on separation efficiency

2021 ◽  
Vol 347 ◽  
pp. 00039
Author(s):  
Lesiba Mokonyama ◽  
Thokozani Justin Kunene ◽  
Lagouge Kwanda Tartibu
Keyword(s):  
Fluid Dynamics ◽  
Cfd Simulation ◽  
Fine Particles ◽  
Volume Fraction ◽  
Separation Efficiency ◽  
Cfd Simulations ◽  
Industrial Sectors ◽  
Air Core ◽  
Vortex Finder ◽  
Computational Fluid Dynamics Cfd

Hydrocyclones are devices used in numerous chemicals, food, and mineral-related industrial sectors for the separation of fine particles. A d50 mm hydrocyclone was modelled with the use of the Computational fluid dynamics (CFD) simulation, ANSYS® Fluent 2021 R1. The vortex finder depth was varied from 20 mm, 30 mm, and 35 mm to observe the effects of pressure drop and separation efficiency from a varied vortex finder depth and characteristics of the air core. The numerical methods validated the results observed from different parameters such as volume fraction characteristics based on CFD simulations. The tangential and axial velocities increased as the vortex finder length increased. It was found that as the depth of the vortex finder is increased, particle re-entrainment time in the underflow stream increases, and separation efficiency improved.

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