On the Accelerated Settling of Fine Particles in a Bidisperse Slurry

An estimation of increasing the volume average sedimentation velocity of fine particles in bidisperse suspension due to their capturing in the circulation zone formed in the laminar flow of incompressible viscous fluid around the spherical coarse particle is proposed. The estimation is important for an explanation of the nonmonotonic shape of the separation curve observed for hydrocyclones. The volume average sedimentation velocity is evaluated on the basis of a cellular model. The characteristic dimensions of the circulation zone are obtained on the basis of a numerical solution of Navier-Stokes equations. Furthermore, these calculations are used for modelling the fast sedimentation of fine particles during their cosedimentation in bidisperse suspension. It was found that the acceleration of sedimentation of fine particles is determined by the concentration of coarse particles in bidisperse suspension, and the sedimentation velocity of fine fraction is proportional to the square of the coarse and fine particle diameter ratio. The limitations of the proposed model are ascertained.

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A multi-moment finite volume method for incompressible Navier–Stokes equations on unstructured grids: Volume-average/point-value formulation

Journal of Computational Physics ◽

10.1016/j.jcp.2014.08.011 ◽

2014 ◽

Vol 277 ◽

pp. 138-162 ◽

Cited By ~ 35

Author(s):

Bin Xie ◽

Satoshi Ii ◽

Akio Ikebata ◽

Feng Xiao

Keyword(s):

Finite Volume Method ◽

Finite Volume ◽

Stokes Equations ◽

Unstructured Grids ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Volume Average ◽

Volume Method

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Hydrodynamic limit for the Vlasov-Navier-Stokes equations. Part II: Fine particles regime.

Indiana University Mathematics Journal ◽

10.1512/iumj.2004.53.2509 ◽

2004 ◽

Vol 53 (6) ◽

pp. 1517-1536 ◽

Cited By ~ 67

Author(s):

Thierry Goudon ◽

Pierre-Emmanue Jabin ◽

Alexis Vasseur

Keyword(s):

Hydrodynamic Limit ◽

Fine Particles ◽

Stokes Equations ◽

Navier Stokes ◽

Navier Stokes Equations

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Simulation of In-Flight Reduction of the Fine Iron Ore Concentrate by Hydrogen

Chemical Product and Process Modeling ◽

10.1515/cppm-2016-0021 ◽

2017 ◽

Vol 12 (1) ◽

Cited By ~ 3

Author(s):

Bahador Abolpour ◽

M. Mehdi Afsahi ◽

Ataallah Soltani Goharrizi ◽

Mehdi Azizkarimi

Keyword(s):

Residence Time ◽

Fine Particles ◽

Stokes Equations ◽

Direct Reduction ◽

Gaseous Mixture ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Iron Concentrate ◽

Direct Reduction Of Iron ◽

Particle Feed Rate

Abstract A mathematical model has been proposed to simulate a novel method for direct reduction of iron concentrate by hydrogen. Flight of fine particles in a vertical reactor containing a gaseous mixture of H2-N2-H2O has been studied. Effect of generating gaseous jet on the residence time of the particles has been also investigated. Coupled turbulent Navier-Stokes equations with eddy kinetic energy equation have been solved using a developed homemade code. Kinetics of this reaction has been studied using the unreacted core model. Accuracy of the model predictions has been approved by the experimental data. Finally, effects of vital variables (i. e. temperature, particle size, hydrogen concentration and particle feed rate) on the particle residence time and also fractional conversion have been studied.

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Remarks on the asymptotic behaviour of solutions to the compressible Navier–Stokes equations in the half-line

Proceedings of the Royal Society of Edinburgh Section A Mathematics ◽

10.1017/s030821050200032x ◽

2002 ◽

Vol 132 (03) ◽

pp. 627

Keyword(s):

Asymptotic Behaviour ◽

Stokes Equations ◽

Half Line ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Asymptotic Behaviour Of Solutions

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Effects of stator splitter blades on aerodynamic performance of a single-stage transonic axial compressor

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.14.4.2020.05.0579 ◽

2020 ◽

Vol 14 (4) ◽

pp. 7369-7378

Author(s):

Ky-Quang Pham ◽

Xuan-Truong Le ◽

Cong-Truong Dinh

Keyword(s):

Stokes Equations ◽

Three Dimensional ◽

Axial Compressor ◽

Aerodynamic Performance ◽

Numerical Results ◽

Single Stage ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Operating Stability ◽

Length Coverage

Splitter blades located between stator blades in a single-stage axial compressor were proposed and investigated in this work to find their effects on aerodynamic performance and operating stability. Aerodynamic performance of the compressor was evaluated using three-dimensional Reynolds-averaged Navier-Stokes equations using the k-e turbulence model with a scalable wall function. The numerical results for the typical performance parameters without stator splitter blades were validated in comparison with experimental data. The numerical results of a parametric study using four geometric parameters (chord length, coverage angle, height and position) of the stator splitter blades showed that the operational stability of the single-stage axial compressor enhances remarkably using the stator splitter blades. The splitters were effective in suppressing flow separation in the stator domain of the compressor at near-stall condition which affects considerably the aerodynamic performance of the compressor.

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