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Chemical Papers

, Volume 73, Issue 2, pp 469–480 | Cite as

Influence of the vessel shape on the performance of a mechanically agitated system

  • Mohammed FoukrachEmail author
  • Mohamed Bouzit
  • Houari Ameur
  • Youcef Kamla
Original Paper
  • 20 Downloads

Abstract

The shape of the tank plays an important role in the hydrodynamic performance of the agitation. A 3D simulation was done using CFD calculation code (CFX16.0). The study was carried out for large Reynolds number: 104–2.105. Navier–Stokes equations governing the phenomenon are solved by a method of discretization finite volume. The turbulence model used is the k–ε standard type. Our main goal was to study the influence of the shape of the tank mechanically agitated by Rushton turbine. Four configurations were used: cylindrical tank, polygon tank without/with baffles (vertical baffle and circular) and circular baffle cut four sides with the same angle. The effect of the shape of the tank and the baffle shape has been studied. Comparing our results seems favorable and gives very good agreement with the experimental results of the literature (Karcz and Major in Chem Eng Process 37:249–256.  https://doi.org/10.1016/S0255-2701(98)00033-6, 1998).

Keywords

Rushton turbine Agitation Baffles Stirred vessel Newtonian fluid ANSYS CFX code 

List of symbols

a

Blade length (m)

b

Blade height (m)

B

Width of baffles (M)

c

Impeller off-bottomed clearance (m)

C

Torque (N m)

d

Disc diameter (m)

D

Impeller diameter (m)

dS

Shaft diameter (m)

e

Disc thickness (m)

H

Vessel tank height (m)

N

Impeller rotational speed (1/s)

NP

Power number (dimensionless)

P

Power (W)

R

Radial coordinate (m)

Re

Reynolds number (dimensionless)

T

Tank diameter (m)

V

Velocity (m/s)

Vz

Axial velocity (m/s)

Vθ

Tangential velocity (m/s)

Vr

Radial velocity (m/s)

w

Baffle length (m)

Greek letters

τ

Shear stress (Pa)

ρ

Fluid density (kg/m3)

η

Viscosity (Pa s)

θ

Angular coordinate (degree)

ω

Angular velocity (rad/s)

α

Cut angle (degree)

Subscripts

CFD

Computational fluid dynamic

PBT

Pitched blade turbine

PIV

Particle image velocity

RRF

Rotating reference frame

MRF

Multiple reference frame

LDA

Laser eddy anemometry

LES

Large eddy simulation

VB

Vertical baffles

CHB

Circular horizontal baffle

CHCB

Circular horizontal cut baffle

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Copyright information

© Institute of Chemistry, Slovak Academy of Sciences 2018

Authors and Affiliations

  • Mohammed Foukrach
    • 1
    Email author
  • Mohamed Bouzit
    • 1
  • Houari Ameur
    • 2
  • Youcef Kamla
    • 3
  1. 1.Faculty of Mechanical EngineeringUniversity of Sciences and Technology, USTO-MBOranAlgeria
  2. 2.Institute of Science and TechnologyUniversity Center of Naama (Ctr Univ Naama)NaamaAlgeria
  3. 3.Faculty of TechnologyUniversity Hassiba Ben BoualiOuled FaresAlgeria

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