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).
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Abbreviations
- 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)
- d S :
-
Shaft diameter (m)
- e :
-
Disc thickness (m)
- H :
-
Vessel tank height (m)
- N :
-
Impeller rotational speed (1/s)
- N P :
-
Power number (dimensionless)
- P :
-
Power (W)
- R :
-
Radial coordinate (m)
- Re :
-
Reynolds number (dimensionless)
- T :
-
Tank diameter (m)
- V :
-
Velocity (m/s)
- V z :
-
Axial velocity (m/s)
- V θ :
-
Tangential velocity (m/s)
- V r :
-
Radial velocity (m/s)
- w :
-
Baffle length (m)
- 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)
- 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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Foukrach, M., Bouzit, M., Ameur, H. et al. Influence of the vessel shape on the performance of a mechanically agitated system. Chem. Pap. 73, 469–480 (2019). https://doi.org/10.1007/s11696-018-0606-4
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DOI: https://doi.org/10.1007/s11696-018-0606-4