Numerical Model for Laminar Flow in Agitated Vessel by tow Blades Impeller


  • L Rahmani
  • O Seghier
  • A Benmoussa
  • B Draoui
  • E Benachour



A large number of chemicals, biochemical or petrochemical industry operations are performed in stirred tanks or in mechanically agitated vessels. The optimum operating mode of these equipments requires a detailed knowledge of the hydrodynamic behavior induced by the agitator. In this piece of work the characterization of the laminar viscous fluid flow fields in a cylindrical stirred tank is agitated by inclined blades anchor agitator studied. The computational fluid dynamic (CFD) model based on an implicit fractional step scheme and control volume method was developed for the spatial discretization of the Navier-Stokes, formulated in Cartesian coordinates primitives variables (u, v, p, T) on unstructured triangular mesh. Some simulations of the flow around an anchor with straights blades allowed validating the used method. We have analyzed the influence of the tilt blades degree on the hydrodynamic flow behaviors, such as the stream function, the velocity field, the velocities components, and the power consumption. The comparison between some of the obtained results with literature data, have showed a satisfactory agreement.


MEBARKI Brahim, DRAOUI Belkacem, RAHMANI Lakhdar, BOUANINI Mohamed and BENACHOUR El-Hadj, Etude numérique de l’agitation d’un fluide viscoplastique au sein d’une cuve agitée par un mobile de type bipale, Journal of Scientific Research, Vol.0 .n.1, (2010).

M. Marouche, Hydrodynamique d’un système d’agitation en fluide viscoplastique et en régime laminaire inertiel, Thèse de Doctorat de l’INP Toulouse, France, (2002).

Atkinson B., Smith J.M., Characteristics of heat transfer to non-Newtonian liquids (part 2), Brit. Chem. Eng. 11 (2) 124-127, (1966).

Nagata S., Mixing: Principles and Applications, Halstead Press, New York, (1975).

Uhl V.W., Voznick H.P., The anchor agitator, Chem. Eng. Progr. 56 (3) 72-77. (1960).

Abid M.S., Xuereb C. and Bertrand J, Hydrodynamics in vessels stirred with anchors and gate agitators: Necessity of a 3-D modelling, T. Instn. Chem. Eng. A 70 377-384, (1992).

Hirata, Y., Aoshima, Y, Formation and growth of cavern in yield stress fluids agitated under baffled and non-baffled conditions. Chem. Eng. Res. Des 74 n.4, 438-444, (1996).

Ein-Mozaffari, F., Bennington, C. P. J., Dumont, G. A, Suspension yield stress and the dynamic response of agitated pulp chests. Chem. Eng. Sc. 60, 2399-2408, (2005).

Bertrand, F., Tanguy, P. A., Brito De La Fuente, E, A new perspective for the mixing of yield stress fluids with anchor impellers, J. Chem. Eng. Jap. 29 n.1, 51-58, (1996).

Curran, S. J., Hayes, R. E., Afacan, A., Williams, M., Tanguy, P. 2000 Experimental mixing of a yield stress fluid in a laminar stirred tank. Ind. Eng. Chem. Res. 39, 195-202.

Anne-Archard, D, Marouche, M., Boisson, H. C. Hydrodynamics and Metzner-Otto correlation in stirred vessels for yield stress fluids, Chem. Eng. J. 125 n.1, 15-24, (2006).

T.C. Papanastasiou, Flows of materials with yield, J. Rheol. 31 385, (1987).

E.J. O’Donovan, R.I. Tanner, Numerical study of the Bingham squeeze film problem, J. Non-Newton. Fluid Mech. 15 75, (1984).

M. Bercovier, M. Engelman, A finite element method for incompressible non-Newtonian flows, J. Comput. Phys. 36 313, (1980).

Beverly. C and Tanner. R, Numerical analysis of extrudate swell in viscoelastic materials with yield stress, J. Rheol., vol. 33, pp. 989-1009, (1989).

L. Rahmani, B. Draoui, B. Mebarki, M. Bouanini and O. Hami, Heat transfer to Bingham fluid during laminar flow in agitated tank. International Review of Mechanical Engineering, Vol. 3, N.2, (2009).

L. Rahmani, B. Draoui, B. Mebarki, M. Bouanini, E. Benachour, and B. Allaoua, Comparison of power consumption for viscoplastic fluid in a rotating vessel with anchor, gate and two blades impellers, International Review of Mechanical Engineering. Vol. 3, N.4, (2009).

Pedrosa S M C P, Nunhez J R, The behaviour of stirred vessels with anchor type impellers, Computers and Chemical Engineering 24, pp 1745-1751, (2000).

Rahmani, B.Mebarki, B. Draoui, M. Bouanini, O. Hami, et E.Benachour, Etude hydrodynamique de l’agitation de fluides newtoniens dans une cuve cylindrique munie par une barrière, Séminaire international sur la physique énergétique (SIPE09). Bechar, Algerie, (2008).

O. Hami, B. Draoui, B. Mebarki, L. Rahmani and M. Bouanini, Numerical model for laminar flow and heat transfer in an agitated vessel by inclined blades anchor, ICHMT International Symposium on Advances in Computational Heat Transfer. May 11-16, Marrakech, Morocco, (2008).



How to Cite

Rahmani, L., Seghier, O., Benmoussa, A., Draoui, B. and Benachour, E. (2016) “Numerical Model for Laminar Flow in Agitated Vessel by tow Blades Impeller”, The International Journal of Multiphysics, 10(4), pp. 427-440. doi: 10.21152/1750-9548.10.4.427.