Effect of the Tank Design on the Flow Pattern Generated with a Pitched Blade Turbine

The effect of the tank design on the hydrodynamic structure is carried out in three tanks; cylindrical tank, curved tank and spherical tank; equipped with a six-pitched blade turbine (PBT6). The hydrodynamic behaviour is numeri- cally predicted by the resolution of the Navier-Stokes equations in conjunction with the Renormalization Group (RNG) of the k-e turbulence model. These equations are solved by a control volume discretization method. The numerical results from the application of the CFD code "Fluent" with the Multi Reference Frame (MRF) model are presented in the impeller stream region. Particularly, the velocity components and the turbulent characteristics are presented in different planes con- taining the blade. The power consumption of these stirred tanks was calculated to choose the most effective system. The comparison between the numerical results and the experimental data showed a good agreement.

[1]  W. Kelly,et al.  Using CFD to predict the behavior of power law fluids near axial-flow impellers operating in the transitional flow regime , 2003 .

[2]  Zied Driss,et al.  Effect of the turbulence models on Rushton turbine generated flow in a stirred vessel , 2011 .

[3]  Michael Yianneskis,et al.  Experiments and predictions of the transition of the flow pattern with impeller clearance in stirred tanks , 2001 .

[4]  M. Abid,et al.  Effects of baffle length on turbulent flows generated in stirred vessels , 2011 .

[5]  Constantin Dan Tacǎ,et al.  Power input in closed stirred vessels , 2001 .

[6]  H. Osaka,et al.  Effect of the attack angle on the roll and trailing vortex structures in an agitated vessel with a paddle impeller , 2006 .

[7]  Zied Driss,et al.  Numerical investigation of turbulent flow generated in baffled stirred vessels equipped with three different turbines in one and two-stage system , 2011 .

[8]  Piero M. Armenante,et al.  Velocity profiles in a baffled vessel with single or double pitched-blade turbines , 1996 .

[9]  Jyeshtharaj B. Joshi,et al.  Assessment of standard k–ε, RSM and LES turbulence models in a baffled stirred vessel agitated by various impeller designs , 2008 .

[10]  S. Nagata.  Mixing: Principles and Applications , 1975 .

[11]  J. Aubin,et al.  Modeling turbulent flow in stirred tanks with CFD: the influence of the modeling approach, turbulence model and numerical scheme , 2004 .

[12]  B. Launder,et al.  Progress in the development of a Reynolds-stress turbulence closure , 1975, Journal of Fluid Mechanics.

[13]  Zied Driss,et al.  Computational studies of the pitched blade turbines design effect on the stirred tank flow characteristics , 2010 .

[14]  Angélique Delafosse,et al.  Trailing vortices generated by a Rushton turbine: Assessment of URANS and large Eddy simulations , 2009 .

[15]  A. Gosman,et al.  PREDICTION OF IMPELLER- INDUCED FLOW IN MIXING VESSELS USING MULTIPLE FRAMES OF REFERENCE , 1994 .

[16]  Zdzisław Jaworski,et al.  Modelling of the Turbulent Wall Jet Generated by a Pitched Blade Turbine Impeller: The Effect of Turbulence Model , 2002 .

[17]  D. Deglon,et al.  CFD modelling of stirred tanks: Numerical considerations , 2006 .