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Computational fluid dynamics simulation in cone-bottom stirred tanks with a Rushton and pitchedblade turbines

10.24050/reia.v20i40.1676
Published 2023-12-19
Articles

Abstract

Computational Fluid Dynamics (CFD) is a tool frequently used for the optimization
and improvement of industrial processes. In this work, the CFD simulation is used for
analyzing the appropriate power in stirred-tank systems with three different types of cones
at the bottom of the tank and with two types of impellers: 45° pitch 4- bladed turbine (axial
impeller) and Rushton standard turbine (radial impeller). The simulation was carried out in
a stirred tank with a diameter of 27 cm and with different cone diameters and height ratios
are analyzed. Also, 4 rotation speeds (50, 100, 300, and 600 rpm) were evaluated to describe
the transition to turbulent states. Reynolds Stress Model (RSM) and the Moving Reference
Frame are used. The results show that the power decrease with the axial impeller when
this is operated at low Reynolds number values meanwhile the radial impeller presented an
increase in the values of power when the cone is introduced inside the tank. By increasing
the Reynolds number an exponential increase in the power volume of each impeller is
made. Also, the inclusion of a 4-impeller blade inclination between laminar and transition
shows a significant saving in power consumption and for turbulent regimes, the inclusion
of geometries in the bottom of the tank affects power consumption. Finally, the results are
validated using experimental data and show that the absolute deviations are below 4 %.

Keywords

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Authors

  • Luis Fernando Cardona Palacio

    Universidad Católica Luis Amigó - Colombia

    https://orcid.org/0000-0002-6526-9508

  • Juan E. Arismendy

    Universidad Pontificia Bolivariana - Colombia

  • German Camilo Quintana Marín

    Universidad Pontificia Bolivariana - Colombia

  • Hader Humberto Alzate Gil

    Universidad Pontificia Bolivariana - Colombia

  • Diego A. Hincapié

    Instituto Tecnológico Metropolitano - Colombia

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