Numerical Study of Vortex Formation inside a Stirred Tank

The computational fluid dynamics (CFD) study of
stirred tank with the air-water interface are carried out in the presence
of different types of the impeller and with or without baffles. A
multiple reference frame (MRF) approach with the volume of fluid
(VOF) method is used to capture the air-water interface. The RANS
(Reynolds Averaged Navier-Stokes) equations with k-ε turbulence
model are solved to predict the flow behavior of water and air phase
which are treated as a different phases. The predicted results have
shown that the VOF method is able to capture the interface in the
unbaffled tank. While, the VOF method is showing an unfeasible
results in the baffled tank with high rotational impeller speed. For
continuous stirred tank, the air-water interface is disturbed by the
inflow and the level of water is also increased with time.

• Divya Rajavathsavai
• Akhilesh Khapre
• Basudeb Munshi

• Computational Fluid Dynamics
• stirred tank
• airwater interface
• multiple reference frame
• volume of fluid
• Reynolds Averaged Navier-Stokes equations.

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