CFD Modelling of Circular Baffled Aeration Tanks

The hydraulic design of energy intensive aeration systems is quite essential in the context of rapid urbanization and population explosion. Nowadays, validated computational fluid dynamics (CFD) models are used for analysing the flow fields in aeration tanks owing to several difficulties associated with experimental investigations. The main objective of the present study is to analyse the effect of grid resolution, k-epsilon turbulence models, and pressure velocity coupling schemes on turbulent flow fields in a baffled aeration tank stirred by six bladed Rushton turbine. The grid resolution and k-epsilon turbulence models found to have significant impact on flow fields while various pressure-velocity coupling schemes improved the numerical convergence without improving the accuracy of the solutions further. Thus fine grids associated with realizable k-epsilon turbulence model is effective in steady state CFD modelling of baffled aeration tanks.