Effects of Turbulent Models and Baffle Position on the Hydrodynamics of Settling Tanks

In this paper, the numerical results of hydrodynamic modeling of primary settling tanks are presented. The flow field is assumed to be incompressible and non-buoyant. The effects of two different types of turbulence model, standard k-\varepsilon and RNG, are compared with each other. The effects of an inlet baffle on the hydrodynamics of settling tanks are also studied. Results are obtained for the primary settling tank of the city of Sarnia, Ontario, Canada. The effects of the existence and position of another interior baffle in the settling tanks are also studied. Results in the different parts are compared with experimental and numerical data and showed good agreement. Comparison between two models of turbulence shows that the numerical results of the flow field, especially the streamline curvature, are not the same, in spite of having nearly equal results in the streamwise velocity component.