Numerical Investigation of Effects of Inlet Placement and Characteristics of Baffles in Settling Tanks

Document Type : Research Paper


1 Assist. Prof., Dept. of Civil Eng., Khajeh Nasireddin Toosi University of Tech., Tehran

2 M.Sc. of Civil Eng., Khajeh Nasireddin Toosi University of Tech., Tehran

3 Ph.D. Student of Civil Eng., Dept. of Civil Eng., Khajeh Nasireddin Toosi University of Tech., Tehran


Settling tanks are one of the main parts of treatment plants and different parameters are effective in the settling tank performance. In this study effects of some of these parameters such as the situation of the inlet opening as well as the existence and position of baffles in the tanks are investigated.  2D numerical simulations of primary settling tanks are carried out using 2D Fluent software and the best position for the  inlet to enhance  the  their performance found  to be in the middle of the tank  with optimum size  of the baffle about 30% the height of settling tank  at a distance about 5-10% settling tank's length.


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