CFD modelling of a secondary settling tanks: generalization based on database relations


  • Ondřej Švanda Czech Technical University in Prague, Faculty of Civil Engineering, Department of Sanitary and Ecological Engineering, Thákurova 2077/7, Prague 6, Czech Republic
  • Jaroslav Pollert Czech Technical University in Prague, Faculty of Civil Engineering, Department of Sanitary and Ecological Engineering, Thákurova 2077/7, Prague 6, Czech Republic



CFD modelling, secondary settling tank, sludge database


The modelling of a secondary settling tank area using numerical methods has been quite extensively explored and researched by numerous authors and papers. These developed models utilize different approaches, from efforts to create a solely deterministic models to attempts to generalize calibrated empirical models. Nevertheless, the processes are not easy to simulate due to the high complexity of the physics involving multiple phases, bio-chemical reactions and non-Newtonian fluids. Therefore, an additional research effort should be focused on improving these models and to validate and verify them against experimental measurements. This article is focused on creating a numerical model for settling tank optimization, which builds on the previous works and is then extended with newly obtained relations from vast experimental measuring using the database approach. The objective is to create a model, which is based on an obtained relation and could easily be adjusted to different flow scenarios and sludge types at different wastewater treatment plants.


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