A Perforated Baffle Design to Improve Mixing in Contact Tanks
| Autor: | Ender Demirel, M. Anil Kizilaslan, Mustafa M. Aral, Nazhmiddin Nasyrlayev, A. Tolga Kurumus |
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| Rok vydání: | 2020 |
| Předmět: |
lcsh:TD201-500
lcsh:Hydraulic engineering Materials science Computer simulation Turbulence Geography Planning and Development Flow (psychology) Perforation (oil well) Mixing (process engineering) perforated baffle Baffle water treatment Dead zone Mechanics Aquatic Science computational fluid dynamics (CFD) Biochemistry hydraulic and mixing efficiencies lcsh:Water supply for domestic and industrial purposes lcsh:TC1-978 contact tank Solidity Water Science and Technology |
| Zdroj: | Water Volume 12 Issue 4 Water, Vol 12, Iss 1022, p 1022 (2020) |
| ISSN: | 2073-4441 |
| DOI: | 10.3390/w12041022 |
| Popis: | In this study, a perforated baffle design is proposed to improve mixing in contact tanks. Turbulent flow through the perforated baffle is studied at the perforation hole scale. The contribution of jets emerging from the perforations to the mixing process is evaluated in terms of standard mixing indexes for various perforation parameters, such as the solidity ratio and hole diameter. Based on numerical simulation results, the two sets of perforated baffles that yielded the highest performance were manufactured from polycarbonate and tracer studies were conducted on a laboratory model. Comparison of numerical and experimental results demonstrates that the numerical model developed is reliable in simulating the flow through the perforated baffles and the associated mixing level in the contact tank. Numerical simulations indicate that the jet flow structure through the perforated baffle penetrates to the recirculation zones in the neighboring chambers and turns the dead zones into active mixing zones. Furthermore, large scale turbulent eddies shed by the perforations contribute to the mixing process in the chambers of the tank. With the use of the perforated baffle design, it is shown that the hydraulic efficiency of the tank can be improved from average to superior according to the baffling factor, and the associated mixing in the proposed design can be improved by 31% according to the Morrill index. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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