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Investigations of Mixing Time Scales in a Baffled Circular Tank with a Surface Aerator
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  • Journal title : Environmental Engineering Research
  • Volume 16, Issue 1,  2011, pp.47-51
  • Publisher : Korean Society of Environmental Engineering
  • DOI : 10.4491/eer.2011.16.1.047
 Title & Authors
Investigations of Mixing Time Scales in a Baffled Circular Tank with a Surface Aerator
Kumar, Bimlesh; Patel, Ajey; Rao, Achanta;
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 Abstract
The oxygen transfer rate is a parameter that characterizes the gas-liquid mass transfer in surface aerators. Gas-liquid transfer mechanisms in surface aeration tanks depend on two different extreme lengths of time; namely, macromixing and micromixing. Small scale mixing close to the molecular level is referred to as micromixing; whereas, macromixing refers to mixing on a large scale. Using experimental data and numerical simulations, macro- and micro-scale parameters describing the two extreme time scales were investigated. A scale up equation to simulate the oxygen transfer rate with micromixing times was developed in geometrically similar baffled surface aerators.
 Keywords
Energy dissipation;Macromixing;Micromixing;Oxygen transfer rate;Surface aerators;Theoretical power per unit volume;
 Language
English
 Cited by
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