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Oxygen transfer and energy dissipation rate in surface aerator
Bimlesh Kumar1, Achanta Ramakrishna Rao
1Department of Civil Engineering, Indian Institute of Science, Bangalore 560 012, India. bimlesh.iisc@gmail.com
Bioresource Technology
|February 17, 2009
Summary
This study correlates oxygen transfer rate with energy dissipation rate (epsilon) in surface aerators. A scale-up equation was developed for optimizing mixing and oxygen transfer in similar systems.
Area of Science:
- Chemical Engineering
- Fluid Dynamics
- Environmental Engineering
Background:
- Turbulent kinetic energy dissipation rate (epsilon) is crucial for mixing efficiency in surface aerators.
- Accurate determination of epsilon within the impeller stream is vital for achieving desired mixing levels.
Purpose of the Study:
- To calculate the energy dissipation rate in geometrically similar unbaffled surface aeration systems.
- To develop a scale-up equation for the oxygen transfer process based on energy dissipation.
Main Methods:
- Utilized commercial software VisiMix for computational fluid dynamics (CFD) simulations.
- Analyzed geometrically similar unbaffled surface aeration systems.
Main Results:
- Established a unique correlation between oxygen transfer rate and energy dissipation rate in similar systems.
- Developed a simulation-based scale-up equation for oxygen transfer.
Conclusions:
- The energy dissipation rate (epsilon) is a key parameter for scaling up oxygen transfer in surface aerators.
- The developed scale-up equation provides a method for optimizing mixing and oxygen transfer processes.
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