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Published on: August 26, 2019
Flow field prediction in full-scale Carrousel oxidation ditch by using computational fluid dynamics
Yin Yang1, Yingying Wu, Xiao Yang
1School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan, Hubei 430074, People's Republic of China.
Summary
A new computational fluid dynamics (CFD) model, the moving wall model, accurately simulates flow in Carrousel oxidation ditches with multiple disc aerators, reducing computational load and improving design.
Area of Science:
- Environmental Engineering
- Fluid Dynamics
- Wastewater Treatment
Background:
- Optimizing flow fields in large-scale Carrousel oxidation ditches is crucial for efficient wastewater treatment.
- Simulating the complex fluid motion generated by numerous disc aerators presents a significant computational challenge.
Purpose of the Study:
- To develop and validate a computational fluid dynamics (CFD) tool for simulating flow fields in full-scale Carrousel oxidation ditches.
- To introduce a novel 'moving wall model' for efficient simulation of multiple disc aerators.
Main Methods:
- Utilized computational fluid dynamics (CFD) to model a full-scale Carrousel oxidation ditch at Ping Dingshan Sewage Treatment Plant.
- Developed a 'moving wall model' to represent the fluid motion induced by multiple disc aerators.
- Validated simulation results against experimental data.
Main Results:
- The moving wall model effectively simulated the flow field in the oxidation ditch with simultaneous operation of multiple disc aerators.
- The proposed CFD method significantly reduced the number of grid cells and computational requirements.
- CFD modeling accurately characterized the overall flow patterns within the full-scale tank.
Conclusions:
- The moving wall model offers a computationally efficient and accurate approach for simulating flow in Carrousel oxidation ditches.
- CFD modeling serves as a valuable tool for enhancing the hydrodynamic design and performance of oxidation ditches.
- This approach can aid in optimizing wastewater treatment processes through improved bioreactor design.
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