Flow characteristics of the new type of mixer in wastewater treatment

Flow characteristics of the new type of mixer in wastewater treatment

Fei TianWeidong Cao Xiaoli Dai Mingxiong Ou 

School of energy and power engineering, Jiangsu University, Zhenjiang 212013, China

National Research Center of Pumps and Pumping System Engineering and Technology, Zhenjiang 212013, China

Yatai Pump &Valve Co., Ltd., Taizhou, Jiangsu 220000, China

Corresponding Author Email: 
9 February 2018
18 June 2018
30 September 2018
| Citation



This paper studies the flow field of a new type of submersible mixer with two impellers and six blades in the wastewater treatment pool by using large-scale software, such as Pro/engineering, FLUENT 15.0 and ICEM. After that, it numerically simulates the wastewater treatment pool using the RNG k-ε turbulent model and the mobile coordinate measuring system, and analyzes the macro fluid field and flow field distribution of the sections. The fluid in the wastewater treatment pool can be propelled by the new type of mixer, and the fluid flows along the axial direction of the submersible mixer and diffuses radially. Eight water and sludge cycles are formed in the pool, and the fluid in the pool forms two high-flow region and eight low-flow regions. The velocity distribution in the pool is distributed symmetrically along the plane Z=0m and the plane X=1.75m. As the new type of mixer is installed close to the bottom of the pool, the position with the maximum velocity offsets gradually to the bottom of the pool with the increasing distance to the impeller. The new type of mixer is different from the traditional submersible mixer, in that the fluid mixed by the new one can circulate fully on both sides of the submersible mixer. Consequently, this new type of submersible mixer can mix more fluid, and there will be a smaller dead zone in the whole pool with less sludge at the bottom. This simulation method can guide the application of mixers in the practical wastewater treatment.


new type of mixer, CFD, flow filed, simulation, fluid dynamics

1. Introduction
2. Study Object
3. Simulation
4. Simulation Analysis
5. Results

This work was supported by Natural Science Foundation of Jiangsu Province (Grant Nos.: BK20160521, NO.: BK20170554), Jiangsu Postdoctoral Funding Program (2018K017A) Key Development Project of Zhenjiang City (Grant Nos.: SH2017049), the National Natural Science Foundation of China (Grant Nos.: 31601676)


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