Flow field simulation and analysis of rotating magnetic photocatalytic wastewater treatment reactor
Wu Chundu1, Zheng Kun1, Xie Qingjie1, Zhu Mingkai1, Bai Ge2
1.School of The Environment and Safety Engineering, Jiangsu Uiversity, Zhenjiang, Jiangsu 212013, China; 2 China Petroleum Pipeline Engineering Corporation, Langfang, Hebei 065000, China
Abstract:Environmental equipments should be designed for different wastewater working conditions. However, the internal flow field in a wastewater treatment reactor is extremely complex, thus it is difficult to determine the reactor working conditions and purifying effects based on designer′s experience alone. In order to study the spatial distribution characteristics of flow field in rotating magnetic photocatalytic wastewater treatment reactors, a physical model of such a reactor is built using Gambit, and a series of numerical simulations of 3-D the flow field in it are conducted by means of Fluent, the influences of rotating speed on the liquid flow field characteristics are analyzed at three kinds of speed. The results show that the fluid flow velocity increases with the speed. The fluid flow is weaker at the speed of 0.2 rad/s; even the fluid starts to circulate adequately at the speed of 0.5 rads/s, the flow velocity is still relatively low. At 1.0 rad/s rotating speed, the fluid has a higher turbulent kinetic energy and a uniform flow distribution, but there are vortices in the flow field. An analysis of the flow field characteristics at different rotating speeds cam provide a reference for optimization design of the reactor structure.
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