Influence of blade shape on performance in inverse umbrella aerator
MING Jiayi1*, DONG Liang1,2, LIU Houlin1, ZHAO Yuqi1, YAO Han3
1. National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.Sichuan Provincial Key Lab of Process Equipment and Control, Zigong, Sichuan 643000, China; 3. Shenyang Blower Group, Petrochemical Pump Co. Ltd., Shen-yang, Liaoning 110869, China
Abstract:In order to study the effect of radial straight blade and leaned blade on the performance of inverse umbrella aerator and obtain the flow characteristic of a oxidation ditch driven by two inverse umbrella aerators with different kinds of blade shape, a lab scale oxidation ditch according with geometric similarity, kinematic similarity and dynamic similarity was taken as the research object. The volume of fluid(VOF)model was adopted and the standard k-ε turbulence model was applied to close the governing equations. Through changing the blade shape of inverse umbrella aerator, three-dimensional numerical simulations were conducted. The results show that the power assumption of these two kinds of inverse umbrella aerators is much the same, the blade shape has a significant impact on oxygenation capacity and plug-flow capacity on the inverse umbrella aerator: under the drive of inverse umbrella aerator with radial straight blade, the gas volume fraction of the section crossing the driving shaft in the oxidation ditch is 0.66% higher than that in the oxidation ditch driven by the inverse umbrella aerator with leaned blade; while the inverse umbrella aerator with radial straight blade has a stronger ability to promote the fluid near the surface, the inverse umbrella aerator with leaned blade does better on driving fluid at the bottom of the ditch, with the dead water zone 0.70% less than that in the ditch driven by the inverse umbrella aerator with radial straight blade. The fluid stirred by the inverse umbrella aerator with leaned blade flows to the wall at a higher speed. The flow distribution of the oxidation ditch driven by two inverse umbrella aerators is symmetrical. The downstream inverse umbrella aerator has an ability to lift and accelerate the incoming flow.
明加意*, 董亮,, 刘厚林, 赵宇琪, 姚瀚. 叶片形状对倒伞曝气机性能的影响[J]. 排灌机械工程学报, 2018, 36(2): 104-110.
MING Jiayi*, DONG Liang,, LIU Houlin, ZHAO Yuqi, YAO Han. Influence of blade shape on performance in inverse umbrella aerator. Journal of Drainage and Irrigation Machinery Engin, 2018, 36(2): 104-110.
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