Effects of propeller layout position on flow characteristics in oxidation ditch
CHEN Bin1, WANG Bingqi1, ZHANG Hua1, WANG Qiang1, WANG Zhen2
1.Research Institute of Chemical Machinery, HeFei University of Technology, Hefei, Anhui 230009, China; 2.NanJing LanShen Pump Co.Ltd., Nanjing, Jiangsu 211500, China
Abstract：To avoid sludge deposition in a running track type oxidation ditch, the layout position of four propellers is altered when the pool structure remains unchanged. The steady fluid flow field in the whole ditch is simulated by means of STARCCM+ software plus the standard k-ε turbulence model when these propellers are in operation. The velocity distribution in each section in the ditch and the velocity distribution in the whole flow field as well as the dead water zone are analysed to specify the optimal propeller layout position for the pool. Results show that the propellers′ position has a great influence on velocity distribution, and a too large or too small distance between a propeller and the middle baffle wall can lead to an uneven velocity distribution and an enlarged dead water zone. Especially, when the distance is about 0.85 times the sum of the circular baffle wall radius and the distance of the circular baffle wall centre to the middle baffle wall, the average fluid velocity is as high as 0.35 m/s in the major sections observed with the smallest dead water zone. Flow separation zones are inevitable at the back of the circular baffle wall and the two ends of middle baffle wall, but they can be diminished by changing propellers′ position. In addition, there is an obvious vortex phenomenon in the corners of the ditch by virtue of the interaction between the propellers and the pitch walls.
陈斌, 王炳祺, 张华, 王强, 王震. 推流器布置对氧化沟流场特性的影响[J]. 排灌机械工程学报, 2016, 34(3): 227-231.
CHEN Bin, WANG Bingqi, ZHANG Hua, WANG Qiang, WANG Zhen. Effects of propeller layout position on flow characteristics in oxidation ditch. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(3): 227-231.
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