Turbulence in flocculators: Effects of tank size and impeller type
Turbulence in flocculators: Effects of tank size and impeller type
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DOI：
10.1002/aic.690430206
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发表时间：
1997-02
期刊：
影响因子：
3.7
通讯作者：
J. Ducoste;M. Clark;R. Weetman
中科院分区：
文献类型：
--
作者：
J. Ducoste;M. Clark;R. Weetman
过去的研究表明，在单位体积的功率相同的情况下，絮凝性能随槽的尺寸和叶轮的类型而变化。进行这项研究，以表征规模和叶轮设计对絮凝过程中产生的湍流的影响。该研究在体积为5-、28-和560-L的三个方形罐中使用Rushton涡轮机和A310翼型叶轮进行。流体速度测量使用双通道激光多普勒测速仪与增强型突发频谱分析仪。絮凝池在0.0016 m2/s3的恒定平均单位质量能量耗散率下操作。结果表明，Rushton涡轮机叶轮的湍流强度和局部湍流能量耗散率均高于A310叶轮。湍流强度被认为是增加与增加坦克的大小，无论叶轮类型。局部湍流能量耗散率下降的Rushton涡轮机和A310叶轮保持不变，增加坦克的大小。
Past research shows that for the same power per unit volume, flocculation performance varies with tank size and impeller type. This study was performed to characterize effects of scale and impeller design on turbulence produced in the flocculation process. The study was performed with a Rushton turbine and an A310 foil impeller in three square tanks of 5-, 28- and 560-L volume. Fluid velocities were measured using a dual-channel laser Doppler velocimeter with an enhanced burst spectrum analyzer. Flocculation tanks were operated at a constant average unit-mass energy-dissipation rate of 0.0016 m2/s3. The results show that the turbulence intensity and local turbulent energy-dissipation rate were higher for the Rushton turbine than for the A310 impeller. The turbulence intensity was found to increase with increasing tank size regardless of impeller type. The local turbulent energy dissipation rate decreased for the Rushton turbine and remained constant for the A310 impeller with increasing tank size.