Characterization on the hydrodynamics of a covering-plate Rushton impeller

doi:10.1016/j.cjche.2017.11.015

Chinese Journal of Chemical Engineering ›› 2018, Vol. 26 ›› Issue (6): 1392-1400.DOI: 10.1016/j.cjche.2017.11.015

• General reactor • 上一篇下一篇

Characterization on the hydrodynamics of a covering-plate Rushton impeller

Tenglong Su¹, Fengling Yang^1,2, Meiting Li¹, Kanghui Wu¹

1 School of Mechanical Engineering, Shandong University, Jinan 250061, China;
2 Key Laboratory of High Efficiency and Clean Mechanical Manufacture(Shandong University), Ministry of Education, Shandong University, Jinan 250061, China

收稿日期:2017-07-24 修回日期:2017-10-14 出版日期:2018-06-28 发布日期:2018-08-03
通讯作者: Fengling Yang,E-mail address:fly@sdu.edu.cn
基金资助:
Supported by the Key Development Foundation of Shandong province (2016GGX103035).

Characterization on the hydrodynamics of a covering-plate Rushton impeller

Tenglong Su¹, Fengling Yang^1,2, Meiting Li¹, Kanghui Wu¹

1 School of Mechanical Engineering, Shandong University, Jinan 250061, China;
2 Key Laboratory of High Efficiency and Clean Mechanical Manufacture(Shandong University), Ministry of Education, Shandong University, Jinan 250061, China

Received:2017-07-24 Revised:2017-10-14 Online:2018-06-28 Published:2018-08-03
Contact: Fengling Yang,E-mail address:fly@sdu.edu.cn
Supported by:
Supported by the Key Development Foundation of Shandong province (2016GGX103035).

摘要/Abstract

摘要： A modified Rushton impeller with two circular covering-plates mounted on the upper and lower sides of the blades was designed. There are gaps between the plates and the blades. The turbulent hydrodynamics was analyzed by the computational fluid dynamics (CFD) method. Firstly, the reliability of the numerical model and simulation method was verified by comparing with the experimental results from literature. Subsequently, the power consumption, flow pattern, mean velocity and mixing time of the covering-plate Rushton impeller (RT-C) were studied and compared with the standard Rushton impeller (RT) operated under the same conditions. Results show that the power consumption can be decreased about 18%. Compared with the almost unchanged flow field in the lower stirred tank, the mean velocity was increased at the upper half of the stirred tank. And in the impeller region, the mean axial and radial velocities were increased, the mean tangential velocity was decreased. In addition, the average mixing time of RT-C was shortened about 4.14% than the counterpart of RT. The conclusions obtained here indicated that RT-C has a more effective mixing performance and it can be used as an alternative of RT in the process industries.

关键词: Covering-plate Rushton impeller (RT-C), Power consumption, Flow pattern, Mean velocity, Mixing time, Computational fluid dynamics (CFD)

Abstract: A modified Rushton impeller with two circular covering-plates mounted on the upper and lower sides of the blades was designed. There are gaps between the plates and the blades. The turbulent hydrodynamics was analyzed by the computational fluid dynamics (CFD) method. Firstly, the reliability of the numerical model and simulation method was verified by comparing with the experimental results from literature. Subsequently, the power consumption, flow pattern, mean velocity and mixing time of the covering-plate Rushton impeller (RT-C) were studied and compared with the standard Rushton impeller (RT) operated under the same conditions. Results show that the power consumption can be decreased about 18%. Compared with the almost unchanged flow field in the lower stirred tank, the mean velocity was increased at the upper half of the stirred tank. And in the impeller region, the mean axial and radial velocities were increased, the mean tangential velocity was decreased. In addition, the average mixing time of RT-C was shortened about 4.14% than the counterpart of RT. The conclusions obtained here indicated that RT-C has a more effective mixing performance and it can be used as an alternative of RT in the process industries.

Key words: Covering-plate Rushton impeller (RT-C), Power consumption, Flow pattern, Mean velocity, Mixing time, Computational fluid dynamics (CFD)

Tenglong Su, Fengling Yang, Meiting Li, Kanghui Wu. Characterization on the hydrodynamics of a covering-plate Rushton impeller[J]. Chinese Journal of Chemical Engineering, 2018, 26(6): 1392-1400.

Tenglong Su, Fengling Yang, Meiting Li, Kanghui Wu. Characterization on the hydrodynamics of a covering-plate Rushton impeller[J]. Chin.J.Chem.Eng., 2018, 26(6): 1392-1400.

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Characterization on the hydrodynamics of a covering-plate Rushton impeller

Characterization on the hydrodynamics of a covering-plate Rushton impeller

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