Journal of Shandong University(Engineering Science) ›› 2019, Vol. 49 ›› Issue (4): 93-98.doi: 10.6040/j.issn.1672-3961.0.2018.530

• Mechanical, Energy and Power Engineering • Previous Articles     Next Articles

Laminar flow field characteristics in the stirred vessel equipped with an eccentric-shaft impeller

Meiting LI1(),Wei LI2,Xiaoguang LI3,Fengling YANG1,*()   

  1. 1. School of Mechanical Engineering, Shandong University, Jinan 250061, Shandong, China
    2. CNPC Eastchina Design Institute Co., Ltd, Qingdao 266071, Shandong, China
    3. Shandong Tianli Drying Technology and Equipment Cop., Ltd., Jinan 250100, Shandong, China
  • Received:2018-12-06 Online:2019-08-20 Published:2019-08-06
  • Contact: Fengling YANG E-mail:172785430@qq.com;fly@sdu.edu.cn
  • Supported by:
    山东省重点研发计划资助项目(2016GGX103035);山东省重点研发计划资助项目(2017GGX70101)

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Abstract:

For the purpose of improving mixing efficiency of the stirred tank with high viscosity fluid laminar flow condition, an eccentric-shaft agitation method was proposed. With a purity of 99% glycerol as medium, and the traditional 2-flat-blade impeller as the research object, the laminar flow fields were numerically studied. The inner diameter of the stirred vessel was 0.3m and the agitated fluid was glycerol. The modeling reliability and simulation methods of the concentric agitation were validated by experimental results. In comparison with the concentric agitation, flow fields generated by eccentric and eccentric-shaft agitation were asymmetrical, and theoverall volume weitghted average velocity of the groove fluid generated by eccentric-shaft agitation could be raised by 68%. And furthermore, when operated under the same speed, the power consumption of eccentric-shaft agitation increased 15.3% than that of concentric agitation. However, the eccentric shaft agitation increased the speed in the tank and expanded the range of disturbance. Accordingly, the superiority of eccentric-shaft agitation of improving the mixing efficiency in the tank was apparent.

Key words: stirred vessel, eccentric-shaft agitation, computational fluid dynamics, laminar flow, power consumption

CLC Number: 

  • TQ051

Fig.1

Configuration of the stirred tanks"

Fig.2

Schematic of the stirred experimental apparatus"

Fig.3

Velocity magnitude at the monitoring point"

Fig.4

Comparisons between simulated axial velocities and experimental data"

Fig.5

Comparison between simulated radial velocities and experimental data"

Fig.6

Velocity vectors and clouds in the axial lengthwise section of the stirred vessel"

Fig.7

Comparison of velocities at different heights"

Table 1

Power number of different methods"

搅拌方式功率准数
中心搅拌4.25
偏心搅拌4.45
偏心轴搅拌4.90
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