Effects of Blades' Clearance and Helical Angle on the Stirring Torque and Power of the Twin-blade Planetary Mixer

doi:10.3901/JME.2018.20.330

Abstract

Abstract: In the present paper, the 1 L twin-blade planetary mixer is selected as the research object, utilizing the CFD method to systematically research the effecting relation of the blade's geometric parameters (blade-blade clearance, helical angle) of the twin-blade planetary mixer on the mixing torque and the power consumption when mixing the Newtonian fluid(corn syrup). The simulation model of the twin-blade planetary mixer is made comparison validation to experimental data, which in turn make sure the results are reliable. The research results show that decreasing the clearance or increasing the helical angle can increase the mixing torque and power consumption of blades. Increasing the helical angle can increase the kneading time, and decreasing the clearance or increasing the helical angle can enhance the kneading strength of blades. Within certain limits, when the clearance c₁=3.0 mm and the helical angle β_k=35°, the average torque of hollow blade reaches the minimum value 0.046 93 N·m; when the clearance c₁=1.0 mm and the helical angle β_k=55°, the average torque of hollow blade reaches the maximum value 0.068 73 N·m. When the twin-blade planetary mixer stirs the Newtonian fluid, the Power number N_pM and the Reynolds number R_eM show the linear relation, and the effect of clearance on the power characteristic of twin-blade planetary mixer is more notable than the helical angle.

Key words: clearance, helical angle, power, stirring torque, twin-blade planetary mixer

CLC Number:

V512

LIANG Jian, LUO Xiaohui, LI Xiwen, SHI Tielin. Effects of Blades' Clearance and Helical Angle on the Stirring Torque and Power of the Twin-blade Planetary Mixer[J]. Journal of Mechanical Engineering, 2018, 54(20): 330-337.

References

[1] ZAMBAUX J A,HARION J L,RUSSEIL S,et al. Combining two orthogonal secondary flows to enhance the mixing in an annular duct[J]. Chemical Engineering Research & Design,2015,94:702-713.
[2] AMEUR H. Energy efficiency of different impellers in stirred tank reactors[J]. Energy,2015,93:1980-1988.
[3] 李良超,徐斌,杨军. 基于计算流体力学模拟的下沉与上浮颗粒在搅拌槽内的固液悬浮特性[J]. 机械工程学报,2014,50(12):185-191. LI Liangchao,XU Bin,YANG Jun. Sinking/Floating particles solid suspension characteristics in stirred tank based on CFD simulation[J]. Journal of Mechanical Engineering,2014,50(12):185-191.
[4] 魏静,孙旭建,孙伟,等. 双螺杆捏合机转子型线设计与数值模拟[J]. 机械工程学报,2013,19(3):63-73. WEI Jing,SUN Xujian,SUN Wei,et al. Rotor profiles design method and numerical simulation for twin-screw kneader[J]. Journal of Mechanical Engineering,2013,49(3):63-73.
[5] TANGUY P A,BERTRAND F,LABRIE R,et al. Numerical modelling of the mixing of viscoplastic slurries in a twin-blade planetary mixer[J]. Chemical Engineering Research and Design,1996,74(A4):499-504.
[6] 王正方,翟瑞清. 立式捏合机搅拌桨的设计[J]. 固体火箭技术,1993(1):65-69. WANG Zhengfang,ZHAI Ruiqing. The design of stirring blades of vertical kneading machine and parametric calculations[J]. Journal of Solid Rocket Technology,1993(1):65-69.
[7] 王正方,翟瑞清. VKM-5型立式捏合机研制与应用[J]. 固体火箭技术,1992(3):59-64. WANG Zhengfang,ZHAI Ruiqing. The development and application of the VKM-5 type vertical kneading machine[J]. Journal of Solid Rocket Technology,1992(3):59-64.
[8] 杨明金. 立式捏合机混合釜内固体推进剂药浆混合的研究[D]. 武汉:华中科技大学,2008. YANG Mingjin. Research on mixing of solid propellant slurry in tanks of the vertical kneaders[D]. Wuhan:Huazhong University of Science and Technology,2008.
[9] 张嘉琪,李锡文,何锐波,等. 双轴差速立式捏合机混合釜流场特性分析[J]. 华中科技大学学报,2015,43(2):6-10. ZHANG Jiaqi,LI Xiwen,HE Ruibo,et al. Analysis of characteristics of flow field in mixing tank of differential twin shaft vertical kneader[J]. Journal of Huazhong University of Science and Technology,2015,43(2):6-10.
[10] ZHANG J,LI X,HE R,et al. Study on double-shaft mixing paddle undergoing planetary motion in the laminar flow mixing system[J]. Advances in Mechanical Engineering,2015,7(7):1-12.
[11] LIANG J,HE R,ZHAN X,et al. Numerical analysis in the effects of blade's arrangement on the torque load characteristics of the three-blade planetary mixer[C/CD]//Proceedings of the AIP Conference Proceedings,F,2017.
[12] 梁建,李锡文,詹小斌,等. 立式捏合机桨叶结构参数对扭矩和功率特性的影响[J]. 固体火箭技术,2016(6):789-796. LIANG Jian,LI Xiwen,ZHAN Xiaobin,et al. Numerical analysis on effects of geometrical parameters of vertical planetary kneading mixer blades on the characteristics of torque and power[J]. Journal of Solid Rocket Technology,2016(6):789-796.
[13] ZHOU G,TANGUY P A,DUBOIS C. Power Consumption in a double planetary mixer with non-Newtonian and viscoelastic materials[J]. Chemical Engineering Research and Design,2000,78(3):445-453.
[14] SHEKHAR S M,JAYANTI S. Mixing of power-law fluids using anchors:Metzner-Otto concept revisited[J]. Aiche Journal,2003,49(1):30-40.
[15] 易朋兴,胡友民,崔峰,等. 立式捏合机捏合间隙影响CFD分析[J]. 化工学报,2007,58(10):2680-2684. YI Pengxing,HU Youmin,CUI Feng,et al. Numerical investigation of effect of kneading clearance on mixing performance of vertical kneading mixers[J]. Journal of Chemical Industry and Engineering,2007,58(10):2680-2684.
[16] 易朋兴,崔峰,胡友民,等. 立式捏合机搅拌桨螺旋角影响数值分析[J]. 固体火箭技术,2008,31(4):381-385. YI Pengxing,CUI Feng,HU Youmin,et al. Numerical analysis on effects of helix angle of stirring paddle on mixing performance of vertical kneading machine[J]. Journal of Solid Rocket Technology,2008,31(4):381-385.
[17] 梁建,李锡文,史铁林,等. 立式捏合机桨叶结构参数对混合釜流场影响的仿真分析[J]. 固体火箭技术,2017(3):347-352. LIANG Jian,LI Xiwen,SHI Tielin,et al. Numerical analysis of effects of geometrical parameters of blades on flow field in mixing tank of vertical planetary kneading mixers[J]. Journal of Solid Rocket Technology,2017(3):347-352.
[18] 梁建,杨红,魏佳,等. 立式捏合机桨叶扭矩特性的CFD仿真研究[J]. 固体火箭技术,2018(1):78-83. LIANG Jian,YANG Hong,WEI Jia,et al. CFD analysis on the characterisitcs of blades' torque of the twin-blade planetary mixer[J]. Journal of Solid Rocket Technology,2018(1):78-83.
[19] LIANG J,ZHAN X,YANG Y,et al. A numerical investigation of the effects of blade's geometric parameters on the power consumption of the twin-blade planetary mixer[J]. Advances in Mechanical Engineering,2016,8(10):1-12.
[20] DELAPLACE G,GUERIN R,LEULIET J C. Dimensional analysis for planetary mixer:Modified power and Reynolds numbers[J]. Aiche Journal,2005,51(12):3094-3100.
[21] ANDRE C,DEMEYRE J F,GATUMEL C,et al. Dimensional analysis of a planetary mixer for homogenizing of free flowing powders:Mixing time and power consumption[J]. Chemical Engineering Journal,2012,198:371-378.
[22] AUGER F,DELAPLACE G,BOUVIER L,et al. Hydrodynamics of a planetary mixer used for dough process:Influence of impeller speeds ratio on the power dissipated for Newtonian fluids[J]. Journal of Food Engineering,2013,118(4):350-357.
[23] AUGER F,ANDR C,BOUVIER L,et al. Power requirement for mixing shear-thinning fluids with a planetary mixer[J]. Chemical Engineering & Technology,2015,38(9):1543-1549.