化工学报

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长短叶片复合型刚柔桨强化搅拌槽内流体混沌混合行为

刘作华1,3, 魏红军1,3, 熊黠1,3, 陶长元1,3, 王运东2, 程芳琴4   

  1. 1 重庆大学化学化工学院, 重庆 400044;
    2 清华大学化学工程系, 北京 100084;
    3 煤矿灾害动力学与控制国家重点实验室, 重庆大学, 重庆, 400044;
    4 山西大学资源与环境工程研究所, 山西 太原, 030006
  • 收稿日期:2020-03-04 修回日期:2020-05-18 出版日期:2023-04-17 发布日期:2020-05-25
  • 通讯作者: 刘作华(1973-),男,博士,教授,liuzuohua@cqu.edu.cn E-mail:liuzuohua@cqu.edu.cn
  • 作者简介:刘作华(1973-),男,博士,教授,liuzuohua@cqu.edu.cn
  • 基金资助:
    国家重点研发计划项目(2017YFB0603105);国家自然科学基金项目(21636004);重庆市教委科学技术研究计划项目重点项目(KJZD-M201900101);重庆市技术创新与应用示范专项产业类重点研发项目(cstc2018jszx-cyzdX0085)

Chaotic mixing performance enhanced by rigid-flexible impeller with long-short blades in stirred tank

LIU Zuohua1,3, WEI Hongjun1,3, XIONG Xia1,3, TAO Changyuan1,3, WANG Yundong2, CHENG Fangqin4   

  1. 1 School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China;
    2 Department of Chemical Engineering, Tsinghua University, Beijing 100084, China;
    3 State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China;
    4 Institute of Resources and Environment Engineering, Shanxi University, Taiyuan 030006, Shanxi, China
  • Received:2020-03-04 Revised:2020-05-18 Online:2023-04-17 Published:2020-05-25

摘要: 搅拌反应器中混合隔离区的存在是强化流体混合的主要障碍。打破搅拌槽中的对称性流场结构,破坏混合隔离区,可以提高流体混合效率。采用Matlab软件编程计算最大Lyapunov指数(LLE)和多尺度熵(MSE),比较了不同桨叶类型、柔性片长度、柔性片数量和桨叶离底高度以及转速对流体混合的影响。结果表明,长短叶片复合型刚柔桨(RF-LSB)桨叶通过刚柔耦合错位连接,柔性片的形变与随机振动对流体的非稳态扰动,使流场结构不稳定性和不对称性增强,强化了流体混合效果。当柔性片数量为3,搅拌转速为90 r/min时,长短叶片复合型刚柔桨(RF-LSB)体系比刚性桨和刚柔桨体系的LLE值分别提高了20.22%和7.98%;三种体系(长短叶片复合型刚柔桨(柔性片数量为3)、刚性桨和刚柔桨体系)的混合时间(θm)与单位体积功耗(Pv)呈指数型关系,当Pv相同时,长短叶片复合型刚柔桨体系(柔性片数量为3)的混合时间(θm)最小,表明长短叶片复合型刚柔桨(柔性片数量为3)更有利于流体混沌混合。

关键词: 长短叶片复合型刚柔桨, 最大Lyapunov指数, 混沌混合, 多尺度熵

Abstract: Isolated mixing regions exist widely in the stirred tank, which is a major obstacle for efficient mixing. Destroy the symmetrical flow field structure, is used to increase fluid mixing efficiency by reducing the isolated mixing regions. The largest Lyapunov exponents and the multi-scale entropy were computed by Matlab software. Meanwhile, the effects of different blade types, the length of flexible pieces, the number of flexible pieces, the distance between impeller and bottom on the mixing performance are analyzed of the different impeller speeds. The results show that the rigid-flexible impeller with long-short blades (RF-LSB) can enhance the flow field structure more unstable and asymmetric with deformation and random vibration of flexible pieces, destroy the symmetry flow in the process of fluid mixing, induce the asymmetric flow field, and make more fluid into the chaotic state. When at 90 r/min and three pieces of flexible, the LLE of the rigid-flexible impeller with long-short blades (RF-LSB) is larger than that of rigid impeller and rigid-flexible impeller. The LLE of the rigid-flexible impeller with long-short blades (RF-LSB) compared with the rigid impeller and rigid-flexible impeller increases 20.22% and 7.98% respectively. The mixing time (θm) of the three systems (rigid-flexible impeller with long-short blades (RF-LSB, three pieces), rigid impeller, rigid-flexible impeller) has an exponential relationship with the power consumption per unit volume (Pv). When Pv is constant, the mixing time (θm) of the rigid-flexible impeller with long-short blades (RF-LSB) system is the smallest. Results showed that the rigid-flexible impeller with long-short blades (RF-LSB, three pieces) is superior to rigid impeller and rigid-flexible impeller, which is more conducive to fluid chaotic mixing.

Key words: rigid-flexible impeller with long-short blades (RF-LSB), largest Lyapunov exponents, chaotic mixing, multi-scale entropy

中图分类号: 

  • TQ027.2
[1] Ramsay J, Simmons M J H, Ingram A, et al. Mixing of Newtonian and viscoelastic fluids using "butterfly" impellers[J]. Chemical Engineering Science, 2016, 139(1):125-141.
[2] Bulnes-abundis D, Alvarez M M. The simplest stirred tank for laminar mixing:Mixing in a vessel agitated by an off-centered angled disc[J]. AIChE Journal, 2013, 59(8):3092-3108.
[3] Reza A G, Abbasi M R, Bagheri A H, et al. Experimental and modeling evaluation of droplet size in immiscible liquid-liquid stirred vessel using various impeller designs[J]. Journal of the Taiwan Institute of Chemical Engineers, 2019, 100:26-36.
[4] Gu D Y, Cheng C, Liu Z H, et al. Numerical simulation of solid-liquid mixing characteristics in a stirred tank with fractal impellers[J]. Advanced Powder Technology, 2019, 30(10):2126-2138.
[5] Basbug S, Papadakis G, Vassilicos J C. Reduced power consumption in stirred vessels by means of fractal impellers[J]. AIChE Journal, 2018, 64(4):1485-1499.
[6] Hasal P, Fort I, Kratena J. Force Effects of the Macro-Instability of Flow Pattern on Radial Baffles in a Stirred Vessel With Pitched-Blade and Rushton Turbine Impellers[J]. Chemical Engineering Research and Design, 2004, 82(9):1268-1281.
[7] Devi T, Kumar B. Vortex depth analysis in an unbaffled stirred tank with concave blade impeller[J]. Chemistry & Chemical Technology, 2017, 11(3):301-307.
[8] Klenov O P, Noskov A S. Solid dispersion in the slurry reactor with multiple impellers[J]. Chemical Engineering Journal, 2011, 176-177:75-82.
[9] 刘作华, 唐巧, 王运东, 等. 刚柔组合搅拌桨增强混合澄清槽内流体宏观不稳定性[J]. 化工学报, 2014. 65(1):78-86. Liu Z H, Tang Q, Wang Y D, et al. Enhancement of macro-instability in mixer-settler with rigid-flexible impeller[J]. CIESC Journal, 2014, 65(1):78-86.
[10] Nie A, Gao Z M, Xue L, et al. Micromixing performance and the modeling of a confined impinging jet reactor/high speed disperser[J]. Chemical Engineering Science, 2018, 184:14-24.
[11] 邱发成, 刘作华, 刘仁龙, 等. 偏心射流-刚柔组合桨搅拌器内混沌混合行为研究[J]. 化工学报, 2018, 69(2):618-624. Qiu F C, Liu Z H, Liu R L, et al. Chaotic mixing performance in a rigid-flexible impeller stirred tank with eccentric air jet[J]. CIESC Journal, 2018, 69(2):618-624.
[12] Gu D Y, Liu Z H, Xu C L, et al. Solid-liquid mixing performance in a stirred tank with a double punched rigid-flexible impeller coupled with a chaotic motor[J]. Chemical Engineering & Processing:Process Intensification, 2017, 118:37-46.
[13] Woziwodzki S., Jedrzejczak L. Effect of eccentricity on laminar mixing in vessel stirred by double turbine impellers[J]. Chemical Engineering Research and Design, 2011, 89(11):2268-2278.
[14] Alvarez M M, Guzman A, Elias M. Experimental visualization of mixing pathologies in laminar stirred tank bioreactor[J]. Chemical Engineering Science, 2005, 60(9):2449-2457.
[15] Lamberto D J, Muzzio F J, Swanson P D. Computational analysis of regular and chaotic mixing in a stirred tank reactor[J]. Chemical Engineering Science, 2001, 56(12):4887-4889.
[16] 李挺, 贾卓泰, 张庆华, 等. 几种单层桨搅拌槽内宏观混合特性的比较[J]. 化工学报, 2019, 70(1):32-38. Li T, Jia Z T, Zhang Q H, et al. Comparison of macro-mixing characteristics of a stirred tank with different impellers[J]. CIESC Journal, 2019, 70(1):32-38.
[17] Yang F L, Zhou S J, An X H. Gas-liquid hydrodynamics in a vessel stirred by dual dislocated-blade Rushton impellers[J]. Chinese Journal of Chemical Engineering, 2015, 23(11):1746-1754.
[18] 潘翔. 长桨短叶片复合搅拌桨釜内流动特性和放大过程气液传质性能研究[D]. 江苏:东南大学, 2017. Pan X. Investigation on Fluid Flow Characteristics and Gas-Liquid Mass Transfer Performance Along Scale-up in Stirred Tanks with a Long-Short Blades Agitator[D]. Jiangsu:Southeast University, 2017.
[19] 刘作华, 孙瑞祥, 王运东, 等. 刚-柔组合桨强化流体混沌混合[J]. 化工学报, 2014, 65(9):3340-3349. Liu Z H, Sun R X, Wang Y D, et al. Chaotic mixing intensified by rigid-flexible coupling impeller[J]. CIESC Journal, 2014, 65(9):3340-3349.
[20] 刘作华, 曾启琴, 杨鲜艳, 等. 刚柔组合搅拌桨与刚性桨调控流场结构的对比[J]. 化工学报, 2014, 65(6):2078-2084. Liu Z H, Zeng Q Q, Yang X Y, et al. Flow field structure with rigid-flexible impeller and rigid impeller[J]. CIESC Journal, 2014, 65(6):2078-2084.
[21] 刘作华, 陈超, 刘仁龙, 等. 刚柔组合搅拌桨强化搅拌槽中流体混沌混合[J]. 化工学报, 2014, 65(1):61-70. Liu Z H, Chen C, Liu R L, et al. Chaotic mixing enhanced by rigid-flexible impeller in stirred vessel[J]. CIESC Journal, 2014, 65(1):61-70.
[22] 熊黠, 刘作华, 谷德银, 等. 刚柔组合桨强化粉煤灰酸浸搅拌槽内固液混沌混合[J]. 化工学报, 2019, 70(5):1693-1701. Xiong X, Liu Z H, Gu D Y, et al. Chaotic mixing process of fly ash in acid leaching tank intensified by rigid-flexible impeller[J]. CIESC Journal, 2019, 70(5):1693-1701.
[23] Liang Y Y, Shi D E, Xu B H, et al. Turbulent flow field in a stirred vessel agitated by an Impeller with flexible blades[J]. AIChE Journal, 2018, 64(11):4148-4161.
[24] Vasconcelos J M T, Orvalho S C P, Rodrigues A M A F, et al. Effect of blade shape on the performance of six-bladed disk turbine impellers[J]. Industrial & Engineering Chemistry Research, 2000; 39(1):203-213.
[25] Steiros K, Bruce P J K, Buxton O R H, et al. Power consumption and form drag of regular and fractal-shaped turbines in a stirred tank[J]. AIChE Journal, 2017, 63(2):843-854.
[26] Ascanio G. Mixing time in stirred vessels:A review of experimental techniques[J]. Chinese Journal of Chemical Engineering, 2015, 23(7):1065-1076.
[27] Rosenstein M T, Collins J J, Luca C J D, et al. A practical method for calculating largest Lyapunov exponents from small data sets[J]. Physica D:Nonlinear Phenomena, 1993, 65(1):117-134.
[28] Wolf A, Swift J B, Swinney H L, et al. Determining Lyapunov exponents from a time series[J]. Physica D:Nonlinear Phenomena, 1985, 16(3):285-317.
[29] Deng K, Li J, Yu S. Dynamics analysis and synchronization of a new chaotic attractor[J]. Optik-International Journal for Light and Electron Optics, 2014, 125(13):3071-3075.
[30] Hu H N, Liu D W. The Judgment of Chaotic Detection System's State Based on the Lyapunov Exponent[J]. Procedia Engineering, 2012, 29:2894-2898.
[31] Costa M, Healey J A. Multiscale entropy analysis of complex heart rate dynamics:discrimination of age and heart failure effects[C]//Murray A, Computers in Cardiology, 30th Annual Meeting on Computers in Cardiology. Greece:Institute of Electrical and Electronics Engineers Computer Society, 2003:705-708.
[32] Costa M, Goldberger A L, Peng C K. Multiscale entropy analysis of complex physiologic time series[J]. Physical Review Letters, 2002, 89(6):68102.
[33] Nikulin V V, Brismar T. Comment on "Multiscale Entropy Analysis of Complex Physiologic Time Series"[J]. Physical Review Letters, 2004, 92(8):89803.
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