一种连续流反应器内射流耦合搅拌流的混合特性

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摘要连续式搅拌反应器采用连续化工艺,可以保证生产过程的连续性,相较于传统反应器而言,连续式反应器内流场更复杂,进料口射流对于流场的影响较为明显。对传统的双层搅拌桨结构的微波反应釜进行连续化改造,基于计算流体力学CFD(Computational Fluid Dynamics)方法对不同射流方案下反应器内醇油混合液的流动及混合特性进行了数值模拟,得到反应器内混合液的流动特性和混合时间特征。结果表明:射流通过直接影响射流区的流场和改变反应器内的循环涡流位置间接影响全局流动;射流方向对于反应器内流型影响更大,逆时针射流时反应器内的速度梯度大,流体之间的剪切作用更强,混合性能最佳,相较于传统的间歇式搅拌反应器,混合时间缩短了33%。

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	韩太柏
	金光远
	邹鹏程
	祝玉莲
	宋春芳
	李臻峰
	陈海英

关键词：连续流反应器射流停留时间混合特性数值模拟

Abstract： By using the continuous processing technique, continuous stirred tank reactor (CSTR) is able to maintain the continuity of the production process. Compared with traditional reactor, the inner flow field in CSTR is more complex, and CSTR shows a more significant effect of the feed inlet jet on the flow field. In this paper, the traditional microwave reactor with double agitator structure was reformed with the continuous technique. Through date stimulation method, based on CFD (Computational Fluid Dynamics), the features of both flowing and mixing time in CSTR under different jet schemes were obtained. The result suggested that the jet flow affects directly not only the flow field in the flow region but also the position of the circulating eddy current and in turn affects the flow globally in the reactor. In addition, the jet direction has a greater effect on the flow pattern in the reactor. When jetting counterclockwise, the velocity gradient in the reactor got larger, the shearing effect between the fluids got stronger, thus the mixing performed the best. Compared with the traditional batch-type reactor, the time taken by CSTR was saved by 33%.

Keywords： continuous flow reactor jet residence time mixing characteristics numerical simulation

Received 2021-09-03;

Fund:国家自然科学基金(21606109)。

Corresponding Authors: 金光远,副教授,E-mail:gyuanjin@jiangnan.edu.cn Email: gyuanjin@jiangnan.edu.cn

About author: 韩太柏(1995-),男,硕士研究生,现从事流体仿真与分析计算方面的研究。

引用本文:

韩太柏, 金光远, 邹鹏程, 祝玉莲, 宋春芳, 李臻峰, 陈海英.一种连续流反应器内射流耦合搅拌流的混合特性[J]. 化学工业与工程, 2023,40(2): 133-142

HAN Taibai, JIN Guangyuan, ZOU Pengcheng, ZHU Yulian, SONG Chunfang, LI Zhenfeng, CHEN Haiying.Mixing characteristics of continuous flow reactor coupled with jet and mechanical stirring[J]. Chemcial Industry and Engineering, 2023,40(2): 133-142

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