仿柳叶形静态混合器的流动及混合特性

doi:10.11949/j.issn.0438-1157.20170755

摘要/Abstract

摘要：

对仿柳叶形静态混合器内混合气流进行了速度场与浓度场的试验研究，结果表明该混合器内速度场与浓度场偏差均达到了非常理想的效果（优于国家标准偏差值）。同时采用CFD软件对该静态混合器内的流场进行了数值模拟，试验与模拟的数值结果以及两者的浓度云图分布都有着较好的一致性。随后的研究结果表明：在混合元件尾迹区域出现了纵向涡和发卡涡来促进混合；在经过混合元件区域时因为湍流动能耗散率增加形成的高湍流动能耗散率区能够使物质交换更加频繁；整个静态混合器的流动阻力也主要发生在该区域，随之出现的返混现象也在一定程度上加强了混合效果。

关键词: 仿柳叶形, 气流返混, 流动混合特性, 混合, 静态混合器

Abstract:

Gas mixing flow in willow leaf-like static mixer was studied on both velocity and concentration field. The experimental results showed that deviations of velocity and concentration fields were reached to ideal range and were better than those of national standards. CFD simulation on the mixer flow field exhibited good consistencies in numerical values and distribution of concentration cloud diagram between experiment and simulation. Subsequent studies showed that mixing was promoted by longitudinal and hairpin vortices appeared in tailing wake zone of the mixing element. When gas was passing through the mixing element, a high turbulent flow energy dissipation region formed by turbulence-induced increase of kinetic energy dissipation rate could drive much frequent material transfer. Flow resistance of the entire static mixer also occurred mainly in this high energy dissipation region. To some extent, back mixing after the high energy dissipation region strengthened mixing effect.

Key words: willow leaf-like, airflow back mixing, flow mixing characteristics, mixing, static mixer

中图分类号:

TK223.1

傅鑫亮, 闫志勇. 仿柳叶形静态混合器的流动及混合特性[J]. 化工学报, 2017, 68(12): 4600-4606.

FU Xinliang, YAN Zhiyong. Flow and mixing characteristics in willow leaf-like static mixer[J]. CIESC Journal, 2017, 68(12): 4600-4606.

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