力学学报 ›› 2018, Vol. 50 ›› Issue (2): 254-262.doi: 10.6052/0459-1879-17-291

• 流体力学 • 上一篇    下一篇

扩展腔对方波型微混合器混合性能的影响研究

刘赵淼2), 王文凯, 逄燕   

  1. 北京工业大学机械工程与应用电子技术学院,北京 100124
  • 收稿日期:2017-10-18 修回日期:2018-01-26 出版日期:2018-03-18 发布日期:2018-04-17
  • 作者简介:2)赵西增,教授,主要研究方向:波浪和建筑物的相互作用. E-mail: xizengzhao@zju.edu.cn
  • 基金资助:

    1)国家自然科学基金 (51679212) 和浙江省杰出青年基金 (LR16E090002)资助项目.

INFLUENCE OF EXPANDED CAVITY ON MIXING PERFORMANCE OF SQUARE-WAVE MICRO-MIXER 1)

Liu Zhaomiao2), Wang Wenkai, Pang Yan   

  1. (College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, China)
  • Received:2017-10-18 Revised:2018-01-26 Online:2018-03-18 Published:2018-04-17

摘要:

微混合器凭借节约试剂、混合强度高和易于集成等优点,在材料合成、医药制备和生化检测等领域中具有广泛的应用. 为了进一步提高混合性能,保证混合过程的安全性及生化反应结果的准确性,设计了一种带扩展腔的新型方波型微混合器. 在综合考虑混合强度和压降的前提下,通过实验研究和数值模拟分析了窄缝宽度、窄缝长度和扩展腔高度对微混合器混合性能的影响并得到了不同雷诺数Re条件下的最优结构参数. 与方波型微混合器的混合性能进行比较,发现Re?5时,带扩展腔的方波型微混合器的混合强度更高,其中Re=20时两者混合强度相差最多,可达12%. 在相同Re下,带扩展腔的方波型微混合器的压降要低于方波型微混合器. 对带扩展腔的方波型微混合器进行内部流场分析,发现扩展腔结构能在流体层流状态的基础上引入涡流,使通道中流体的流动状态发生改变、对流增强,进而混合性能提高.

关键词:

微混合器|混合强度|压降|结构优化|数值模拟

Abstract:

Micro-mixer has great application potentials in many fields such as material synthesis, pharmaceutical preparation and biochemical detection due to its advantages of saving reagents, higher mixing index and easy integration. In order to further improve the mixing performance, to ensure the safety of the mixing process and the accuracy of the biochemical reaction results, a new square wave micro-mixer with extended cavity was designed. Under the premise of considering the mixing index and pressure drop, the effects of the width of slit, the length of slit, and the height of extended cavity on the mixing performance of micro-mixer were analyzed by experiment and simulation. The optimal structural parameters were achieved under different Reynolds number (Re). Compared with the square-wave micro-mixer, the mixing strength of the square-wave micro-mixer with the extended cavity is higher when Re?5. Moreover, the gap of mixing index between two square-wave micro-mixer reaches maximum, up to 12%, at Re=20. Under the same Reynolds number, the pressure drop of the square-wave micro-mixer with the extended cavity is lower than that of the square-wave micro-mixer. Meanwhile, the analysis for the internal flow field of the square-wave micro-mixer with the extended cavity was carried out. It is found that the eddy current is introduced on the basis of the laminar flow state of the fluid because of the existence of the extended cavity structure, which means the change of the flow state of the fluid in the channel and the enhancement of convection effect, thus the mixing performance is further improved.

Key words:

micro-mixer|mixing index|pressure drop|structural optimization|numerical simulation

中图分类号: 

  • O35