中国物理B ›› 2021, Vol. 30 ›› Issue (11): 114701-114701.doi: 10.1088/1674-1056/abf108

• • 上一篇    下一篇

Effect of Joule heating on the electroosmotic microvortex and dielectrophoretic particle separation controlled by local electric field

Bing Yan(严兵), Bo Chen(陈波), Yongliang Xiong(熊永亮), and Zerui Peng(彭泽瑞)   

  1. School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
  • 收稿日期:2021-02-09 修回日期:2021-03-16 接受日期:2021-03-23 出版日期:2021-10-13 发布日期:2021-11-03
  • 通讯作者: Bo Chen E-mail:chbo76@hust.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11572139).

Effect of Joule heating on the electroosmotic microvortex and dielectrophoretic particle separation controlled by local electric field

Bing Yan(严兵), Bo Chen(陈波), Yongliang Xiong(熊永亮), and Zerui Peng(彭泽瑞)   

  1. School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
  • Received:2021-02-09 Revised:2021-03-16 Accepted:2021-03-23 Online:2021-10-13 Published:2021-11-03
  • Contact: Bo Chen E-mail:chbo76@hust.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11572139).

摘要: Dielectrophoresis (DEP) technology has become important application of microfluidic technology to manipulate particles. By using a local modulating electric field to control the combination of electroosmotic microvortices and DEP, our group proposed a device using a direct current (DC) electric field to achieve continuous particle separation. In this paper, the influence of the Joule heating effect on the continuous separation of particles is analyzed. Results show that the Joule heating effect is caused by the local electric field, and the Joule heating effect caused by adjusting the modulating voltage is more significant than that by driving voltage. Moreover, a non-uniform temperature distribution exists in the channel due to the Joule heating effect, and the temperature is the highest at the midpoint of the modulating electrodes. The channel flux can be enhanced, and the enhancement of both the channel flux and temperature is more obvious for a stronger Joule heating effect. In addition, the ability of the vortices to trap particles is enhanced since a larger DEP force is exerted on the particles with the Joule heating effect; and the ability of the vortex to capture particles is stronger with a stronger Joule heating effect. The separation efficiency can also be increased because perfect separation is achieved at a higher channel flux. Parameter optimization of the separation device, such as the convective heat transfer coefficient of the channel wall, the length of modulating electrode, and the width of the channel, is performed.

关键词: dielectrophoresis, microvortices, Joule heating effect, particle separation

Abstract: Dielectrophoresis (DEP) technology has become important application of microfluidic technology to manipulate particles. By using a local modulating electric field to control the combination of electroosmotic microvortices and DEP, our group proposed a device using a direct current (DC) electric field to achieve continuous particle separation. In this paper, the influence of the Joule heating effect on the continuous separation of particles is analyzed. Results show that the Joule heating effect is caused by the local electric field, and the Joule heating effect caused by adjusting the modulating voltage is more significant than that by driving voltage. Moreover, a non-uniform temperature distribution exists in the channel due to the Joule heating effect, and the temperature is the highest at the midpoint of the modulating electrodes. The channel flux can be enhanced, and the enhancement of both the channel flux and temperature is more obvious for a stronger Joule heating effect. In addition, the ability of the vortices to trap particles is enhanced since a larger DEP force is exerted on the particles with the Joule heating effect; and the ability of the vortex to capture particles is stronger with a stronger Joule heating effect. The separation efficiency can also be increased because perfect separation is achieved at a higher channel flux. Parameter optimization of the separation device, such as the convective heat transfer coefficient of the channel wall, the length of modulating electrode, and the width of the channel, is performed.

Key words: dielectrophoresis, microvortices, Joule heating effect, particle separation

中图分类号:  (Electrokinetic effects)

  • 47.57.jd
47.61.-k (Micro- and nano- scale flow phenomena) 47.15.Rq (Laminar flows in cavities, channels, ducts, and conduits)