中国物理B ›› 2020, Vol. 29 ›› Issue (1): 14701-014701.doi: 10.1088/1674-1056/ab5782

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Evaporation of saline colloidal droplet and deposition pattern

Hong-Hui Sun(孙弘辉), Wei-Bin Li(李伟斌), Wen-Jie Ji(纪文杰), Guo-Liang Dai(戴国亮), Yong Huan(郇勇), Yu-Ren Wang(王育人), Ding Lan(蓝鼎)   

  1. 1 National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China;
    2 State Key Laboratory of Nonlinear Mechanics(LNM), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China;
    3 School of Engineering Sciences, University of Chinese Academy of Sciences, Beijing 100049 China
  • 收稿日期:2019-09-24 修回日期:2019-10-28 出版日期:2020-01-05 发布日期:2020-01-05
  • 通讯作者: Ding Lan E-mail:landing@imech.ac.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11472275 and U1738118), the Chinese Academy of Sciences Key Technology Talent Program, and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB22040301).

Evaporation of saline colloidal droplet and deposition pattern

Hong-Hui Sun(孙弘辉)1,3, Wei-Bin Li(李伟斌)1,3, Wen-Jie Ji(纪文杰)1,2, Guo-Liang Dai(戴国亮)1,3, Yong Huan(郇勇)2,3, Yu-Ren Wang(王育人)1,3, Ding Lan(蓝鼎)1,3   

  1. 1 National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China;
    2 State Key Laboratory of Nonlinear Mechanics(LNM), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China;
    3 School of Engineering Sciences, University of Chinese Academy of Sciences, Beijing 100049 China
  • Received:2019-09-24 Revised:2019-10-28 Online:2020-01-05 Published:2020-01-05
  • Contact: Ding Lan E-mail:landing@imech.ac.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11472275 and U1738118), the Chinese Academy of Sciences Key Technology Talent Program, and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB22040301).

摘要: The dynamic process of the evaporation and the desiccation of sessile saline colloidal droplets, and their final deposition are investigated. During the evaporation, the movement of the colloidal particles shows a strong dependence on the salt concentration and the droplet shape. The final deposition pattern indicates a weakened coffee-ring effect in this mixed droplet system. The microscopic observation reveals that as evaporation proceeds, the particle motion trail is affected by the salt concentration of the droplet boundary. The Marangoni flow, which is induced by surface tension gradient originating from the local evaporative peripheral salt enrichment, suppresses the compensation flow towards the contact line of the droplet. The inhomogeneous density and concentration field induced by evaporation or crystallization can be the major reason for various micro-flows. At last stage, the distribution and crystallization of NaCl are affected by the colloidal particles during the drying of the residual liquid film.

关键词: saline droplet, evaporation, deposition pattern, disease diagnosis

Abstract: The dynamic process of the evaporation and the desiccation of sessile saline colloidal droplets, and their final deposition are investigated. During the evaporation, the movement of the colloidal particles shows a strong dependence on the salt concentration and the droplet shape. The final deposition pattern indicates a weakened coffee-ring effect in this mixed droplet system. The microscopic observation reveals that as evaporation proceeds, the particle motion trail is affected by the salt concentration of the droplet boundary. The Marangoni flow, which is induced by surface tension gradient originating from the local evaporative peripheral salt enrichment, suppresses the compensation flow towards the contact line of the droplet. The inhomogeneous density and concentration field induced by evaporation or crystallization can be the major reason for various micro-flows. At last stage, the distribution and crystallization of NaCl are affected by the colloidal particles during the drying of the residual liquid film.

Key words: saline droplet, evaporation, deposition pattern, disease diagnosis

中图分类号:  (Capillary and thermocapillary flows)

  • 47.55.nb
47.55.np (Contact lines) 45.70.Qj (Pattern formation)