Flow Structure near Three Phase Contact Line of Low-Contact-Angle Evaporating Droplets
Fuente:
arXiv
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866911760305356800 |
|---|---|
| author | Wang, Zhenying Karapetsas, George Valluri, Prashant Inoue, Chihiro |
| author_facet | Wang, Zhenying Karapetsas, George Valluri, Prashant Inoue, Chihiro |
| contents | Flow structure near three phase contact line (TPCL) of evaporating liquids plays a significant role in liquid wetting and dewetting, liquid film evaporation and boiling, etc. Despite the wide focus it receives, the interacting mechanisms therein remain elusive and in specific cases, controversial. Here, we reveal the profile of internal flow and elucidate the dominating mechanisms near TPCL of evaporating droplets, using mathematical modelling, microPIV, and infrared thermography. We indicate that for less volatile liquids such as butanol, the flow pattern is dominated by capillary flow. With increasing liquid volatility, e.g., alcohol, the effect of evaporation cooling, under conditions, induces interfacial temperature gradient with cold droplet apex and warm edge. The temperature gradient leads to Marangoni flow that competes with outwarding capillary flow, resulting in the reversal of interfacial flow and the formation of a stagnation point near TPCL. The spatiotemporal variations of capillary velocity and Marangoni velocity are further quantified by mathematically decomposing the tangential velocity of interfacial flow. The conclusions can serve as a theoretical base for explaining deposition patterns from colloidal suspensions, and can be utilized as a benchmark in analyzing more complex liquid systems. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2401_09950 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Flow Structure near Three Phase Contact Line of Low-Contact-Angle Evaporating Droplets Wang, Zhenying Karapetsas, George Valluri, Prashant Inoue, Chihiro Fluid Dynamics Soft Condensed Matter Flow structure near three phase contact line (TPCL) of evaporating liquids plays a significant role in liquid wetting and dewetting, liquid film evaporation and boiling, etc. Despite the wide focus it receives, the interacting mechanisms therein remain elusive and in specific cases, controversial. Here, we reveal the profile of internal flow and elucidate the dominating mechanisms near TPCL of evaporating droplets, using mathematical modelling, microPIV, and infrared thermography. We indicate that for less volatile liquids such as butanol, the flow pattern is dominated by capillary flow. With increasing liquid volatility, e.g., alcohol, the effect of evaporation cooling, under conditions, induces interfacial temperature gradient with cold droplet apex and warm edge. The temperature gradient leads to Marangoni flow that competes with outwarding capillary flow, resulting in the reversal of interfacial flow and the formation of a stagnation point near TPCL. The spatiotemporal variations of capillary velocity and Marangoni velocity are further quantified by mathematically decomposing the tangential velocity of interfacial flow. The conclusions can serve as a theoretical base for explaining deposition patterns from colloidal suspensions, and can be utilized as a benchmark in analyzing more complex liquid systems. |
| title | Flow Structure near Three Phase Contact Line of Low-Contact-Angle Evaporating Droplets |
| topic | Fluid Dynamics Soft Condensed Matter |
| url | https://arxiv.org/abs/2401.09950 |