Bouncing-to-wetting transition of water droplets impacting soft solids
Soft surfaces impacted by liquid droplets trap more air underneath than their rigid counterparts. The extended lifetime of the air film not only facilitates bouncing behaviours of the impacting droplets but also increases the possibility of interactions between the air film itself and the air cavity...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2022
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/159657 |
| _version_ | 1811697228591398912 |
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| author | Mitra, Surjyasish Vo, Quoc Tran, Tuan |
| author2 | School of Physical and Mathematical Sciences |
| author_facet | School of Physical and Mathematical Sciences Mitra, Surjyasish Vo, Quoc Tran, Tuan |
| author_sort | Mitra, Surjyasish |
| collection | NTU |
| description | Soft surfaces impacted by liquid droplets trap more air underneath than their rigid counterparts. The extended lifetime of the air film not only facilitates bouncing behaviours of the impacting droplets but also increases the possibility of interactions between the air film itself and the air cavity formed inside the droplets by capillary waves. Such interactions may cause rupture of the trapped air film by a so-called dimple inversion phenomenon and suppress bouncing. In this work, we systematically investigate the relationship between air cavity collapse and air film rupture for water droplets impacting soft, hydrophobic surfaces. By constructing a bouncing-to-wetting phase diagram based on the rupturing dynamics of the trapped air film, we observe that the regime in which air film rupture is induced by dimple inversion consistently separates the bouncing regime and the one in which wetting is caused by random rupture. We also found that air film rupture by dimple inversion in-turn affects both the collapsing dynamics of the air cavity and the resulting high-speed jet. We then provide a detailed characterisation of the collapsing dynamics of the air cavity and subsequent jetting. |
| first_indexed | 2024-10-01T07:51:55Z |
| format | Journal Article |
| id | ntu-10356/159657 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T07:51:55Z |
| publishDate | 2022 |
| record_format | dspace |
| spelling | ntu-10356/1596572022-06-29T06:04:33Z Bouncing-to-wetting transition of water droplets impacting soft solids Mitra, Surjyasish Vo, Quoc Tran, Tuan School of Physical and Mathematical Sciences School of Mechanical and Aerospace Engineering Science::Physics Rupturing Dynamics Collapsing Dynamics Soft surfaces impacted by liquid droplets trap more air underneath than their rigid counterparts. The extended lifetime of the air film not only facilitates bouncing behaviours of the impacting droplets but also increases the possibility of interactions between the air film itself and the air cavity formed inside the droplets by capillary waves. Such interactions may cause rupture of the trapped air film by a so-called dimple inversion phenomenon and suppress bouncing. In this work, we systematically investigate the relationship between air cavity collapse and air film rupture for water droplets impacting soft, hydrophobic surfaces. By constructing a bouncing-to-wetting phase diagram based on the rupturing dynamics of the trapped air film, we observe that the regime in which air film rupture is induced by dimple inversion consistently separates the bouncing regime and the one in which wetting is caused by random rupture. We also found that air film rupture by dimple inversion in-turn affects both the collapsing dynamics of the air cavity and the resulting high-speed jet. We then provide a detailed characterisation of the collapsing dynamics of the air cavity and subsequent jetting. Agency for Science, Technology and Research (A*STAR) Nanyang Technological University This study is supported by the Nanyang Technological University (NTU) and A*STAR (SERC Grant No. 1523700102). S.M. is supported by NTU Research Scholarship. 2022-06-29T06:04:33Z 2022-06-29T06:04:33Z 2021 Journal Article Mitra, S., Vo, Q. & Tran, T. (2021). Bouncing-to-wetting transition of water droplets impacting soft solids. Soft Matter, 17(24), 5969-5977. https://dx.doi.org/10.1039/d1sm00339a 1744-683X https://hdl.handle.net/10356/159657 10.1039/d1sm00339a 34047748 2-s2.0-85108692383 24 17 5969 5977 en SERC 1523700102 Soft Matter © 2021 The Royal Society of Chemistry. All rights reserved. |
| spellingShingle | Science::Physics Rupturing Dynamics Collapsing Dynamics Mitra, Surjyasish Vo, Quoc Tran, Tuan Bouncing-to-wetting transition of water droplets impacting soft solids |
| title | Bouncing-to-wetting transition of water droplets impacting soft solids |
| title_full | Bouncing-to-wetting transition of water droplets impacting soft solids |
| title_fullStr | Bouncing-to-wetting transition of water droplets impacting soft solids |
| title_full_unstemmed | Bouncing-to-wetting transition of water droplets impacting soft solids |
| title_short | Bouncing-to-wetting transition of water droplets impacting soft solids |
| title_sort | bouncing to wetting transition of water droplets impacting soft solids |
| topic | Science::Physics Rupturing Dynamics Collapsing Dynamics |
| url | https://hdl.handle.net/10356/159657 |
| work_keys_str_mv | AT mitrasurjyasish bouncingtowettingtransitionofwaterdropletsimpactingsoftsolids AT voquoc bouncingtowettingtransitionofwaterdropletsimpactingsoftsolids AT trantuan bouncingtowettingtransitionofwaterdropletsimpactingsoftsolids |