• Featured in Physics
  • Editors' Suggestion
  • Open Access

Flattened and Wrinkled Encapsulated Droplets: Shape Morphing Induced by Gravity and Evaporation

Davide Riccobelli, Hedar H. Al-Terke, Päivi Laaksonen, Pierangelo Metrangolo, Arja Paananen, Robin H. A. Ras, Pasquale Ciarletta, and Dominic Vella
Phys. Rev. Lett. 130, 218202 – Published 24 May 2023
Physics logo See synopsis: Gravity Alters the Shape of an Evaporating Droplet
PDFHTMLExport Citation

Abstract

We report surprising morphological changes of suspension droplets (containing class II hydrophobin protein HFBI from Trichoderma reesei in water) as they evaporate with a contact line pinned on a rigid solid substrate. Both pendant and sessile droplets display the formation of an encapsulating elastic film as the bulk concentration of solute reaches a critical value during evaporation, but the morphology of the droplet varies significantly: for sessile droplets, the elastic film ultimately crumples in a nearly flattened area close to the apex while in pendant droplets, circumferential wrinkling occurs close to the contact line. These different morphologies are understood through a gravito-elastocapillary model that predicts the droplet morphology and the onset of shape changes, as well as showing that the influence of the direction of gravity remains crucial even for very small droplets (where the effect of gravity can normally be neglected). The results pave the way to control droplet shape in several engineering and biomedical applications.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 29 November 2022
  • Accepted 7 April 2023

DOI:https://doi.org/10.1103/PhysRevLett.130.218202

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

Published by the American Physical Society

Physics Subject Headings (PhySH)

Polymers & Soft MatterFluid Dynamics

synopsis

Key Image

Gravity Alters the Shape of an Evaporating Droplet

Published 24 May 2023

Whether sitting or hanging, the surface of a protein-containing droplet changes as the water escapes, an effect researchers link to the pull of gravity.

See more in Physics

Authors & Affiliations

Davide Riccobelli1,*, Hedar H. Al-Terke2,3,*, Päivi Laaksonen4, Pierangelo Metrangolo5,2,3, Arja Paananen6, Robin H. A. Ras2,3, Pasquale Ciarletta1, and Dominic Vella7,†

  • 1MOX–Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
  • 2Department of Applied Physics, Aalto University School of Science, Espoo, Finland
  • 3Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, Espoo, Finland
  • 4HAMK Tech, Häme University of Applied Sciences, 13100 Hämeenlinna, Finland
  • 5Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, 20131 Milano, Italy
  • 6VTT Technical Research Centre of Finland Ltd, Tekniikantie 21, 02150 Espoo, Finland
  • 7Mathematical Institute, University of Oxford, Woodstock Road, Oxford OX2 6GG, United Kingdom

  • *These two authors contributed equally.
  • dominic.vella@maths.ox.ac.uk

Article Text

Click to Expand

Supplemental Material

Click to Expand

References

Click to Expand
Issue

Vol. 130, Iss. 21 — 26 May 2023

Reuse & Permissions
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 4.0 International license. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

×

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×