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Theory of Shape-Shifting Droplets.
Pierre A Haas1, Raymond E Goldstein1, Stoyan K Smoukov2
1Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, United Kingdom.
Physical Review Letters
|March 11, 2017
Summary
Cooled oil droplets transform into flat, polygonal shapes due to phase transitions and surface tension. This study models these geometric changes and predicts droplet evolution, including protrusions and punctures.
Area of Science:
- Fluid dynamics
- Materials science
- Physical chemistry
Background:
- Cooled oil emulsion droplets exhibit shape transformations.
- These changes are driven by partial phase transitions and surface tension.
Purpose of the Study:
- To theoretically model the geometric competition between phase transitions and surface tension in oil droplets.
- To explain the observed sequence of flattened shapes and their statistics.
Main Methods:
- Theoretical modeling of planar polygons.
- Analysis of 2D and simplified 3D droplet structures.
- Investigating geometric competition and topological transitions.
Main Results:
- The model qualitatively reproduces the observed droplet shapes and statistics.
- Identified the interplay between phase transition and surface tension in shaping droplets.
- Analyzed the formation of vertex protrusions and polygon puncturing.
Conclusions:
- The theoretical framework explains the observed polygonal shapes of cooled oil droplets.
- The model provides insights into droplet evolution, including 3D structural changes and topological events.
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