Encoding quadrupolar capillary information into saddle-shaped objects for self-assembly
Phys. Rev. Fluids 10, 104003 – Published 14 October, 2025
DOI: https://doi.org/10.1103/f3tr-kby1
Abstract
The “Cheerios effect,” which describes the capillary interaction between spherical particles at a liquid interface, has traditionally been limited to simple self-assembling structures. Our study addresses the need for more complex assemblies by exploring specific particle geometries. We introduce a theoretical model to describe the interaction potential between quadrupolar objects at the mesoscale, which reveals that both side-by-side and end-to-end long-range attractions can be achieved under specific capillary and geometrical conditions—a phenomenon we term the “Pringles effect.” We experimentally validate our model's predictions by encoding this specific capillary information into 3D-printed curved ellipses, which mimic the surface geometry of Pringles crisps. This approach showcases the potential for complex self-assembling mesoscale structures through precise control over capillary-driven interactions.
