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arXiv · 1508.06146

Wrinkling reveals a new isometry of pressurized elastic shells

Dominic Vella·Hamid Ebrahimi·Ashkan Vaziri·Benny Davidovitch
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Abstract

We consider the point indentation of a pressurized, spherical elastic shell. Previously it was shown that such shells wrinkle once the indentation reaches a threshold value. Here, we study the behaviour of this system beyond the onset of instability. We show that rather than simply approaching the classical `mirror-buckled' shape, the wrinkled shell approaches a new, universal shape that reflects a nontrivial type of isometry. For a given indentation depth, this ``asymptotic isometry", which is only made possible by wrinkling, is reached in the doubly asymptotic limit of weak pressure and vanishing shell thickness.

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Dominic Vella, Hamid Ebrahimi, Ashkan Vaziri, Benny Davidovitch. 2015-08-25. Wrinkling reveals a new isometry of pressurized elastic shells. https://doi.org/10.1209/0295-5075/112/24007

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