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arXiv · 2311.04810

Finite Element Methods for the Stretching and Bending of Thin Structures with Folding

Andrea Bonito·Diane Guignard·Angelique Morvant
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Abstract

In [Bonito et al., J. Comput. Phys. (2022)], a local discontinuous Galerkin method was proposed for approximating the large bending of prestrained plates, and in [Bonito et al., IMA J. Numer. Anal. (2023)] the numerical properties of this method were explored. These works considered deformations driven predominantly by bending. Thus, a bending energy with a metric constraint was considered. We extend these results to the case of an energy with both a bending component and a nonconvex stretching component, and we also consider folding across a crease. The proposed discretization of this energy features a continuous finite element space, as well as a discrete Hessian operator. We establish the $\Gamma$-convergence of the discrete to the continuous energy and also present an energy-decreasing gradient flow for finding critical points of the discrete energy. Finally, we provide numerical simulations illustrating the convergence of minimizers and the capabilities of the model.

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Andrea Bonito, Diane Guignard, Angelique Morvant. 2023-11-08. Finite Element Methods for the Stretching and Bending of Thin Structures with Folding. https://arxiv.org/abs/2311.04810

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