We review different (reduced) models for thin structures using bending as principal mechanism to undergo large deformations. Each model consists in the minimization of a fourth order energy, potentially subject to a nonconvex constraint. Equilibrium deformations are approximated using local discontinuous Galerkin (LDG) finite elements. The design of the discrete energies relies on a discrete Hessian operator defined on discontinuous functions with better approximation properties than the piecewise Hessian. Discrete gradient flows are put in place to drive the minimization process. They are chosen for their robustness and ability to preserve the nonconvex constraint. Several numerical experiments are presented to showcase the large variety of shapes that can be achieved with these models.
翻译:我们用弯曲作为进行大规模变形的主要机制,对薄质结构的不同(减少)模型进行审查。每种模型都包含将可能受到非电解质制约的第四等能量最小化。 平衡变形使用局部不连续的加勒金(LDG)有限元素进行近似。 离散能量的设计依赖于一个离散的赫西恩操作员, 其不连续功能的近似性比小行星赫西安更强。 设置了分解的梯度流来驱动最小化过程。 选择它们是为了显示其坚固性和保存非电解质制约的能力。 提供了几个数字实验, 以展示这些模型能够实现的多种形状 。