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arXiv · 1807.11270

Large deformation mixed finite elements for smart structures

Astrid S. Pechstein
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Abstract

Recently, "Tangential Displacement Normal Normal Stress" (TDNNS) elements were introduced for small-deformation piezoelectric structures. Benefits of these ele- ments are that they are free from shear locking in thin structures and volume locking for nearly incompressible materials. We extend these elements to the large defor- mation case for electro-active polymers in the framework of an updated Lagrangian method. We observe that convergence does not deteriorate as the material becomes nearly incompressible with growing Lam\'e parameter $\lambda$, and that the discretization of slender structures by flat volume elements is feasible. The elements are freely available in the open source software package Netgen/NGSolve.

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Astrid S. Pechstein. 2018-07-30. Large deformation mixed finite elements for smart structures. https://arxiv.org/abs/1807.11270

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