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arXiv · 2304.00063

Quantitative study of the stabilization parameter in the virtual element method

Alessandro Russo·N. Sukumar
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Abstract

The choice of stabilization term is a critical component of the virtual element method (VEM). However, the theory of VEM provides only asymptotic guidance for selecting the stabilization term, which ensures convergence as the mesh size approaches zero, but does not provide a unique prescription for its exact form. Thus, the selection of a suitable stabilization term is often guided by numerical experimentation and analysis of the resulting solution, including factors such as stability, accuracy, and efficiency. In this paper, we establish a new link between VEM and generalized barycentric coordinates, in particular isoparametric finite elements as a specific case. This connection enables the interpretation of the stability as the energy of a particular function in the discrete space, commonly known as the `hourglass mode.' Through this approach, this study sheds light on how the virtual element solution depends on the stabilization term, providing insights into the behavior of the method in more general scenarios.

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Alessandro Russo, N. Sukumar. 2023-03-31. Quantitative study of the stabilization parameter in the virtual element method. https://arxiv.org/abs/2304.00063

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