On the stabilization of a virtual element method for an acoustic vibration problem
Linda Alzaben, Daniele Boffi, Andreas Dedner, Lucia Gastaldi
TL;DR
This work develops a rigorous framework for the convergence of a virtual element method for an acoustic vibration eigenproblem, examining how stabilization influences spectral accuracy. By recasting the problem in a mixed Kikuchi-type formulation and leveraging the discrete compactness property, the authors establish conditions under which stabilized VEM schemes converge and, in some cases, remain stabilization-free, notably for the lowest-order triangular elements. They prove EDk/WA/SA criteria imply uniform convergence of the discrete solution operator to the continuous one and demonstrate that stabilization can be unnecessary in several practical scenarios. Numerical experiments on rectangular and L-shaped domains corroborate the theory, showing parameter-free accuracy for certain meshes and orders, while highlighting mesh-dependent behavior and instances where stabilization restores optimal convergence.
Abstract
In this paper we introduce an abstract setting for the convergence analysis of the virtual element approximation of an acoustic vibration problem. We discuss the effect of the stabilization parameters and remark that in some cases it is possible to achieve optimal convergence without the need of any stabilization. This statement is rigorously proved for lowest order triangular element and supported by several numerical experiments.
