A new quality preserving polygonal mesh refinement algorithm for Virtual Element Methods

TL;DR

This paper introduces a novel polygonal mesh refinement algorithm that preserves quality and aims to enhance convergence and optimality in Virtual Element Methods for complex geometries.

Contribution

It proposes a new convex cell refinement method addressing convergence, quality preservation, and complexity bounds in polygonal mesh adaptivity.

Findings

Ensures quality preservation during mesh refinement.

Addresses convergence and optimality issues for polygonal adaptive methods.

Provides bounds on the number of unknowns relative to mesh cells.

Abstract

Mesh adaptivity is a useful tool for efficient solution to partial differential equations in very complex geometries. In the present paper we discuss the use of polygonal mesh refinement in order to tackle two common issues: first, adaptively refine a provided good quality polygonal mesh preserving quality, second, improve the quality of a coarse poor quality polygonal mesh during the refinement process on very complex domains. For finite element methods and triangular meshes, convergence of a posteriori mesh refinement algorithms and optimality properties have been widely investigated, whereas convergence and optimality are still open problems for polygonal adaptive methods. In this article, we propose a new refinement method for convex cells with the aim of introducing some properties useful to tackle convergence and optimality for adaptive methods. The key issues in refining convex general polygons are: a refinement dependent only on the marked cells for refinement at each refinement step; a partial quality improvement, or, at least, a non degenerate quality of the mesh during the refinement iterations; a bound of the number of unknowns of the discrete problem with respect to the number of the cells in the mesh. Although these properties are quite common for refinement algorithms of triangular meshes, these issues are still open problems for polygonal meshes