Conditioning of Finite Volume Element Method for Diffusion Problems with General Simplicial Meshes
Provides theoretical conditioning bounds for finite volume element discretizations on general meshes, which is important for practitioners solving diffusion problems with complex geometries.
The paper analyzes the conditioning of the finite volume element method for diffusion equations on arbitrary simplicial meshes, deriving an upper bound for the condition number that depends on mesh size and nonuniformity. Numerical results in 1D, 2D, and 3D confirm the theoretical findings.
The conditioning of the linear finite volume element discretization for general diffusion equations is studied on arbitrary simplicial meshes. The condition number is defined as the ratio of the maximal singular value of the stiffness matrix to the minimal eigenvalue of its symmetric part. This definition is motivated by the fact that the convergence rate of the generalized minimal residual method for the corresponding linear systems is determined by the ratio. An upper bound for the ratio is established by developing an upper bound for the maximal singular value and a lower bound for the minimal eigenvalue of the symmetric part. It is shown that the bound depends on three factors, the number of the elements in the mesh, the mesh nonuniformity measured in the Euclidean metric, and the mesh nonuniformity measured in the metric specified by the inverse diffusion matrix. It is also shown that the diagonal scaling can effectively eliminates the effects from the mesh nonuniformity measured in the Euclidean metric. Numerical results for a selection of examples in one, two, and three dimensions are presented.