Accurate matrix-free time-domain method with traditional vector bases in unstructured meshes

In this paper, we develop a new time-domain method that is naturally matrix free and independent of element shape used for discretization. No extra modification on traditional vector bases is required. Its implementation is straightforward. The accuracy and stability of the proposed method are shown to be guaranteed. Numerical experiments on a variety of unstructured tetrahedral meshes have validated the accuracy and generality of the proposed method.