An initial-boundary value problem for a time-fractional diffusion equation is discretized in space, using continuous piecewise-linear finite elements on a domain with a re-entrant corner. Known error bounds for the case of a convex domain break down, because the associated Poisson equation is no longer \(H^{2}\) -regular. In particular, the method is no longer second-order accurate if quasi-uniform triangulations are used. We prove that a suitable local mesh refinement about the re-entrant corner restores second-order convergence. In this way, we generalize known results for the classical heat equation. doi:10.1017/S1446181116000365
@article{10940, title = {Finite element approximation of a time-fractional diffusion problem for a domain with a re-entrant corner}, journal = {ANZIAM Journal}, volume = {58}, year = {2017}, doi = {10.21914/anziamj.v59i0.10940}, language = {EN}, url = {http://dml.mathdoc.fr/item/10940} }
Le, Kim Ngan; McLean, William; Lamichhane, Bishnu. Finite element approximation of a time-fractional diffusion problem for a domain with a re-entrant corner. ANZIAM Journal, Tome 58 (2017) . doi : 10.21914/anziamj.v59i0.10940. http://gdmltest.u-ga.fr/item/10940/