@Article{NMTMA-12-3, author = {}, title = {Finite Difference Schemes for the Variable Coefficients Single and Multi-Term Time-Fractional Diffusion Equations with Non-Smooth Solutions on Graded and Uniform Meshes}, journal = {Numerical Mathematics: Theory, Methods and Applications}, year = {2019}, volume = {12}, number = {3}, pages = {845--866}, abstract = {

Finite difference scheme for the variable coefficients subdiffusion equations with non-smooth solutions is constructed and analyzed. The spatial derivative is discretized on a uniform mesh, and $L$1 approximation is used for the discretization of the fractional time derivative on a possibly graded mesh. Stability of the proposed scheme is given using the discrete energy method. The numerical scheme is $\mathcal{O}$ ($N$−min{2−$α$,$rα$}) accurate in time, where $α$ (0 < $α$ < 1) is the order of the fractional time derivative, $r$ is an index of the mesh partition, and it is second order accurate in space. Extension to multi-term time-fractional problems with nonhomogeneous boundary conditions is also discussed, with the stability and error estimate proved both in the discrete $l$2-norm and the $l$-norm on the nonuniform temporal mesh. Numerical results are given for both the two-dimensional single and multi-term time-fractional equations.

}, issn = {2079-7338}, doi = {https://doi.org/10.4208/nmtma.OA-2018-0046}, url = {https://global-sci.com/article/90421/finite-difference-schemes-for-the-variable-coefficients-single-and-multi-term-time-fractional-diffusion-equations-with-non-smooth-solutions-on-graded-and-uniform-meshes} }