## HKBU Staff Publication

Journal Article

#### Department/Unit

Department of Mathematics

English

#### Abstract

In this paper, we study the Crank--Nicolson alternative direction implicit (ADI) method for two-dimensional Riesz space-fractional diffusion equations with nonseparable coefficients. Existing ADI methods are only shown to be unconditional stable when coefficients are some special separable functions. The main contribution of this paper is to show under mild assumptions the unconditional stability of the proposed Crank--Nicolson ADI method in discrete $\ell^2$ norm and the consistency of cross perturbation terms arising from the Crank--Nicolson ADI method. Also, we demonstrate that several consistent spatial discretization schemes satisfy the required assumptions. Numerical results are presented to examine the accuracy and the efficiency of the proposed ADI methods.

#### Keywords

nonseparable variable coefficients, Crank–Nicolson ADI methods, space-fractional diffusion equations, unconditional stability analysis

10-2019

#### Source Publication Title

Journal of Scientific Computing

81

1

375

391

Springer

#### DOI

10.1007/s10915-019-01020-2

https://doi.org/10.1007/s10915-019-01020-2

08857474

15737691

COinS