A New Implicit Finite Difference Method for Solving Time Fractional Diffusion Equation

Abstract

In this paper, a time fractional diffusion equation on a finite domain is con-<br /> sidered. The time fractional diffusion equation is obtained from the standard<br /> diffusion equation by replacing the first order time derivative by a fractional<br /> derivative of order 0 < a< 1 (in the Riemann-Liovill or Caputo sence). In<br /> equation that we consider the time fractional derivative is in the Caputo sense.<br /> We propose a new finite difference method for solving time fractional diffu-<br /> sion equation. In our method firstly, we transform the Caputo derivative into<br /> Riemann-Liovill derivative. The stability and convergence of this method are<br /> investigated by a Fourier analysis. We show that this method is uncondition-<br /> ally stable and convergent with the convergence order O( 2+h2), where t and<br /> h are time and space steps respectively. Finally, a numerical example is given<br /> that confirms our theoretical analysis and the behavior of error is examined<br /> to verify the order of convergence.