Numerical solutions of diffusion-controlled moving boundary problems which conserve solute

Numerical methods of finding transient solutions to diffusion problems in two distinct phases that are separated by a moving boundary are reviewed and compared. A new scheme is developed, based on the Landau transformation. Finite difference equations are derived in such a way as to ensure that solute is conserved. It is applicable to binary alloys in planar, cylindrical, or spherical geometries. The efficiency of algorithms which implement the scheme is considered. Computational experiments indicate that the algorithms presented here are of first order accuracy in both time and space. (c) 2005 Elsevier Inc. All rights reserved.