Modeling and Numerical Simulation of Material Science, 2016, 6, 1-9 Published Online January 2016 in SciRes. http://www.scirp.org/journal/mnsms http://dx.doi.org/10.4236/mnsms.2016.61001 How to cite this paper: Rouis, M. and Omrani, K. (2016) On The Numerical Solution of Two Dimensional Model of an Alloy Solidification Problem. Modeling and Numerical Simulation of Material Science, 6, 1-9. http://dx.doi.org/10.4236/mnsms.2016.61001 On The Numerical Solution of Two Dimensional Model of an Alloy Solidification Problem Moeiz Rouis, Khaled Omrani Institut Supérieur des Sciences Appliquées et de Technologie de Sousse, Sousse, Tunisia Received 30 December 2015; accepted 25 January 2016; published 28 January 2016 Copyright © 2016 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/ Abstract In this paper, a linearized three level difference scheme is derived for two-dimensional model of an alloy solidification problem called Sivashinsky equation. Further, it is proved that the scheme is uniquely solvable and convergent with convergence rate of order two in a discrete L -norm. At last, numerical experiments are carried out to support the theoretical claims. Keywords Solidification Problem, Sivashinsky Equation, Linearized Difference Scheme, Solvability, Convergence 1. Introduction In the solidification of a dilute binary alloy, a planer solid-liquid interface is often to be instable, spontaneously assuming a cellular structure. This situation enables one to derive an asymptotic nonlinear equation which di- rectly describes the dynamic of the onset and stabilization of cellular structure ( ) 4 4 2 0, u u u u u t x x x α + + + = (1.1) where α is a positive constant, (see [1] [2]). Equation (1.1) is referred as the Sivashinsky equation. In this article, we introduce the mathematical model for a finite difference discretization to the solution of the periodical boundary of two-dimensional Sivashinsky equation: ( ) ( ) 2 2 , , , 0 , t u u u f u xy t T α +∆ + =∆ < (1.2)