# An analytical approximate method for solving unsteady state two-dimensional convection-diffusion equations

## Authors

• A. S. J. Al-Saif College of Education for Pure Science; Basrsh University
• Zinah A. Hasan College of Education for pure sciences, Basrah University

## Keywords:

convergence, accuracy, RK-4, NATM, HPM, RDTM, convection-diffusion, unsteady

## Abstract

In this paper, an analytic approximate method for solving the unsteady two-dimensional convection-diffusion equations is introduced. Also, the convergence of the approximate methods is analyzed. Three test examples are presented, two have exact and one has not exacted solutions. The results obtained show that these methods are powerful mathematical tools for solving linear and nonlinear partial differential equations, moreover, new analytic Taylor method (NATM), reduced differential transform method (RDTM), and homotopy perturbation method (HPM), are more accurate and have less CPU time than the other methods.

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2022-06-22

## How to Cite

Al-Saif, A. S. J. ., & Hasan, Z. A. (2022). An analytical approximate method for solving unsteady state two-dimensional convection-diffusion equations. JOURNAL OF ADVANCES IN MATHEMATICS, 21, 73–88. https://doi.org/10.24297/jam.v21i.9242

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