%0 Journal Article %A Ganji, Davood Domiri %A Rafei, M. %A Vaseghi, J. %D 2007 %I Begell House %N 4 %P 361-379 %R 10.1615/HeatTransRes.v38.i4.70 %T Application of Homotopy-Perturbation Method for Systems of Nonlinear Momentum and Heat Transfer Equations %U https://www.dl.begellhouse.com/journals/46784ef93dddff27,47571c91104ca8aa,571508270b2c5605.html %V 38 %X In this paper, we make an attempt to obtain the solutions of systems of nonlinear ordinary and partial differential equations by means of He's homotopy-perturbation method (HPM) which does not require small parameters in the equations. This method is used for solving three types of systems of nonlinear differential equations which are those for laminar mixed convection in a vertical pipe, for a plane Couette flow with variable viscosity, and coupled Burger's equations. To assess the accuracy of the solutions, the results have been compared with the ones of exact solutions. These results reveal that this method is very effective and convenient. It is predicted that the HPM can be found widely applicable in engineering, especially in nonlinear differential systems. %8 2007-06-18