Comment on: The three-dimensional flow past a stretching sheet and the homotopy perturbation method, by P.D. Ariel, Computers and Mathematics with Applications 54 (2007) 920925
In his application of the homotopy perturbation (HP) method to the problem of the three-dimensional flow past a stretching sheet, P.D. Ariel [The three-dimensional flow past a stretching sheet and the homotopy perturbation method, Comput. Math. Appl. 54 (2007) 920925] encountered secular terms in the second order approximation, which he could not avoid. It is shown here that these secular terms can be removed by coordinate straining. Moreover, the form of an HP solution, which is free from secular terms at all levels of approximation, and which can be determined recursively, is indicated.
homotopy perturbation method secular terms coordinate straining uniformly valid solution