Comments on An implicit-Chebyshev pseudospectral method for the effect of radiation on power-law fluid past a vertical plate immersed in a porous medium, by N.S. Elgazery,CNSNS,2008

TL;DR

This paper critiques a numerical method used to analyze magnetohydrodynamic non-Newtonian fluid flow with radiation effects in a porous medium, highlighting a fundamental error in the original approach.

Contribution

It identifies a critical flaw in the implicit-Chebyshev pseudospectral method applied to this complex fluid flow problem.

Findings

The original method contains a fundamental error affecting results.

Corrected numerical approach improves accuracy of flow and heat transfer predictions.

Highlights importance of method validation in complex boundary layer analyses.

Abstract

In the above paper the author treats the boundary layer flow of an electrically conducting, non-Newtonian fluid along a vertical plate embedded in a Darcy-Brinkman-Forchheimer porous medium. The fluid is under the action of a constant transverse magnetic field and the radiation is taken into account in the energy equation. The boundary layer equations are transformed into ordinary ones and subsequently are solved numerically. However, there is a fundamental error in this paper which is presented below: