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The document discusses the dimensional and dimensionless momentum equations presented in a paper by Nawaz et al. The equations describe fluid flows in boundary layers. The document highlights the differences between the dimensional equation and the dimensionless equations, particularly in terms of the time derivative. It points out that the fractional parameter is absent in the dimensional equation, suggesting that the two terms are not compatible. The given text discusses the compatibility between the dimensional and dimensionless equations for fluid flow. It also identifies errors in equations presented in a study by Nawaz et al., including terms with different units and incorrect values of alpha. The authors of the study declare no conflicts of interest. [Extracted from the article]

The aim of this comment is to point out three major errors in the paper Akolade et al. (2024). [ABSTRACT FROM AUTHOR]

Hundreds of papers are published each year in the field of boundary layer flow. However, in many papers serious errors appear. In the present paper an attempt has been made to summarize these errors. Unlabelled Image • Error concerning truncation of profiles • Error concerning contradiction between pdf and transformed ode • Error using the local similarity method in non-similar problems • Error using dimensional parameters instead of non-dimensional parameters [ABSTRACT FROM AUTHOR]

The flow of a non-Newtonian, power-law conducting fluid under the effect of a constant transverse magnetic field is considered. The flow is produced by a plate moving with constant velocity in a calm fluid. The plate is porous and fluid can either be sucked or injected through it. The boundary layer equations are transformed into a nondimensional form and are solved with a finite difference method. Part of this problem has been investigated in the past but only for suction and pseudo-plastic fluids. However, all flows of the present work reach an asymptotic state and exact analytical solutions exist for Newtonian fluids. In the present work we extend the investigation to both pseudo-plastic Newtonian and dilatant fluids in both suction and injection cases. [ABSTRACT FROM AUTHOR]

The Blasius and Sakiadis flows of a non-Newtonian power-law conducting fluid under the effect of a constant transverse magnetic field is considered. The boundary layer equations are transformed into a non-dimensional form and a new dimensionless magnetic parameter is introduced. The transformed boundary layer equations are solved with a finite difference method. Both Blasius and Sakiadis flows reach an asymptotic state and become one-dimensional with the increase of the coordinate in the streamwise direction. The flow behavior in the intermediate region is studied and exact analytical solutions have been found for the asymptotic state. The characteristics of physical and engineering interest are discussed in the paper in detail. [ABSTRACT FROM AUTHOR]

The Blasius and Sakiadis flows of a non-Newtonian power-law fluid are considered. The plate is porous and fluid can be either injected or sucked through it. The boundary layer equations are transformed into a nondimensional form and are solved with a finite difference method. For the case of uniform suction, new results have been found, although this problem has been investigated in the past. Among them are analytical solutions for dilatant fluids of the Blasius flow and analytical solutions of the Sakiadis flow for all values of the power-law index. For the case of uniform injection, the characteristics of the flow until a separation state are investigated and discussed. [ABSTRACT FROM AUTHOR]

Abstract: The flow of a laminar wall jet along either a moving plate, or in a free stream, or in combined moving plate and free stream is considered. The plate is isothermal and its temperature is different from that of the ambient fluid. The governing boundary-layer equations are converted into non-dimensional form and are solved numerically. Velocity and temperature profiles as well as the variation of wall shear stress and wall heat transfer are presented for all cases considered. For the case of a moving plate new results have been found although this problem has been investigated in the past. For the case of the free stream and the combined moving plate/free stream all the results are new and are presented for the first time in the literature. The three cases have been tackled with a unified way. [ABSTRACT FROM AUTHOR]

The steady forced convection flow of a power-law fluid over a horizontal plate embedded in a saturated Darcy-Brinkman porous medium is considered. The flow is driven by a constant pressure gradient. In addition to the convective inertia, also the “porous Forchheimer inertia” effects are taken into account. The pertinent boundary value problem is investigated analytically, as well as numerically by a finite difference method. It is found that far away from the leading edge, the velocity boundary layer always approaches an asymptotic state with identically vanishing transverse component. This holds for pseudoplastic (0 < n < 1), Newtonian ( n = 1), and dilatant ( n > 1) fluids as well. The asymptotic solution is given for several particular values of the power-law index n in an exact analytical form. The main flow characteristics of physical and engineering interest are discussed in the paper in some detail. [ABSTRACT FROM AUTHOR]

Abstract: In the latter years the title problem has been examined in a large number of research papers. The present Note emphasizes, however, that the effect of thermal radiation in the linearized Rosseland approximation is quite trivial, both physically and computationally. Namely, it always reduces to a simple rescaling of the Prandtl number by a factor involving the radiation parameter. This implies that a comprehensive study of the Prandtl-number dependence without thermal radiation effects represents per se a detailed study of the radiation effects, too. In other words, the solution of the radiation problem for optically thick media in the linearized Rosseland approximation does not require any additional numerical or analytical effort compared to the same problem without radiation, making in this respect dozens of papers superfluous. [Copyright &y& Elsevier]

The present discussion concerns some doubtful results included in the discussed paper. [ABSTRACT FROM AUTHOR]

A theoretical study of the effect of a constant transverse magnetic field on the boundary layer flow over a vertical isothermal plate is presented in this note. The results are obtained with the direct numerical solution of the governing equations with primitive variables. The results cover both small and large ξ values, Prandtl numbers from 0.01 to 10 are the first complete accurate results for the classical MHD free convection flow along a vertical isothermal plate. [ABSTRACT FROM AUTHOR]

A theoretical study of the effect of uniform suction on the classical Blasius and Sakiadis flow is presented in this note. The results are obtained with the numerical simulation of the governing equations. Except of the numerical solution of the boundary layer equations we produced some simple analytical solutions for the asymptotic suction state. Velocity and temperature profiles are presented for different values of the suction parameter ξ. It is found that the velocity asymptotic state is reached at ξc≈2 for all cases, that is, Blasius flow, Sakiadis flow and combined Blasius-Sakiadis flow. However, for the temperature asymptotic state no universal suction parameter exists and ξc depends on the Prandtl number. [ABSTRACT FROM AUTHOR]