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Some errors exist in the above paper. [ABSTRACT FROM AUTHOR]

In the above paper, there are some typographical errors and some serious errors. [ABSTRACT FROM AUTHOR]

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

Some errors exist in the above paper. [ABSTRACT FROM AUTHOR]

In a recent paper by Makinde the effect of thermal buoyancy along a moving vertical plate with internal heat generation was considered. The plate thermal boundary condition was a convective condition with a heat transfer coefficient proportional to x-1/2. The fluid thermal expansion coefficient was proportional to x-1, and the internal heat generation was assumed to decay exponentially across the boundary layer and proportional to x-1 in order that the problem accepts a similarity solution. In the present work, the same problem without heat generation is considered, with constant heat transfer coefficient and constant thermal expansion coefficient which is more realistic and has much more practical applications. The present problem is non-similar and results are obtained with the direct numerical solution of the governing equations. The problem is governed by the Prandtl number, the non-dimensional distance along the plate and a convective Grashof number, which is introduced for the first time. It is found that the wall shear stress, the wall heat transfer, and the wall temperature all increase with increasing distance and the wall temperature tends to one. The influence of the convective Grashof number is to increase the wall shear stress and the wall heat transfer and to reduce the wall temperature. [ABSTRACT FROM AUTHOR]

Some suspicious equations and scientific inaccuracies of the aforementioned paper are concerned in this comment. [ABSTRACT FROM AUTHOR]

The present note presents some errors in the aforementioned paper published in Mathematical Methods in the Applied Sciences. Two errors are found in the definition of the non-dimensional parameters and correct results are presented for temperature profiles included in figure 10 of the previous paper. [ABSTRACT FROM AUTHOR]

Computational fluid dynamics (CFD) methods are employed to evaluate the influence of temperature variations on the flow field in an actual sedimentation tank for potable-water treatment. A series of experimental measurements of temperature variation has been conducted in that sedimentation tank. The mixed-convection problem caused by the density variations and the horizontal stream is considered at low temperatures (0-10°C) where the variation of water density is strongly nonlinear. Three cases have been examined: (1) one in the ascending, (2) one in the descending parabolic density region, and (3) one in the linear density region. The thermophysical properties of water have been incorporated into the CFD code. All simulations have been conducted for a transient, turbulent flow field. The momentum exchange between the primary and the secondary phase (particles) is considered. The results show that in the parabolic density region, only a few particles are trapped in the bottom, whereas many of them float near the surface and escape from the tank causing a low-tank efficiency. The opposite happens in the linear-density region where the tank efficiency is much better. [ABSTRACT FROM AUTHOR]

The two basic equations in the mentioned article are wrong. [ABSTRACT FROM AUTHOR]

The steady laminar natural convection along a vertical isothermal plate with linear or non-linear Rosseland radiation is investigated in this paper. The problem is self-similar and the results are obtained with the direct numerical solution of the governing equations. This problem is governed by the Prandtl number, the temperature parameter as well as the radiation parameter, and the influence of these parameters on the results are presented in tables and figures. A new radiation parameter is introduced which leads to an asymptotic state. It is found that the temperature profiles take a special S-shape form with an inflection point. Moreover, it is shown that when the wall shear stress increases the wall heat transfer decreases and vice versa. [ABSTRACT FROM AUTHOR]

The flow of a fluid past a flat plate of finite length and infinite width (two-dimensional flow) is considered. The plate is heated by convection from a fluid with constant temperature T with a constant heat transfer coefficient h. In all previous works, the problem was considered using boundary layer theory whereas, in the present work, the solution is based on the full Navier-Stokes equations. The problem is investigated numerically with a finite volume method using the commercial code ANSYS FLUENT. The governing parameters are the Reynolds number, the new heat transfer parameter, and the Prandtl number. In addition, the influence of these three parameters on the temperature field is investigated. It is found that high Reynolds and high Prandtl numbers the wall temperature increases along the plate. They reach a maximum near the trailing edge then decrease. The same occurs as the heat transfer parameter increases. When the Reynolds and Prandtl numbers are low, the plate temperature tends to become symmetric, with a maximum at the middle of the plate. The temperature profiles become thicker as the Reynolds number and the Prandtl number is reduced while the temperature profiles become thicker as the heat transfer parameter increases. [ABSTRACT FROM AUTHOR]

Abstract: The steady laminar boundary layer flow along a vertical stationary plate with convective surface boundary condition is investigated in this paper. The heat transfer coefficient is considered either constant or variable along the plate and the problem is either non-similar or similar. The results are obtained with the direct numerical solution of the governing equations. The problem is governed by Prandtl number and a convective parameter and the influence of these parameters on the results are presented in tables and figures. There are differences in the results between the non-similar and similar case at low values of the convective parameter but as this parameter increases the differences decrease and the flow tends to the classical natural convection along a vertical isothermal plate. [Copyright &y& Elsevier]

Abstract: The steady laminar boundary layer flow over a perforated plate, in the presence of suction, moving in a parallel stream with constant velocity is investigated in this paper. The temperature boundary condition on the plate is a convective condition. In contrast to the majority of the previous works, in the present paper the heat transfer coefficient and the suction velocity are constant and the problem is non-similar. The results are obtained with the direct numerical solution of the governing equations. The problem is governed by Prandtl number, the Biot number, the velocity ratio parameter and a streamwise parameter and the influence of these parameters on the results are presented in tables and figures. It was found that the temperature reaches an asymptotic state and an analytical solution has been found for the calculation of wall temperature at the asymptotic state. [Copyright &y& Elsevier]

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]

Abstract: The flow of a laminar wall jet along a horizontal plate is considered. The plate is porous and fluid can be either injected or sucked through it. The plate is isothermal and its temperature is different from that of the ambient fluid. The results are obtained with the numerical solution of the governing equations. For the case of uniform injection new results have been found although this problem has been investigated in the past. Among them is that the dimensionless wall shear stress and the dimensionless wall heat transfer become zero at for . For the case of uniform suction all the results are new and are presented for the first time in the literature. Among them is the disappearance of the jet at a universal distance from the jet exit (). [Copyright &y& Elsevier]

Abstract The present comment concerns some doubtful results included in the above paper. [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 comment concerns a paper published in Chemical Engineering Science Journal. • The problem is non-similar. However the authors treated the problem as similar. • In non-similar problems one x-dependent parameter is used. The authors used three. [ABSTRACT FROM AUTHOR]

Two mistakes exist in [1]. [ABSTRACT FROM AUTHOR]

This discussion concerns some doubtful results included in this paper. [ABSTRACT FROM AUTHOR]

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

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

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

This communication concerns some doubtful results included in the above paper. [ABSTRACT FROM AUTHOR]

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

The present comment concerns some doubtful results in the above paper. [ABSTRACT FROM AUTHOR]

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

This communication concerns some doubtful results included in a recent comment by N. Freidoonimehr and A.B. Rahimi, Journal of Molecular Liquids 216 (2016) 99–102. [ABSTRACT FROM AUTHOR]

We study the steady laminar flow along an isothermal vertical impermeable and permeable plate embedded in a saturated porous medium for which the Darcy law is valid. The investigation concerns air and water taking into account the variation of their physical properties with temperature in both upward and downward flow. The results are obtained with the direct numerical solution of the governing equations and cover relatively large temperature differences. The Prandtl number varied between 0.54 and 0.86 for air and between 3.83 and 13.18 for water. It is found that the variation of physical properties with temperature play an important role on wall heat transfer and wall shear stress and large departures from the constant properties values are observed. The largest differences of wall heat transfer and wall shear stress from the corresponding constant properties values reach 75% and 357% in air and 42% and 388% in water. [ABSTRACT FROM AUTHOR]