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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]

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

The flow induced by a sphere rotating inside an incompressible, non-Newtonian, power law fluid has been investigated numerically. The rotating sphere is enclosed in a concentric cubic box with solid boundaries. The fluid power-law index varied between 0.2 and 2 thereby covering both shear-thinning and shear-thickening fluids and the Reynolds number varied between 0.01 and 10,000. Numerical predictions show significant differences between shear-thinning and shear-thickening fluids. In the first case the flow is confined near the sphere whereas in the second case the flow extends up to the box plates. In creeping flow and shear-thinning fluids the torque is independent of the Reynolds number. [ABSTRACT FROM AUTHOR]

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

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

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

The present comment concerns some doubtful mathematical calculation that produced misleading results which are presented in the above paper. [ABSTRACT FROM AUTHOR]

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

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

A serious error exists in the above paper. [ABSTRACT FROM AUTHOR]

Lamella gravity settlers are often used in water treatment to make sedimentation tanks more cost-effective. Effective surface area for settlement is increased by the inclined plates giving such systems a smaller footprint than the conventional tanks. In this paper a numerical model was used to simulate the dynamics and flow structure of a rectangular sedimentation tank for potable water through a multiphase approach, using computational fluid dynamic (CFD) methods. Two configurations have been examined, one with a system of inclined parallel plates (lamellar settlers) and another with a conventional design, in order to evaluate the influence of lamellar settlers in the process efficiency. Unlike most of the previous numerical investigations which studied the lamellar settlers separately, the present numerical approach studies the whole sedimentation tank with a full scale system of inclined parallel plates. The momentum exchange between the primary and the secondary phase (particles) is taken into account, using a Lagrangian method (discrete phase model) with two-way coupled calculations. Contours of stream function, velocity and concentration are presented, as well as the velocity and concentration profiles for the inclined plates. The results show that the lamellar settlers influence the flow field and increase the sedimentation efficiency by 20% in comparison with the convectional design. [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]

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]