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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]

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]

In a previous paper (Pantokratoras and Magyari, 2009), the Electro-Magnetohydro dynamic (EMHD) free convection flow of a weakly conducting fluid from an electromagnetic actuator was considered. In the present note, we study the cases where the Riga-plate either moves with constant velocity (Sakiadis flow) or the Riga-plate is situated in a constant free stream (Blasius flow). The results are obtained with the numerical simulation of the governing equations. Velocity profiles are presented, as well as values of the skin friction. Results are presented for both impermeable and permeable Riga-plate with uniform suction or uniform injection. [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]

The work of Mahmood and Merkin (ZAMP 39:186–203, 1988) concerns the mixed convection flow along a stationary cylinder in a constant free stream. In the present note, we extend the above work to general situations involving a moving cylinder. [ABSTRACT FROM AUTHOR]

Abstract: The flow of a laminar wall plume in a constant transverse magnetic field is considered. The results are obtained with the numerical solution of the governing equations and cover both small and large ξ values and Prandtl numbers from 0.01 to 100. The similar wall plume has been investigated in the past but the nonsimilar has not been treated until now and it is solved here for the first time. [Copyright &y& Elsevier]

A theoretical study of the effect of variable viscosity and variable thermal conductivity on the classical plane Couette-Poiseuille flow is presented in this brief communication. The investigation concerns engine oil, air, and water taking into account the variation of these quantities with temperature. The results are obtained with the numerical simulation of the governing equations and cover large temperature differences. Velocity and temperature profiles are presented as well as the volume flow rate and the heat flux between the plates. It is found that temperature profiles are close to the straight line for oil and water and depart significantly from the straight line for air due to nonlinear thermal conductivity. Dynamic viscosity plays an important role on the results which depart significantly from those of a fluid with constant properties. [ABSTRACT FROM AUTHOR]

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

A letter to the editor is presented in response to the article "Similarity Analysis in Magnetohydrodynamics: Hall Effects on Forced Convective Heat and Mass Transfer of Non-Newtonian Power Law Fluids Past a Semi-Infinite Vertical Flat Plate," by A.A. Afify, E.M. Aboeldahab and E.S. Mohamed.

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

The present comment concerns some doubtful results included in the above papers. [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 article presents mathematical expressions such as momentum equation, continuity equation and energy equation related to a research which analyzes the effect of thermal buoyancy and internal heat generation along a stationary vertical plate in a uniform free stream. It informs that the mathematical expressions are based on the fluid kinematic viscosity, the fluid specific heat and the fluid thermal expansion coefficient.

In this paper, we study the steady laminar flow in a fluid-saturated porous medium channel bounded by two parallel plates with constant but unequal temperatures. One plate is moving with constant velocity while the other is stationary. For the porous medium, the Brinkman--Darcy--Forchheimer model is used. The investigation concerns engine oil, water, and air, taking into account the variation of their physical properties with temperature. The results are obtained with the direct numerical solution of the governing equations and cover large temperature differences. It is found that dynamic viscosity plays an important role on the results, which depart significantly from those of a fluid with constant properties when the temperature difference between the plates is large. Except that there are cases where the flow is restricted near the moving plate while at the lower part of the channel, the fluid is motionless. [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]

A theoretical study of the effect of a constant transverse magnetic field on the boundary layer flow over a flat plate is presented in this note. The free stream velocity decreases along the plate according to laws of Howarth, Tani and Gortler. The results are obtained with the direct numerical solution of the governing equations with primitive variables. The application of the magnetic field moves the separation point farther downstream in comparison with the flow without a magnetic field. [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]