in this study, the dispersion mechanisms of aerosols suspended in a turbulent plane channel flow is investigated using a novel numerical approach. a turbulent channel flow is simulated by a direct numerical simulation (dns) method, for which no-slip boundary conditions are assumed at the top and bottom walls, while periodicity conditions are applied on the other sides. dns, in particular, allow...

Roughness elements or turbulence promoters have been widely used to enhance heat transfer in cooling passages of modern gas turbine blades. Although such ribs substantially enhance heat transfer, the heat transfer coefficient is reduced immediately at corner downstream of each rib, creating hot spots. To remove such hot spots some of the ribs can be detached from the channel walls. In this pape...

The vast biological and industrial applications of laminar flow of viscous fluid through a porous channel with contracting or expanding permeable wall have attest to the importance of studying the flow process. In this paper, two-dimensional flow of viscous fluid in a porous channel through slowly expanding or contracting walls with injection or suction is analyzed using variation parameter met...

this paper presents the results of a numerical study on the heat transfer performance and the removal process of fluid particles under the influence of magnetohydrodynamic mixed convection in a horizontal channel with an open cavity. the bottom wall of the cavity is heated at a constant temperature (th) while the top wall of the channel is maintained at a relatively low temperature (tc). air wi...

In this work, variation of parameter method is applied to study two-dimensional flow of nanofluid in a porous channel through slowly deforming walls with suction or injection. The results of the developed approximate analytical solution using the variation of parameter method is verified with the results of numerical solution using fourth-order Runge-Kutta method coupled with shooing techniques...

The main purpose of this study is to estimate the step heat fluxes applied to the wall of a two-dimensional symmetric channel with turbulent flow. For inverse analysis, conjugate gradient method with adjoint problem is used. In order to calculate the flow field,   two equation model is used. In this study, adjoint problem is developed to conduct an inverse analysis of heat transfer in a channel...

Control of a fluid velocity profile by injection and suction of non-ionized flow in presence of a uniform steady magnetic field has important technical applications. In this paper, the unsteady incompressible and viscous conducting fluid flow has been investigated in a circular channel. The channel wall has been assumed to be non-conducting and porous. It has been subjected to a uniform steady ...

In this study, the least square method is applied to study the laminar flow, heat transfer and microrotation of MgO-Ag/water micropolar hybrid nanofluid in a permeable channel. The bottom wall is hot and coolant fluid is injected into the channel from the top wall. The base fluid in the channel is water and volume fraction of nanoparticle (50% Ag and 50% MgO by volume) is between 0 and 0.02. By...

This paper presents the results of a numerical study on the heat transfer performance and the removal process of fluid particles under the influence of magnetohydrodynamic mixed convection in a horizontal channel with an open cavity. The bottom wall of the cavity is heated at a constant temperature (Th) while the top wall of the channel is maintained at a relatively low temperature (Tc). Air wi...

A numerical model is developed to simulate the transport phenomena in the flow channel between parallel plates with porous and non-porous (or impermeable) walls. The continuity and momentum equations were solved first, assuming the wall Reynolds number in the range of with the suction or injection of air at a speed equal to the uniform inlet velocity. The results show that at constant inlet and...