Direct numerical simulation (DNS) is used to study the effect of individual (hemispherical) and distributed roughness on supersonic flat plate boundary layers. In both cases, roughness generates a shear layer and counter–rotating pairs of unsteady streamwise vortices. The vortices perturb the shear layer, resulting in trains of hairpin vortices and a highly unsteady flow. Mach 3.37 flow past a ...

The purpose of this investigation was to study the effect of the presence of red blood cells (RBCs) in the plasma layer near the arteriole wall on nitric oxide (NO) and oxygen (O2) transport. To this end, we extended a coupled NO and O2 diffusion-reaction model in the arteriole, developed by our group, to include the effect of the presence of RBCs in the plasma layer and the effect of convectio...

in the present study, vibration of cylindrical laminates with different layers and angles were studied. in order to actuate and polarize in radial direction, a piezoelectric layer was located at outer surface of composite shell. laminates were assumed long enough so that plane strain state analysis in 2d can be used properly. in order to satisfy the boundary conditions, variables in terms of fo...

A new Boussinesq-type model describing periodic wave propagation over a constant depth has been developed for the cases where the effects of a turbulent boundary layer are significant. In this paper, the eddy viscosity model is employed in the turbulent boundary layer and is further approximated as a linear function of the distance measured from the seafloor. The boundary-layer velocities are c...

A resistance-in-series model is used to describe the pervaporation performance of elastomeric membranes in the removal of volatile organic components from water. Equations have been derived to describe the organic component flux as a function of feed concentration, permeability of the organic component in the membrane, membrane thickness and liquid boundary layer mass transfer coefficient. The ...

The free conv ection boundary layer flow of a Darcy-Brinkman fluid that is induced by a constant-temperature horizontal semi-infinite surface embedded in a fluid-saturated porous medium is inv estigated in this work. It is shown that both the Darcy and Rayleigh numbers may be scaled out of the boundary layer equations, leav ing a parabolic system of equations with no parameters to vary. The equ...

The performance of acoustic treatments installed on aircraft engines is strongly influenced by the boundary layer of the grazing flow on the surface of the liner. The parametric study presented in this paper illustrates the extent of this effect and identifies when it is significant. The acoustic modes of a circular duct with flow are calculated using a finite sound fields found in current turb...

‎The problem of two-phase MHD boundary layer flow, heat and mass transfer over a stretching sheet with fluid-particle suspension and thermal radiation has been studied. The effect of mass transfer in dusty fluid over a stretching sheet is considered for the first time. The governing equations are reduced to a set of non-linear ordinary differential equations under suitable similarity transforma...

The technique used to control the airflow is based on the electro-hydrodynamic actuator which is also called plasma actuator. This actuator ensures the airflow control thanks to the electric wind created by the electrical corona discharge. This ionic wind is developed at the profile surface tangential to the initial free airflow so that it has a significant effect on the boundary layer flow. Th...