We investigated the effect of hemodynamic shear forces on the expression of adhesive molecules, E-selectin, and intercellular adhesion molecule-l (ICAM-1) on human umbilical vein endothelial cells (HUVEC) exposed t o laminar (8 dynes/ cmz) or turbulent shear stress 18.6 dyneslcrn' average), or to a static condition. Laminar flow induced a significant timedependent increase in the surface expres...

Abstract: A detailed numerical study of turbulent flow through a micro-orifice is presented in this work. The flow becomes turbulent due to the orifice at the considered Reynolds numbers (∼104). The obtained flow rates are in good agreement with the experimental measurements. The discharge coefficient and the pressure loss are presented for two input pressures. The laminar stress and the genera...

This paper reports on an experimental study characterizing the laminar-turbulent transition for water flow in circular microtubes. Microtubes with diameters in the range 16.6–32.2 lm of varying length were employed over the Reynolds number range 300–3400. The volume flowrate was measured for an imposed pressure differential using a timed displacement technique. Additionally, the viscous heating...

This review is based on recently published data from our laboratory. We investigated the role of hypertension and laminar flow, hypercholesterolemia and laminar flow and turbulent blood flow/low wall shear stress, and turbulent blood flow/low wall shear stress associated with hypercholesterolemia on aorta remodeling of rats feeding normal diet or hypercholesterolemic diet. Our findings suggest ...

Passive control of hypersonic boundary-layer transition using porous coatings has been studied by theoretical analyses, experiments, and numerical simulations. It was found that porous coating stabilizes Mack’s second mode and destabilizes Mack’s first mode. However, there are only few studies on the stabilization efficiency of porous coating. And no work has been reported about the thermochemi...

We investigated the effect of hemodynamic shear forces on the expression of adhesive molecules, E-selectin, and intercellular adhesion molecule-1 (ICAM-1) on human umbilical vein endothelial cells (HUVEC) exposed to laminar (8 dynes/cm2) or turbulent shear stress (8.6 dynes/cm2 average), or to a static condition. Laminar flow induced a significant time-dependent increase in the surface expressi...

this paper presents the results of numerical simulations of the laminar and turbulent flows inside diverging channels using random vortex methods (rvm). random vortex method is a mesh-free method which solves unsteady vorticity equation instead of solving navier-stokes equations directly to determine the velocity field. in this paper, the velocity potential, which is used as the initial conditi...

In the present work, a theoretical model based on the integral formalism approach for both laminar and turbulent external free convection is extended to Newtonian nanofluids. By using an empirical model for computing nanofluid viscosity, a close attention is focused first on the way the heat transfer is modified by increasing the volume fraction of nanoparticles and then to the transitional thr...

To understand observations of low Reynolds number mixing and flow transitions in viscoelastic fluids, we study numerically the dynamics of the Oldroyd-B viscoelastic fluid model. The fluid is driven by a simple time-independent forcing that, in the absence of viscoelastic stresses, creates a cellular flow with extensional stagnation points. We find that at O(1) Weissenberg number, these flows l...

Bacterial adhesion is a complex process influenced by many factors, including hydrodynamic conditions. They affect the transfer of oxygen, nutrients, and bacterial cells in a water supply and cooling systems. The aim of this study was to identify hydrodynamic effects on bacterial adhesion to and detachment from stainless steel surfaces. For this purpose we observed the behaviour of bacterium L....