Received Mar 10, 2016 Revised May 12, 2016 Accepted May 24, 2016 This study focuses on the behavior of blood flow through diseased artery in the presence of porous effects. The laminar, incompressible, fully developed, non-Newtonian in an artery having axially non-symmetric but radially symmetric stenosis is numerically studied. Here blood is represented as Herschel-Bulkley fluid model and flow...

BACKGROUND Intimal hyperplastic thickening (IHT) is a frequent cause of prosthetic bypass graft failure. Induction and progression of IHT is thought to involve a number of mechanisms related to variation in the flow field, injury and the prosthetic nature of the conduit. This study was designed to examine the relative contribution of wall shear stress and injury to the induction of IHT at defin...

The deformation of red blood cells in microvessels was investigated numerically for various vessel diameters, hematocrits, and shear rates. We simulated blood flow in circular channels with diameters ranging from 9 to 50 μm, hematocrits from 20% to 45%, and shear rates from 20 to 150 s(-1) using a particle-based model with parallel computing. The apparent viscosity predicted by the simulation w...

Background. Compliance mismatch is a negative factor and it needs to be considered in arterial bypass grafting. Objective. A computational model was employed to investigate the effects of arterial compliance mismatch on blood flow, wall stress, and deformation. Methods. The unsteady blood flow was assumed to be laminar, Newtonian, viscous, and incompressible. The vessel wall was assumed to be l...

Blood flow throughout the vascular circuit exerts a tangential force called shear stress upon all vessel walls. Under homeostatic conditions, shear stress is maintained within a narrow range. It has been shown that an alteration from this normal range of shear stress activates a biochemical signaling cascade in a process termed mechanotransduction. Although the signaling mechanism has not been ...

In this paper, the Al2O3-water nanofluid flow in laminar and turbulent flows inside tubes fitted with diamond-shaped turbulators is numerically modeled. The nanofluid flow is modeled by employing a two-phase mixture method and applying the constant heat flux boundary condition at tube walls. In the results, the effects of different parameters such as the geometry of turbulators, volume fraction...

Atherosclerotic disease, and the subsequent complications of thrombosis and plaque rupture, has been associated with local shear stress. In the diseased carotid artery, local variations in shear stress are induced by various geometrical features of the stenotic plaque. Greater stenosis severity, plaque eccentricity (symmetry) and plaque ulceration have been associated with increased risk of cer...

While it is universally accepted that plankton continually experience a dynamic fluid environment, their sensitivity to the features of the surrounding flow field at the relevant length and time scales of the organism is poorly characterized. The present study uses bioluminescence as a tool to understand how the red tide dinoflagellate Lingulodinium polyedrum (5 Gonyaulax polyedra) responds to ...

Recent investigations indicate that the initial event in the pathogenesis of atherosclerosis involves an (auto)immunologic injury to the vessel wall. Heat shock proteins (hsps), which are expressed on the endothelial cell surface, constitute possible autoantigens. After being exposed to shear stress of 30 dyne/cm(2) in vitro by means of a rotational viscometer, human umbilical vein endothelial ...

The complexity of the skewed 3-D boundary layer (figure 3) necessitates the use of multiple coordinate systems. The Tunnel coordinate system is right-handed with the x-axis parallel to the tunnel centerline pointing downstream and the y-axis perpendicular to the tunnel floor pointing up. The Wall-Shear-Stress coordinate system is right-handed with the x-axis in the shear-stress direction at the...