Coronary artery bypass graft (CABG) operation for coronary artery disease with different types of grafts has a large clinical application world wide. Immediately after this operation patients are usually relieved of their chest pain and have improved cardiac function. However, after a while, these bypass grafts may fail due to for example, neointimal hyperplasia or thrombosis. One of the causes...

We experimentally investigate the mechanical behaviour in cyclic shear of a granular material near a solid wall in a pressure controlled annular shear cell. The use of a model system (glass beads and sawtooth shaped solid surface) enables the study of the influence of the wall roughness. After an initial shakedown procedure ensuring reproducible results in subsequent tests, wall shear stress S,...

Cross correlations of the fluctuating wall-shear stress and the streamwise velocity in the logarithmic region of turbulent boundary layers are reported over 3 orders of magnitude change in Reynolds number. These results are obtained using hot-film and hot-wire anemometry in a wind tunnel facility, and sonic anemometers and a purpose-built wall-shear stress sensor in the near-neutral atmospheric...

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 ...

A three-dimensional computer model of human aortic arch with three branches is reproduced to study the pulsatile blood flow with Finite Element Method. In specific, the focus is on variation of wall shear stress, which plays an important role in the localization and development of atherosclerotic plaques. Pulsatile pressure pulse is used as boundary condition to avoid flow entry development, an...

BACKGROUND AND PURPOSE Saccular intracranial aneurysm is a common disease that may cause devastating intracranial hemorrhage. Hemodynamics, wall remodeling, and wall inflammation have been associated with saccular intracranial aneurysm rupture. We investigated how saccular intracranial aneurysm hemodynamics is associated with wall remodeling and inflammation of the saccular intracranial aneurys...

In this paper, nonlinear behavior of strengthened steel plate shear walls (SPSWs) by FRP laminates theoretically and numerically has been investigated. In the first part, a new method, “the composite-plate frame Interaction (C-PFI) method”, has been introduced to predict the shear behavior of the composite steel plate shear wall systems (CSPSWs). In the second part, several models of one-story ...

Particle image velocimetry (PIV) has been gaining acceptance as a routine tool to evaluate the flow fields associated with fluid mechanical devices. We have developed algorithms to investigate the wall shear-rates within the 50cc Penn State artificial heart using low magnification, conventional particle image velocimetry (PIV). Wall shear has been implicated in clot formation, a major post-impl...

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...

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...