We study the rheology of cornstarch suspensions, a non – Brownian particle system that exhibits discontinuous shear thickening. Using Magnetic Resonance Imaging (MRI), the local properties of the flow are obtained by the determination of local velocity profiles and concentrations in a Couette cell. For low rotational rates, we observe shear localization characteristic of yield stress fluids. Wh...

Hemodynamic shear stress, the frictional force acting on vascular endothelial cells, is crucial for endothelial homeostasis under normal physiological conditions. When discussing blood flow effects on various forms of endothelial (dys)function, one considers two flow patterns: steady laminar flow and disturbed flow because endothelial cells respond differently to these flow types both in vivo a...

Blood vessels alter their morphology and function in response to changes in blood flow, and their responses are based on blood flow detection by the vascular endothelium. Endothelial cells (ECs) covering the inner surface of blood vessels sense shear stress generated by flowing blood and transmit the signal into the interior of the cell, which evokes a cellular response. The EC response to shea...

The influence of shear on the lamellar phase of a semi-dilute solution (36il (w /w) of tetra ethylenglycol dodecylether (CH3[CH2]11 [OCH2CH2]40H, C12E4) in water was investigated by Small Angle Light Scattering (SALS), Small Angle Neutron Scattering (SANS) and rheology. A plateau modulus was determined by low amplitude oscillatory shear experiments. A strong scattering peak perpendicular to the...

Fluid velocities were measured by laser Doppler velocimetry under conditions of pulsatile flow in a scale model of the human carotid bifurcation. Flow velocity and wall shear stress at five axial and four circumferential positions were compared with intimal plaque thickness at corresponding locations in carotid bifurcations obtained from cadavers. Velocities and wall shear stresses during diast...

BACKGROUND In vivo studies have demonstrated that reasonable exercise training can improve endothelial function. To confirm the key role of wall shear stress induced by exercise on endothelial cells, and to understand how wall shear stress affects the structure and the function of endothelial cells, it is crucial to design and fabricate an in vitro multi-component parallel-plate flow chamber sy...

The shear rheology of dense colloidal and granular suspensions is strongly nonlinear, as these materials exhibit shear-thinning and shear-thickening, depending on multiple physical parameters. We numerically study the rheology of a simple model of soft repulsive particles at large densities, and show that nonlinear flow curves reminiscent of experiments on real suspensions can be obtained. By u...

Abstract Special features of magnetohydrodynamic waves linear dynamics in smooth shear flows are studied. Quantitative asymptotic and numerical analysis are performed for wide range of system parameters when basic flow has constant shear of velocity and uniform magnetic field is parallel to the basic flow. The special features consist of magnetohydrodynamic wave mutual transformation and over-r...

Flow and transport are studied in transparent model fractures with rough complementary self-affine walls with a relative shear displacement ~u. The aperture field is shown to display long range correlations perpendicular to ~u: for flow in that direction, the width and geometry of the front of a dyed shear-thinning polymer solution displacing a transparent one have been studied as a function of...

Fluid flow has been shown to be a potent physical stimulus in the regulation of bone cell metabolism. In addition to membrane shear stress, loading-induced fluid flow will enhance chemotransport due to convection or mass transport thereby affecting the biochemical environment surrounding the cell. This study investigated the role of oscillating fluid flow induced shear stress and chemotransport...