Historically, it has always been understood that the relaxation spectra of linear viscoelastic materials are continuous. Nevertheless, because of their ease of implementation computationally, delta function recovery methods have been and continue to be important, even though they do not generate continuous approximations. Derivative based recovery techniques were popular in the precomputer days...

A dense mixture of granules and liquid often shows a severe shear thickening and is called a dilatant fluid. We construct a fluid dynamics model for the dilatant fluid by introducing a phenomenological state variable for a local state of dispersed particles. With simple assumptions for an equation of the state variable, we demonstrate that the model can describe basic features of the dilatant f...

OBJECTIVE The aim of this study was to analyze how an altered collagen structure affects development of atherosclerotic plaques. METHODS AND RESULTS Fibromodulin-null mice develop an abnormal collagen fibril structure. In apolipoprotein E (ApoE)-null and ApoE/fibromodulin-null mice, a shear stress-modifying carotid artery cast induced formation of atherosclerotic plaques of different phenotyp...

Coronary stents improve resting blood flow and flow reserve in the presence of stenoses, but the impact of these devices on fluid dynamics during profound vasodilation is largely unknown. We tested the hypothesis that stent implantation affects adenosine-induced alterations in coronary hemodynamics and wall shear stress in anesthetized dogs (n = 6) instrumented for measurement of left anterior ...

Time-periodic shear flows can give rise to Parametric Instability (PI), as in the case of the Mathieu equation (Stoker, 1950; Nayfeh and Mook, 1995). This mechanism results from a resonance between the oscillatory basic state and waves that are superimposed on it. Farrell and Ioannou (1996a, b) explain that PI occurs because the snapshots of the velocity profile are subject to transient growth....

A new slit-radial die capable of simultaneously obtaining steady state shear viscosity and the average first normal stress difference coefficient via capillary rheometry has been developed. The are calculated in slit part radial die, respectively. from is compared to viscosities obtained a also magnitude complex oscillatory experiment. value which transient experiment cone-plate geometry molecu...