Numerical Analysis of Physiological Flow in a Curved Tube. Model of an Aortic Arch Flow.

We measured the velocity profiles of pulsatile entrance flow in a strongly curved tube using a laser-Doppler anemometer in order to simulate blood flow in the aortic arch under various conditions, i.e., a ratio of tube to curvature radius of 1/3, Womersley parameters of 12 and 18, and peak Dean number up to 1200. Axial isovelocity contours of the cross-section showed the potential vortex to be near the entrance, and with the maximum velocity there being skewed towards the inner wall; thereafter shifting towards the outer wall. During the deceleration phase, reverse axial flow occurred near the inner wall, and a region of this flow extended downstream. The large curvature contributes to the enhancement of the secondary flow and flow reversal, which elevates the wall-shear stress oscillations. The location of elevated wall-shear oscillations corresponds to the vessel wall region where atherosclerotic formation frequently occurs; thereby indicating that both the large curvature and pulsatility play key roles in formation of localized atherosclerotic lesions.

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Dean vortices in curved tube flow: 5. 3-D MRI and numerical analysis of the velocity field

AIChE Journal ◽

10.1002/aic.690391003 ◽

1993 ◽

Vol 39 (10) ◽

pp. 1592-1602 ◽

Cited By ~ 30

Author(s):

Kun Yong Chung ◽

Georges Belfort ◽

William A. Edelstein ◽

Xianming Li

Keyword(s):

Numerical Analysis ◽

Velocity Field ◽

Tube Flow ◽

Dean Vortices ◽

Curved Tube ◽

Curved Tube Flow

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1008 Numerical analysis of flow in an aortic arch model

The Proceedings of Conference of Kansai Branch ◽

10.1299/jsmekansai.2005.80._10-15_ ◽

2005 ◽

Vol 2005.80 (0) ◽

pp. _10-15_-_10-16_

Author(s):

Hisanobu OKADA ◽

Kiyoshi BANDO ◽

Tsutomu TAJIKAWA ◽

Kenkichi OHBA ◽

Atsushi SAKURAI

Keyword(s):

Numerical Analysis ◽

Aortic Arch ◽

Arch Model

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Entry Flow in a Circular Tube of Aortic Arch Dimensions

Journal of Biomechanical Engineering ◽

10.1115/1.3138504 ◽

1984 ◽

Vol 106 (4) ◽

pp. 351-356

Author(s):

K. O. Lim ◽

J. S. Kennedy ◽

C. M. Rodkiewicz

Keyword(s):

Boundary Layer ◽

Reynolds Number ◽

Secondary Flow ◽

Flow Pattern ◽

Aortic Arch ◽

Steady Flow ◽

Circular Tube ◽

Boundary Layer Separation ◽

Curved Tube ◽

Separation Zones

Steady flow within a uniform circular curved tube formed by two 90-deg elbows was studied as a function of ψ, the angle between the planes of curvature of the two elbows. Boundary layer separation was found at two locations. The sites of these separation zones were observed to be essentially independent of ψ while the Reynolds number at which separation was first detected was found to decrease as ψ increased. The relation between separation and the pathogenesis of atherosclerosis is discussed. Secondary flow pattern was found to depend on ψ and in some instances on Reynolds number as well.

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