Turbulence modeling in three-dimensional stenosed arterial bifurcations


Banks, J. and Bressloff, N.W. (2007) Turbulence modeling in three-dimensional stenosed arterial bifurcations Journal of Biomechanical Engineering, 129, (1), pp. 40-50. (doi:10.1115/1.2401182).

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Description/Abstract

Under normal healthy conditions, blood flow in the carotid artery bifurcation is laminar. However, in the presence of a stenosis, the flow can become turbulent at the higher Reynolds numbers during systole. There is growing consensus that the transitional k ? model is the best suited Reynolds averaged turbulence model for such flows. Further confirmation of this opinion is presented here by a comparison with the RNG k? model for the flow through a straight, nonbifurcating tube. Unlike similar validation studies elsewhere, no assumptions are made about the inlet profile since the full length of the experimental tube is simulated. Additionally, variations in the inflow turbulence quantities are shown to have no noticeable affect on downstream turbulence intensity, turbulent viscosity, or velocity in the k? model, whereas the velocity profiles in the transitional k? model show some differences due to large variations in the downstream turbulence quantities. Following this validation study, the transitional k? model is applied in a three-dimensional parametrically defined computer model of the carotid artery bifurcation in which the sinus bulb is manipulated to produce mild, moderate, and severe stenosis. The parametric geometry definition facilitates a powerful means for investigating the effect of local shape variation while keeping the global shape fixed. While turbulence levels are generally low in all cases considered, the mild stenosis model produces higher levels of turbulent viscosity and this is linked to relatively high values of turbulent kinetic energy and low values of the specific dissipation rate. The severe stenosis model displays stronger recirculation in the flow field with higher values of vorticity, helicity, and negative wall shear stress. The mild and moderate stenosis configurations produce similar lower levels of vorticity and helicity. DOI: 10.1115/1.2401182

Item Type: Article
Digital Object Identifier (DOI): doi:10.1115/1.2401182
ISSNs: 0148-0731 (print)
Keywords: turbulence, carotid artery bifurcation, stenosis
Subjects:

ePrint ID: 46209
Date :
Date Event
2007Published
Date Deposited: 01 Jun 2007
Last Modified: 16 Apr 2017 18:36
Further Information:Google Scholar
URI: http://eprints.soton.ac.uk/id/eprint/46209

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