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Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
Turbulence modeling in three-dimensional stenosed arterial bifurcations
1Computational Engineering and Design Group, University of Southampton, Highfield, Southampton SO17 1BJ, UK. jb17@soton.ac.uk
Journal of Biomechanical Engineering
|January 18, 2007
Summary
The transitional k-omega model accurately simulates turbulent blood flow in carotid artery stenosis. This model reveals how mild stenosis increases turbulent viscosity, while severe stenosis causes significant flow recirculation.
Area of Science:
- Fluid dynamics
- Biomedical engineering
- Computational modeling
Background:
- Carotid artery blood flow transitions from laminar to turbulent with stenosis.
- Reynolds-averaged turbulence models are crucial for simulating these complex flows.
- The transitional k-omega model is increasingly favored for hemodynamics.
Purpose of the Study:
- Validate the transitional k-omega model against the RNG k-epsilon model for internal flow.
- Investigate the hemodynamic effects of varying stenosis severity in a carotid artery bifurcation model.
Main Methods:
- Simulated flow through a straight tube to compare transitional k-omega and RNG k-epsilon models without inlet profile assumptions.
- Developed a 3D parametric model of the carotid artery bifurcation.
- Manipulated sinus bulb geometry to create mild, moderate, and severe stenosis conditions.
Main Results:
- Transitional k-omega model showed sensitivity to inflow turbulence variations, unlike RNG k-epsilon.
- Mild stenosis led to higher turbulent viscosity, turbulent kinetic energy, and lower dissipation rates.
- Severe stenosis exhibited increased recirculation, vorticity, helicity, and negative wall shear stress.
Conclusions:
- The transitional k-omega model is suitable for simulating turbulent flow in carotid artery stenosis.
- Stenosis severity significantly impacts hemodynamic parameters like turbulence and flow patterns.
- Parametric modeling allows detailed investigation of local geometry effects on blood flow.
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