LES OF NON-NEWTONIAN PHYSIOLOGICAL BLOOD FLOW (original) (raw)

Abstract

Large Eddy Simulation (LES) is performed to study the physiological pulsatile transition to turbulent non-Newtonian blood flow through a 3D model of arterial stenosis using the different non-Newtonian blood viscosity models. The computational domain has been chosen is a simple channel with a biological type stenosis formed eccentrically on the top wall. The physiological pulsation is generated at the inlet of the model using the fourth harmonic of the Fourier series of the physiological pressure pulse (Womersley [1]). The computational results are presented in terms of the post-stenotic re-circulation zone, shear stress, mean and turbulent kinetic energy.

Key takeaways

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  1. Large Eddy Simulation (LES) reveals critical insights into non-Newtonian blood flow in arterial stenosis.
  2. The study employs a 3D channel model with 50% cross-sectional area reduction at y/L = 0.0.
  3. Non-Newtonian models show an increased post-stenotic re-circulation zone, raising thrombosis risk.
  4. The maximum shear stress drop at the upper wall is -0.07730 for the Power-law model, 32% higher than Newtonian.
  5. Turbulent kinetic energy peaks differ significantly; non-Newtonian models show delayed transition compared to Newtonian.

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References (12)

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