Numerical simulation of fully developed sinusoidal and pulsatile (physiological) flow in curved tubes

Abstract

Numerical solutions of the Navier–Stokes equations for fully developed, sinusoidal and pulsatile flows in curved tubes are presented for conditions not accessible to analytical perturbation methods. Simulations of physiological pulsatile flows in the aortic arch reveal a wide variety of interesting flow phenomena, including: (1) complex secondary flows with up to seven vortices in the half-tube; (2) cascaded vortex structures with vortices embedded within vortices; (3) strong secondary flows with associated wall shear stress nearly as large as the axial component; (4) reversal of axial-flow direction at the inside wall; (5) peak axial wall shear stress at the inside wall; (6) highest r.m.s. wall shear stress at the inside wall; and (7) oscillatory impedance, which is accurately described by straight-tube theory.