Vortex structure and strength of secondary flows in model aortic arches

A numerical method is developed to study the flow structures in the aortic arch. The method solves the incompressible Navier–Stokes equations. It uses a third‐order upwind scheme for the convective terms and the second‐order central scheme for the viscous terms. A DDADI time integration is used for achieving fast convergence. For the unsteady solutions, the second‐order Crank–Nicolson method coupled with the diagonalized diagonal dominated alternating direction implicit scheme (DDADI) time integration are used. The numerical results show that the method is about 2.5‐order accuracy in space and 1.8‐order accuracy in time. Then the method is used to investigate the vortex structure and strength of secondary flows in the aortic arch. Four different arch geometries are constructed to see the effect of arch configuration. Many flow properties such as pressure drop, vortex strength and separation are computed and compared among the four arch models. Copyright © 2002 John Wiley & Sons, Ltd.