Vortical flow structure identification and flow transport in arteries.

Our interest in vortices arises for two reasons. Firstly, at moderate to large Reynolds numbers (at least 100) which characterise flow in larger arteries, vortices are quite persistent. The presence of vortices in a flow may exert a strong influence on its behaviour, although tracking vortices may be difficult as they can evolve rapidly. The effects of vortices or vortical structures are particularly evident when considering both flow stability, and the processes of mixing and transport by the flow. The object of this paper is to examine the dynamics both of vortex motion and of particle transport in arteries, and to relate these to parameters such as geometry and unsteadiness. The Lagrangian particle tracking and the vortex dynamic techniques which are described should help in understanding arterial fluid dynamics and suggest new approaches to modelling.