Effect of Wall Elasticity on Pulsatile Flow in Aortic Bifurcation : Flow Visualization Study in Bifurcation Models

Abstract

To understand the effect of wall elasticity on pulsatile blood flow, the structure of physiological pulsatile flow was studied in a rigid and elastic aortic bifurcation models by means of a flow visualization technique. In both models, flow separation was observed at the lateral wall of bifurcation during the accelerated and decelerated flow periods ; secondary flow existed inside the flow separation. Although flow in the rigid model was strongly disturbed during the decelerated and back-flow periods, flow disturbances were minor in the elastic model. The scale of the flow separation zone was larger in the elastic model than in the rigid model. According to these results, wall elasticity reduces flow disturbances in aortic bifurcation, and possibly affects wall shear stress which is an important factor in atherogenesis.