Numerical and experimental study of the 3D flow in a graft-artery junction model

Vascular graft occlusion after implantation is one of the most urgent problems of vascular surgery. This paper presents results of numerical simulation and ultrasound/strain gauge measurements of the 3D pulsating flow of blood-mimicking fluid in a model of the junction of the graft with superficial femoral artery. The calculations have pointed, in particular, at occurrence of an extensive stagnant zone with low wall shear stresses near the graft-artery junction, which can accelerate the graft occlusion. Both the simulation and the ultrasound measurements have shown that a four-vortex flow structure forms just after the graft-artery junction zone, which transforms into a two-vortex flow structure further downstream. Numerical and experimental data on the pressure drop at the graft-artery junction model were in a good accordance.