Temporal and spatial wall shear stress characterization at the renal artery branching site

The time-dependent flow in the vicinity of an arterial branch is considered. The geometries are derived from patients with renal artery stenosis. The details of the flow from the abdominal aorta into the renal artery are considered by well resolved numerical simulations. The flow was compared between arteries with stenosis and the same arteries after the stenosis was removed. In the presence of a stenosis close to the branching site, the flow in the aorta downstream the branching artery, is reversed and generated time-dependent vertical structures near the wall. These structures lead to a strong time- and space-varying wall shear stress with peak values at the opening of the artery. The flow into the branching renal artery exhibited also a swirling motion which in turns results in spiraling flow in the renal artery.