Numerical simulation of steady flow fields in a model of abdominal aorta with its peripheral branches.

In the present study, a numerical calculation procedure based on a finite volume method was developed to simulate steady flow fields in a model of abdominal aorta with its peripheral branches. The study focused on the steady baseline flow fields and the wall shear stress (WSS) distribution as well as the localization of the reversed flow regions and results were compared to those obtained by other investigators. In the case of resting conditions, the existence of a region of reversed flow of about one to two diameters in size and next to the renal arteries and along the posterior wall as observed by other researchers was confirmed. However, under the exercise conditions this region could be wiped out. The flow reversal along the lateral walls proximal to the bifurcation persisted in both rest and exercise conditions. The WSS distribution and the wall shear stress gradient distribution were obtained. The lowest WSS occurred near the ostia of the renal arteries and the lateral walls of the iliac arteries. And the highest is always at the turn to the branch. The results were generally consistent with those obtained experimentally and numerically by other investigators. It was also shown that the steady flow might be used to depict the averaged behavior of pulsatile flow. The present computer code provides a platform for the future more realistic simulations.