[01] Sina Pasha Zanous, Department of Mechanical Engineering, Babol Noushirvani University of Technology, Babol, Iran. [02] Rouzbeh Shafaghat, Department of Mechanical Engineering, Babol Noushirvani University of Technology, Babol, Iran. [03] Qadir Esmaeili, Department of Mechanical Engineering, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran.

Blood flow through a stenosis artery may have different flow characteristics and produce different forces acting on the plaque surface and artery wall. The present study investigates the flow through the 55% (by area reduction) stenosed artery, both numerically and experimentally. First, the experimental study is carried out on a rigid asymmetric model of a stenosed artery. Afterward the flows are numerically simulated for the same flow rates, geometry, and fluid properties and to make sure the numerical results are reliable, the experimental and numerical pressure drop are compared. Finally, an ideal symmetric stenosed artery with same stenosed severely is numerically studied and the results of two numerical simulations are compared. The governing differential equations of blood flow are discretized using finite-volume method in the generalized body-fitted coordinates. In addition, an elliptic method for nearly orthogonal grid generation is presented in numerical study. The aim of this study is isolate the effect of actual stenosed geometry on the flow characteristics such as, wall shear stress (WSS), length of separation regions, swirl flow and maximum velocity distribution at different Reynolds numbers by comparing with ideal symmetric stenosis. It is pointed out that these probabilities are much higher for asymmetric model than symmetric one. Based on our results, high and oscillatory WSS values play a significant role in the destruction of endothelium. Furthermore, it is shown that WSS exceeds the critically reported value, 420 dyne/cm2, only at asymmetric model in maximum flow rate, that causes damage to the endothelium cell layer

Arterial Disease, Post-Stenotic, Computational Domains, Newtonian, General Curvilinear Coordinate, Wall Shear Stress

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