Document Type : Full Research Paper


1 M.Sc Graduate, Biomechanics Group, Department of Mechanical Engineering , Sahand University of Technology

2 Assistant Professor, Biomechanics Group, Department of Mechanical Engineering , Sahand University of Technology

3 Professor, Biomechanics Group, Department of Mechanical Engineering , Sahand University of Technology



Biomechanics believe that, the arteries are remodeled under the influence of hemodynamic and mechanical factors. Biomechanical factors such as Opening Angle and the Tethering could have important effects on this phenomenon. The effects of various Opening Angle and Tethering during thoracic aorta aging on arterial wall stress have been studied. ADINA software is used for numerical simulation.In this study, for the first time, numerical methods of Fluid-Structure Interaction have been used to study and simulate effects of Opening Angle and the Tethering in elastic artery remodeling due to age. Large deformation theory has been used for modeling changes of arterial radius; furthermore, behavior of Newtonian fluid has been used for blood. Pulsatile pressure and physiological Pulsatile flow waveforms have been applied to simulate transient behavior of arterial system. The results show that opening angle has further effect on circumferential stress so smooth distribution of circumferential stress on the wall accrued. Also, increasing Opening Angle with age reverses the circumferential stress distribution slop across the arterial wall. Tethering has further effect on axial stress. Decreasing Tethering in remodeling process over age leads to increase stress levels in the aged artery. Also, arterial wall shear stress in remodeled artery shows significant reduction in maximum, mean and amplitude values that caused reduction of pathological effects of endothelial cells.  


Main Subjects

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