Numerical predictions of blood flow patterns and hemodynamic stresses in Abdominal Aortic Aneurysms (AAAs) are performed in a two-aneurysm, axisymmetric, rigid wall model using the spectral element method. Physiologically realistic aortic blood flow is simulated under pulsatile conditions for the range of time-averaged Reynolds numbers corresponding to a range of peak Reynolds numbers The vortex dynamics induced by pulsatile flow in AAAs is characterized by a sequence of five different flow phases in one period of the flow cycle. Hemodynamic disturbance is evaluated for a modified set of indicator functions, which include wall pressure wall shear stress and Wall Shear Stress Gradient (WSSG). At peak flow, the highest shear stress and WSSG levels are obtained downstream of both aneurysms, in a pattern similar to that of steady flow. Maximum values of wall shear stresses and wall shear stress gradients obtained at peak flow are evaluated as a function of the time-average Reynolds number resulting in a fourth order polynomial correlation. A comparison between predictions for steady and pulsatile flow is presented, illustrating the importance of considering time-dependent flow for the evaluation of hemodynamic indicators.
Blood Flow in Abdominal Aortic Aneurysms: Pulsatile Flow Hemodynamics
Contributed by the Bioengineering Division for publication in the JOURNAL OF BIOMECHANICAL ENGINEERING. Manuscript received by the Bioengineering Division September 30, 1999; revised manuscript received May 15, 2001. Associate Editor: C. R. Ethier.
Finol, E. A., and Amon, C. H. (May 15, 2001). "Blood Flow in Abdominal Aortic Aneurysms: Pulsatile Flow Hemodynamics ." ASME. J Biomech Eng. October 2001; 123(5): 474–484. https://doi.org/10.1115/1.1395573
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