Flow dynamics and wall shear-stress variation in a fusiform aneurysm
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Pulsatile flow through a tube featuring a sinusoidal bulge is computed in order to determine the flow dynamics and wall shear-stress conditions encountered under conditions representative of blood flow through a human abdominal aortic aneurysm. A high-order spectral-element algorithm is employed to accurately determine velocity and vorticity fields, plus wall shear stresses, which are notoriously difficult to measure experimentally. A greater level of detail in the flow is revealed when compared to recent particle image velocimetry experiments. For both the mean and standard deviation of wall shear stress, minimum levels are found at the widest point of the aneurysm bulge, and maximum levels are recorded in the distal (downstream) region of the bulge. In an aneurysm with length and maximum diameter 2.9 and 1.9 times the artery diameter, respectively, peak instantaneous wall shear stress is 2.4 times greater than the peak wall shear stress recorded in a healthy vessel.
KeywordsAneurysm Blood flow Computational fluid dynamics Direct numerical simulation Spectral-element method Wall shear stress
Wall shear stress
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- 4.Kondo S, Hashimoto N, Kikuchi H, Hazama F, Nagata I, Kataoka H (1997) Cerebral aneurysms arising at nonbranching sites. An experimental study. Stroke 28(2): 398–403Google Scholar
- 7.Fry DL (1968) Acute vascular endothelial changes associated with increased blood velocity gradients. Circ Res 22: 165–197Google Scholar
- 9.Ku DN, Giddens DP, Zarins CK, Glagov S (1985) Pulsatile flow and atherosclerosis in the human carotid bifurcation. Positive correlation between plaque location and low oscillating shear stress. Arterioscler Thromb Vasc Biol 5: 293–302Google Scholar
- 11.Kataoka K, Taneda M, Asai T, Kinoshita A, Ito M, Kuroda R (1999) Structural fragility and inflammatory response of ruptured cerebral aneurysms. A comparative study between ruptured and unruptured cerebral aneurysms. Stroke 30(7): 1396–1401Google Scholar
- 21.Womersley JR (1955) Method for the calculation of velocity, rate of flow and viscous drag in arteries when the pressure gradient is known. J Physiol 127: 553–563Google Scholar
- 22.Maier SE, Meier D, Boesinger P, Moser UT, Vieli A (1989) Human abdominal aorta: comparative measurements of blood flow with MR imaging and multigated doppler US. Radiology 171(2): 487–492Google Scholar
- 27.Hoshina K, Sho E, Sho M, Nakahashi TK, Dalman RL (2003) Wall shear stress and strain modulate experimental aneurysm cellularity. J Vasc Surg 37(5): 1067–1074Google Scholar