A Numerical Study on the Hemodynamic and Shear Stress of Double Aneurysm Through S-Shaped Vessel

Abstract

Abdominal aortic aneurysm (AAA) is a degenerative disease de¯ned as the abnormal ballooning of the abdominal aorta (AA) wall which is usually caused by atherosclerosis. The aneurysm grows larger and eventually ruptures if it is not diagnosed and treated. Aneurysms occur mostly in the aorta, the main artery of the chest and abdomen. The aorta carries blood°ow from the heart to all parts of the body, including the vital organs, the legs, and feet. The objective of the present study is to investigate the combined e®ects of aneurysm and curvature on°ow characteristics in S-shaped bends with sweep angle of 90 at Reynolds number of 900. The°uid mechanics of blood°ow in a curved artery with abnormal aortic is studied through a mathematical analysis and employing Cosmos°ow simulation. Blood is modeled as an incompressible non-Newtonian°uid and the°ow is assumed to be steady and laminar. Hemodynamic characteristics are analyzed. Grid independence is tested on three successively re¯ned meshes. It is observed that the abrupt expansion induced by AAA results in an immensely disturbed regime. The results may have implications not only for understanding the mechanical behavior of the blood°ow inside an aneurysm artery but also for investigating the mechanical behavior of the blood°ow in di®erent arterial diseases, such as atherosclerosis.

Measurement of the mechanical properties of the handball, volleyball, and basketball using DIC method: a combination of experimental, constitutive, and viscoelastic models

“…The weight and outer diameter of the balls were precisely measured using a high resolution scale 0.0001 gr ± 0.1 % (Shimadzu Electronics Balances, Kyoto, Japan) and a digimatic ruler having a resolution of 0.005 mm ± 0.05 % (Insize, Vienna, Austria) [19][20][21]. The outer diameters of the handball, volleyball, basketball balls were 7.40 ± 0.25, 20.90 ± 0.50, and 23.80 ± 0.80 cm, respectively.…”

A computational fluid–structure interaction model to predict the biomechanical properties of the artificial functionally graded aorta

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A computational fluid–structure interaction model of the blood flow in the healthy and varicose saphenous vein

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