Karami Fatemeh, Hossainpour Siamak, Ghalichi Farzan
Department of Mechanical Engineering, Sahand University of Technology, Sahand New Town, East Azarbayjan, Tabriz, Iran. E-mails:
Biomed Mater Eng. 2018;29(1):95-108. doi: 10.3233/BME-171715.
Accumulation of cholesterol and other atherogenic lipids such as low-density lipoprotein (LDL) in artery wall causes reduction of vessel diameter and artery stenosis. The study of the mass transfer of these large molecules in the wall with considering effective factors on lumen flow and different physiological factors is the subject considered nowadays. In this paper, results of two dimensional and axi-symmetric simulations of three different models of the artery with 60% stenosis under pulsatile blood flow are presented. Filtration velocity of LDL mass transport in the permeable artery wall and shear stress of blood flow are investigated using ADINA software Three different flow models are considered. In the first and second models, the filtration velocity considered as a given parameter and constant in arterial wall boundary, while in third model arterial wall considered as porous wall, the filtration velocity is calculated from pressure difference as an input parameter of the model. The results show that filtration velocity is strongly depend on geometry and it is not constant along the wall, contrary to simplified models. The results of concentration variations in lumen and wall illustrate the increase in near wall LDL concentration or concentration polarization.
胆固醇和其他致动脉粥样硬化脂质（如低密度脂蛋白（LDL））在动脉壁中的积累会导致血管直径减小和动脉狭窄。考虑到管腔血流的影响因素和不同生理因素，研究这些大分子在血管壁中的传质是当前研究的课题。本文给出了在脉动血流作用下，三种不同程度（60%狭窄）动脉模型的二维和轴对称模拟结果。使用ADINA软件研究了可渗透动脉壁中LDL物质传输的过滤速度和血流的剪切应力。考虑了三种不同的流动模型。在第一种和第二种模型中，过滤速度被视为给定参数并在动脉壁边界处保持恒定，而在第三种模型中，动脉壁被视为多孔壁，过滤速度根据压差计算得出，作为模型的输入参数。结果表明，与简化模型相反，过滤速度强烈依赖于几何形状，并且沿壁面并非恒定不变。管腔和血管壁中浓度变化的结果表明，近壁LDL浓度增加或浓度极化现象。
