应用欧拉-拉格朗日方法分析动脉粥样硬化性颈动脉血流的流-固相互作用  

Fluid-solid interaction analysis of blood flow in the atherosclerotic carotid artery using the Eulerian-Lagrangian approach

作　　者：Majid SIAVASHI Ava BINA Mojtaba SAYADNEJAD Borhan BEIGZADEH Majid SIAVASHI;Ava BINA;Mojtaba SAYADNEJAD;Borhan BEIGZADEH(Applied Multi-Phase Fluid Dynamics Lab.,School of Mechanical Engineering,Iran University of Science and Technology,Tehran,Iran;Biomechatronics and Cognitive Engineering Research Lab.,School of Mechanical Engineering,Iran University of Science and Technology,Tehran,Iran)

机构地区：[1]Applied Multi-Phase Fluid Dynamics Lab.,School of Mechanical Engineering,Iran University of Science and Technology,Tehran,Iran [2]Biomechatronics and Cognitive Engineering Research Lab.,School of Mechanical Engineering,Iran University of Science and Technology,Tehran,Iran

出　　处：《Journal of Central South University》2024年第1期151-168,共18页中南大学学报（英文版）

摘　　要：本研究旨在模拟不同狭窄程度和脉搏率的颈动脉搏动血流。采用流-固耦合(FSI)和任意拉格朗日-欧拉(ALE)方法研究了不同狭窄程度、脉搏率和动脉壁性质对周围流体的影响。分别应用Carreau-Yasuda非牛顿超弹性模型和修正Mooney-Rivin超弹性模型于具有非牛顿行为的血液和超弹性血管壁。结果得到血液的壁面径向位移、压力分布、轴向速度分布和壁面剪切应力。通过增加狭窄的严重程度,轴向速度、血压变化、最大壁面剪切应力和壁面径向位移均呈增长趋势。当脉率在狭窄程度为75%时,最大流量矩、壁面径向位移、压力、轴向速度和壁面剪应力的最大值均增大。此外,与弹性和刚性模型相比,将动脉壁视为超弹性模型,将其周围流体视为非牛顿和非定常,可以使模拟更加真实。在严重程度高达50%的狭窄中,红细胞受到轻微损害,而在严重程度为75%的狭窄中观察到溶血。通过改善动脉粥样硬化,弹性模量从500 k Pa提高到2 MPa,在60 bpm脉率和狭窄程度75%下,剪切应力最大值增长65%。与刚性和弹性动脉壁相比,动脉壁的超弹性模型导致较低的轴向速度、较低的血压、较低的剪切应力和较高的径向位移。This study aims to simulate pulsatile blood flow in the carotid artery with different stenosis severities and pulse rates.The effects of different severities of stenosis,pulse rates,and arterial wall properties on the surrounding fluid are investigated by using fluid-structure interaction(FSI) and arbitrary Lagrangian-Eulerian(ALE) methods.CarreauYasuda non-Newtonian and modified Mooney-Rivin hyperelastic models are applied for blood with non-Newtonian behavior and hyperelastic blood vessel' s wall,respectively.Results are presented in terms of wall radial displacement,pressure distribution,the axial velocity profile,and wall shear stress for blood.By increasing the stenosis severities,there would be a change in several parameters.Axial velocity,variation of blood pressure,the maximum wall shear stress,and wall radial displacement experience a growth.Furthermore,when the pulse rate grows in the stenosis severity of 75%,the maximum flow rate moments,maximum values for wall radial displacement,pressure,axial velocity,and wall shear stress increase as well.Using a hyperelastic model for the arterial wall,as opposed to elastic and rigid models,and treating the surrounding fluid as non-Newtonian and unsteady,allows us to achieve a more realistic simulation.In the stenosis having up to 50% of severity,red blood cells are under the enforcement of insignificant damage,while hemolysis is observed in the severe stenosis of 75%.By improving atherosclerosis,which leads to the development of elastic modulus from 500 k Pa to 2 MPa,the 65% growth of the maximum value of shear stress at 60 bpm pulse rate and in the stenosis with 75% severity has been noticed.It can be demonstrated that hyperelastic models of the arterial walls lead to lower axial velocity,lower blood pressure,lower shear stress,and higher radial displacement,as opposed to rigid and elastic arterial walls.

关 键 词：流-固耦合 狭窄严重程度 脉率变化 超弹性的动脉 动脉粥样硬化 

分 类 号：R543.4[医药卫生—心血管疾病]