血液时变剪切力模拟装置的研究  

Development of a new simulation device of blood time-varying shear force

作　　者：符珉瑞 高斌[1] 常宇 刘有军[1] FU Minrui;GAO Bin;CHANG Yu;LIU Youjun(Faculty of Environment and Life,Beijing University of Technology,Beijing 100124;National Clinical Research Center for Child Health,The Children’s HospitalZhejiang University School of Medicine,Hangzhou 310003)

机构地区：[1]北京工业大学环境与生命学部,北京100124 [2]浙江大学医学院附属儿童医院,国家儿童健康与疾病研究中心,杭州310003

出　　处：《北京生物医学工程》2024年第5期464-470,共7页Beijing Biomedical Engineering

摘　　要：目的开发一种Couette型血液时变剪切力模拟装置,为研究流动诱导的血液损伤提供实验平台。方法血液剪切装置主要由三个部分组成,分别是驱动控制模块、剪切流产生模块和暴露时间控制模块。其中,最核心的部分是剪切流产生模块,其原型为轴流式血泵,经过重新设计后改为轴流式Couette装置(溶血泵)。溶血泵转子和外壳间存在间隙,用以产生流动诱导的剪切力。溶血泵整体采用医用钛合金制作,前后导叶内使用红宝石滑动轴承。通过注射泵的流量控制暴露时间,采用伺服电机结合同步带传动结构驱动溶血泵转子旋转。利用计算流体力学(computational fluid dynamics,CFD)数值模拟软件Fluent对溶血泵内部流场进行模拟。对血液剪切装置的响应速度和稳定性进行实验验证,并做溶血实验。结果CFD结果表明,在微小间隙内可以产生一个均匀的高剪切力区域,而其他地方的剪切力较低。由于采用伺服电机驱动,装置最高可以产生300 Pa、25 Hz的时变剪切力。设备在相同条件下进行多次实验时,实验结果的变异系数小于10%。通过调整溶血泵转速和血流速度,在暴露时间(1 s和2 s)和剪切力(50、100、150、200、250 Pa)的矩阵下,采用来自不同个体的血液对剪切诱导产生的溶血进行量化,在相同实验条件下个体之间的差异是影响实验结果的关键因素。结论血液时变剪切力模拟装置能够满足相关实验要求,在实验过程中需要重点关注由于血液自身差异对实验结果的影响。Objective To develop a Couette type blood time-varying shear force simulator,and to provide an experimental platform for studying flow-induced blood injury.Methods The blood shear device is mainly composed of three parts,which are drive control module,shear flow generation module and exposure time control module.Among them,the most central part is the shear flow generation module,which is originally designed as an axial flow blood pump and redesigned as an axial flow Couette device(hemolytic pump).There is a gap between the hemolytic pump rotor and the housing to generate flow-induced shear forces.The hemolytic pump is made of medical titanium alloy as a whole,and ruby sliding bearings are used in the front and rear guide blades.The exposure time is controlled by the flow rate and volume of the injection pump,and the rotation of the hemolytic pump rotor is driven by the servo motor combined with the synchronous belt transmission structure.The computational fluid dynamics(CFD)numerical simulation software Fluent is used to simulate the internal flow field of the hemolysis pump.The response speed and stability of the blood shear device are verified by experiments,and the hemolysis experiment is carried out.Results CFD results show that a uniform region of high shear forces can be generated within a small gap,while the shear forces are lower elsewhere.Due to the use of servo motor drive,the device can produce up to 300 Pa,25 Hz time-varying shear force.The variation coefficient of the experimental results is less than 10%when the equipment is tested several times under the same conditions.By adjusting the hemolysis pump speed and blood flow velocity,blood from different individuals is used to quantify the shear-induced hemolysis under the matrix of exposure time(1,2 s)and shear force(50,100,150,200,250 Pa).The difference between individuals is the key factor affecting the experimental results under the same experimental conditions.Conclusions The blood time-varying shear stress simulation device can meet the relevan

关 键 词：血流动力学 血液剪切装置 剪切力 暴露时间 溶血 

分 类 号：R318.04[医药卫生—生物医学工程]