短期辅助用直流电磁驱动搏动式血泵设计与测试

设计一种直流电磁驱动搏动式血泵并测试样机性能指标。首先,提出一种通过直流螺线管使永磁体进行往复直线运动的驱动方法,并通过螺线管内部磁场的数值模拟设计内部磁场趋于匀强磁场的补偿螺线管结构,结合两者设计直流电磁驱动搏动式血泵。然后,通过制作样机并搭建加速度实验台,测量接入不同直流电流时血泵样机可提供的磁力驱动力,并验证通电螺线管发热问题。最后,搭建流量实验台,在前、后负荷范围分别为5~30和50~80 mmHg的情况下,测量血泵样机的流量性能指标。血泵样机提供的磁力驱动力与电流呈正相关线性关系,并且在接入2.7 A的电流时,其数值大小即可满足驱动要求;在接入的直流电流为2.7 A且血泵驱动频率为80 次·min^-1时,一方面通电螺线管与血液接触的内表面温度上升1 ℃后平稳在27 ℃,另一方面除了前、后负荷压差达到70 mmHg及以上,血泵样机流量均大于3.0 L·min^-1。该直流电磁驱动血泵满足离体器官灌注和体外循环短期辅助的临床要求,且对体外循环血泵的发展具有重要意义。     

磁悬浮式带辅助支点离心血泵的可行性研究

提出带一个辅助支点的磁悬浮内置电机式离心血泵，泵出口采用了全新的设计方法，泵进出口及叶轮在一条轴线上，使血泵的流体结构较为合理。陶瓷滚珠支承使泵运行更稳定，可承受更大的负荷，且陶瓷在血液中不会被腐蚀，和血液相容性较好。在此基础上对血泵性能进行了测试，初步实验表明该泵的性能良好，其物理特性能满足临床体外循环及辅助循环的需要。     

小型离心血泵的最佳化设计:泵体设计及血泵性能

我们为体外循环研制了一种小型化的离心血泵、它由一台微型的直流伺服马达直接驱动。通过体外实验,发现当叶轮的叶片与人口成20°角、与出口成50°角时,最有利于泵血容量和降低溶血。本研究项中,评价了螺旋线状泵体对血泵功能的影响,以确定最佳的泵体形状。与非螺旋线泵体的泵相     

一种轴流血泵的磁液双悬浮支承系统

【摘 要】 目的:为解决第三代血泵中磁力和液力悬浮系统体积偏大、发热多、水力性能差、血损严重等问题,提出一种磁液双悬浮支承系统。 方法:磁液双悬浮支承系统轴向靠磁力、径向靠径向液力共同实现转子的稳定悬浮;分别利用ANSYS电磁模块和楔形动压承载原理对轴向磁力、径向液力进行分析,利用Fluent对磁液双悬轴流血泵的水力性能进行仿真分析。 结果:对悬浮系统轴向、径向承载力的分析以及悬浮实验结果表明该系统可以实现稳定的悬浮;Fluent仿真及水力实验表明当血泵转子转速为9 500 r/min以上时,能满足人体需要。 结论:磁液双悬浮支承系统具有较好的悬浮性、水力性能,可作为第三代血泵进一步改进的选择方向。     

一种植入式磁悬浮离心血泵的体外流体力学实验研究

通过体外模拟循环实验台对一种植入式磁悬浮离心血泵进行体外流体力学实验.以新鲜羊血为循环介质,通过体外循环台测定在后负荷为100 mmHg,血泵在不同转速下的输出量；通过控制血泵的转速,测定在固定泵速下不同后负荷下的输出量.血泵测试工作电压为24V,电流波动于0.3～0.75 A.血泵功率为7.2～18W.在后负荷为10...     

基于电磁驱动的体外膜肺氧合搏动式泵血系统

根据电磁学原理建立梯度线圈-永磁体模型,本研究设计了一款新型电磁驱动搏动式血泵,主要包括驱动装置、泵头装置、冷却系统以及体外循环管路等.搏动式血泵运动速率接近正常人体心率,模仿心脏的节律跳动,产生搏动式血流,实现了搏动式泵血.通过搭建实验平台,采集基于电磁驱动的体外膜肺氧合(extracorporeal membran...     

基于快速溶血预估模型的离心血泵叶轮特性数值分析

离心血泵叶轮形态是决定其内部流场剪切应力致血液细胞损伤的重要因素之一。对具有不同叶轮形态的离心血泵进行流体动力分析及数值溶血预估有助于提高血泵的综合性能。本文采用低雷诺数修正SSTκ-ω湍流模型,对四种不同叶轮形态的离心血泵内部流场进行计算,包括压力场、速度场以及剪切应力场分布等;并运用快速溶血预估模型计算各血泵的标准溶血参数值(NIH)。分析结果表明,虽然四种血泵的压力场分布均符合要求,但对数螺旋线叶轮血泵流道中的涡流和回流得到了明显改善,高剪切应力区域体积只占总体积的0.004%,NIH为0.0089,对血液细胞破坏最小。     

磁偶合驱动轴流式血泵的可行性研究

报道一种新的自行设计研制的磁偶合驱动轴流式血泵 ,电机采用自制的中空无刷直流电机 ,血泵进出口及叶轮在一条轴线上 ,使血泵内与流体力学有关的结构更为合理 ,对血泵性能进行了测试和验证 ,实验表明该泵的性能良好 ,其流体力学特性能满足临床体外循环及辅助循环的需要     

基于自整定模糊PI算法的磁耦合离心血泵控制研究

本文研究和设计了磁耦合离心血泵的控制系统,简要介绍了磁耦合离心血泵的结构和原理,分析了人体体循环模型。血泵性能的优劣不仅和结构材料有关,控制算法也对其有很大的影响。针对无刷直流电机,研究了电机电流双闭环控制算法;为了在不同的工作状态下算法能够自适应参数的变化,采用了自整定模糊PI控制算法,给出了模糊规则的设计方法。利用Matlab Simulink组件仿真电机控制系统检验算法的性能,并简要介绍了算法在硬件系统上的实现方法。最后搭建硬件平台进行实验,证明了自整定模糊PI控制算法能大大改善血泵的动态和稳态性能,实现了电机转速和血泵流量的稳定和可调。     

磁耦合驱动搏动式血泵的可行性研究

目的提出一种磁耦合驱动搏动式血泵结构并验证其可行性。方法基于磁场传递往复作用力模型以及推拉互挽式结构设计磁耦合驱动搏动血泵,通过建立磁力驱动模型,计算耦合力大小,制作样机并对样机进行体外循环模拟试验,获得压力和流量实验数据。结果采用生理盐水作为循环介质,固定后负荷,增加前负荷,血泵输出量减少,没有明显线性趋势;固定前负荷,增加后负荷,血泵输出量减少,且具有一定线性趋势。设置驱动频率为75次/min时,调节前、后负荷改变范围分别为0.665~3.990 k Pa(5~30 mm Hg)和5.320~11.970 k Pa(5~30 mm Hg),可使输出量在保证线性关系条件下达到2.0~3.1 L/min。结论该搏动式血泵流体力学特性基本满足体外膜肺循环的需要,仍需进一步研究和改进;研究结果具有重要的应用前景,尤其对替代目前临床体外膜肺氧合设备的血泵装置具有重要意义。     

A new design for a compact centrifugal blood pump with a magnetically levitated rotor

A compact centrifugal blood pump has been developed using a radial magnetic bearing with a two-degree of freedom active control. The proposed magnetic bearing exhibits high stiffness, even in passively controlled directions, and low power consumption because a permanent magnet, incorporated with the rotor, suspends its weight. The rotor is driven by a Lorentz force type of built-in motor, avoiding mechanical friction and material wear. The built-in motor is designed to generate only rotational torque, without radial and axial attractive forces on the rotor, leading to low power consumption by the magnetic bearing. The fabricated centrifugal pump measured 65 mm in diameter and 45 mm in height and weighed 0.36 kg. In the closed loop circuit filled with water, the pump provided a flow rate of 4.5 L/min at 2,400 rpm against a pressure head of 100 mm Hg. Total power consumption at that point was 18 W, including 2 W required for magnetic levitation, with a total efficiency of 5.7%. The experimental results showed that the design of the compact magnetic bearing was feasible and effective for use in a centrifugal blood pump.     

Study on stable equilibrium of levitated impeller in rotary pump with passive magnetic bearings

It is widely acknowledged that the permanent maglev cannot achieve stable equilibrium; the authors have developed, however, a stable permanent maglev centrifugal blood pump. Permanent maglev needs no position detection and feedback control of the rotor, nevertheless the eccentric distance (ED) and vibration amplitude (VA) of the levitator have been measured to demonstrate the levitation and to investigate the factors affecting levitation. Permanent maglev centrifugal impeller pump has a rotor and a stator. The rotor is driven by stator coil and levitated by two passive magnetic bearings. The rotor position is measured by four Hall sensors, which are distributed evenly and peripherally on the end of the stator against the magnetic ring of the bearing on the rotor. The voltage differences of the sensors due to different distances between the sensors and the magnetic ring are converted into ED. The results verify that the rotor can be disaffiliated from the stator if the rotating speed and the flow rate of the pump are large enough, that is, the maximal ED will reduce to about half of the gap between the rotor and the stator. In addition, the gap between rotor and stator and the viscosity of the fluid to be pumped also affect levitation. The former has an optimal value of ≈ 2% of the radius of the rotor. For the latter, levitation stability is better with higher viscosity, meaning smaller ED and VA. The pressure to be pumped has no effect on levitation.     

Study on stable equilibrium of levitated impeller in rotary pump with passive magnetic bearings

It is widely acknowledged that the permanent maglev cannot achieve stable equilibrium; the authors have developed, however, a stable permanent maglev centrifugal blood pump. Permanent maglev needs no position detection and feedback control of the rotor, nevertheless the eccentric distance (ED) and vibration amplitude (VA) of the levitator have been measured to demonstrate the levitation and to investigate the factors affecting levitation. Permanent maglev centrifugal impeller pump has a rotor and a stator. The rotor is driven by stator coil and levitated by two passive magnetic bearings. The rotor position is measured by four Hall sensors, which are distributed evenly and peripherally on the end of the stator against the magnetic ring of the bearing on the rotor. The voltage differences of the sensors due to different distances between the sensors and the magnetic ring are converted into ED. The results verify that the rotor can be disaffiliated from the stator if the rotating speed and the flow rate of the pump are large enough, that is, the maximal ED will reduce to about half of the gap between the rotor and the stator. In addition, the gap between rotor and stator and the viscosity of the fluid to be pumped also affect levitation. The former has an optimal value of approximately 2% of the radius of the rotor. For the latter, levitation stability is better with higher viscosity, meaning smaller ED and VA. The pressure to be pumped has no effect on levitation.     

Novel maglev pump with a combined magnetic bearing

The newly developed pump is a magnetically levitated centrifugal blood pump in which active and passive magnetic bearings are integrated to construct a durable ventricular assist device. The developed maglev centrifugal pump consists of an active magnetic bearing, a passive magnetic bearing, a levitated impeller, and a motor stator. The impeller is set between the active magnetic bearing and the motor stator. The active magnetic bearing uses four electromagnets to control the tilt and the axial position of the impeller. The radial movement of the levitated impeller is restricted with the passive stability dependent upon the top stator and the passive permanent magnetic bearing to reduce the energy consumption and the control system complexity. The top stator was designed based upon a magnetic field analysis to develop the maglev pump with sufficient passive stability in the radial direction. By implementing this analysis design, the oscillating amplitude of the impeller in the radial direction was cut in half when compared with the simple shape stator. This study concluded that the newly developed maglev centrifugal pump displayed excellent levitation performance and sufficient pump performance as a ventricular assist device.     

无叶片离心泵结构对体外循环关键参数的影响

目的探讨无叶片离心泵结构和体外循环关键参数之间的关系,为无叶片离心泵的优化设计提供理论依据和实践参考。方法采用计算流体动力学（computational fluid dynamics,CFD）方法对无叶片离心泵进行数值模拟,分析离心泵的结构和转速与血液流量、泵内流动状态、预充量之间的关系。结果叶轮与蜗壳之间距离一定时,两层叶轮结构比一层叶轮结构驱动血液能力强,但是预充量大;进出口导管直径小,有利于调节流量;泵体结构和叶轮转速影响泵内的血液速度分布,从而会对血液造成不同程度的破坏。结论无叶片离心泵结构和叶轮转速对体外循环流量的控制、泵内血液速度分布、预充量有很大影响。     

磁液悬浮离心血泵体外溶血的实验及耐久性实验

通过建立模拟循环管路系统来研究磁液悬浮离心血泵的溶血性能及机械稳定性。建立体外模拟循环管路系统,体外溶血实验中以新鲜羊血为循环介质,调节前负荷和后负荷分别为15、100 mmHg,血泵转速设定为2 900 rpm,测定血浆游离血红蛋白含量（FHb）和红细胞压积（Hct）,计算血泵标准溶血指数（NIH）;耐久性试验其他各项设定同体外溶血实验,循环介质改为甘油水溶液。在体外溶血实验中,测得磁液悬浮离心血泵NIH值为（0.0038±0.0008）g/100L;耐久性实验中血泵连续正常运转90 d,期间无卡壳、停泵等现象,电压、电流、转速稳定。该血泵溶血性能处于较高水平,机械性能稳定可靠,满足进一步进行动物实验的要求。     

In vitro testing of a novel blood pump designed for temporary extracorporeal support

Extracorporeal blood pumps are used as temporary ventricular assist devices or for extracorporeal membrane oxygenation. The ideal pump would be intrinsically self-regulating, carry no risk of cavitation or excessive inlet suction, be afterload insensitive, and valveless thus reducing thrombogenicity. Currently used technology, including roller, centrifugal, and pneumatic pulsatile pumps, does not meet these requirements. We studied a nonocclusive peristaltic pump (M-Pump) in two mock circulatory loops and compared the performance to a frequently used centrifugal pump and a modified prototype of the M-Pump (the BioVAD). The simple resistance loop consisted of the investigated pump, a fixed height reservoir at 150 mm Hg, and a variable inflow reservoir. The pulsatile circulation used a mock patient simulator with adjustable resistance elements connected to a pneumatic pulsatile pump. The M-Pump intrinsically regulated flow with changing preload, was afterload insensitive, and did not cavitate, unlike the centrifugal pump. The BioVAD also demonstrated these features and could augment output with the use of vacuum assistance. A nonocclusive peristaltic pump may be superior for short-term extracorporeal circulatory assist by mitigating risks of excessive inlet suction, afterload sensitivity, and thrombosis.