压电驱动血液泵的设计及实验研究

发布时间：2018-06-10 16:36

本文选题：血液泵 + 压电驱动　；参考：《吉林大学》2014年硕士论文

【摘要】：人工血液泵，即人工心脏，是置于患者体内或体外全部或者部分代替自然心脏以实现血液循环的一种机械装置。按用途将人工心脏分为左心室辅助、右心室辅助以及全人工心脏等多种类型，其中一个完整的系统应当包括液体驱动装置、监测系统与控制机构、能源供给机构（电池）等部分，其核心部件是液体驱动装置，也就是血液泵。血液泵的输出性能要满足生物体的生理需求，应具有高稳定性、低溶血及生物相容性好的特点，同时应该具有体积小、重量轻的特性以满足携带或体内植入的要求。本文提出将压电泵作为血液泵，压电泵是一种以逆压电效应驱动介质的新型流体泵，工作过程中对周围环境无电磁干扰。本文设计的压电驱动血液泵内部无旋转部件，驱动源运动速度较低，在血液驱动过程中冲击性小，避免了血液凝聚和血细胞的破坏。本文结合国家自然科学基金项目“多腔压电泵用作血泵的基础理论与试验研究”(81171481)的技术要求，研究用于临床前期实验的具有完全知识产权的新型人工心脏泵系统。本项目基于前期课题的研究经验，采用以试验为主，理论分析与仿真分析相结合的研究方案。本文从压电驱动血液泵的腔高、缓冲腔深度、进出口直径、截止阀结构等几个方面研究血液泵结构对性能的影响。首先，通过理论分析建模，分析影响血液泵输出特性的因素；其次，通过单因素对比实验法，对不同结构参数的血液泵进行实验研究，根据实验结果优选出最优结构；最后，搭建体外循环系统，对试验样机进行测试和分析。使用试验样机搭建模拟的体外循环系统进行试验，，通过全自动血细胞分析仪分别对体外循环0.5小时、1小时、1.5小时后的血液进行检测。检测结果发现红细胞计数、白细胞计数、淋巴细胞、血红蛋白、血细胞压积几项参数指标随着体外循环时间的延长均有减小的趋势，循环时间越长对血细胞的破坏程度也随之增加，但破坏程度明显低于传统连续式血液泵。试验发现在压电驱动血液泵内部泵壁拐角处血细胞破坏后形成了絮状的凝结物，理论分析表明这种破坏是血液从入口管道进入泵腔区域时，过流区的截面突然扩大在压电驱动血液泵内部泵壁拐角处产生湍流效应引起的。在体外循环后发现悬臂梁阀片上所积累的絮状凝结物少于轮式阀片上所积累的絮状物，因此悬臂梁阀结构对血细胞的破坏程度小于轮式阀。
[Abstract]:Artificial blood pump (artificial heart) is a kind of mechanical device which is placed in the patient's body or in vitro to replace the natural heart in whole or in part in order to realize blood circulation. The artificial heart is divided into several types according to its use: left ventricular assist, right ventricular assist and total artificial heart. One of the complete systems should include fluid drive device, monitoring system and control mechanism. Energy supply mechanism (battery) and other parts, the core component is a liquid driving device, that is, blood pump. The output performance of blood pump should be high stability, low hemolysis and good biocompatibility in order to meet the physiological needs of organism, and it should be small in size. The piezoelectric pump is a new type of fluid pump driven by inverse piezoelectric effect, and there is no electromagnetic interference in the working environment. The piezoelectric driving blood pump designed in this paper has no rotating parts inside, so the driving source has low speed and low impact in the process of blood driving. This paper combines with the project of National Natural Science Foundation "basic theory and experimental study of multi-chamber piezoelectric pump as blood pump" to avoid the destruction of blood coagulation and blood cell. A new type of artificial heart pump system with full intellectual property rights was studied for clinical trials. Based on the previous research experience, this project adopts the research scheme which is based on experiment, theoretical analysis and simulation analysis. In this paper, the cavity height, buffer cavity depth, inlet and outlet diameter of blood pump driven by piezoelectric are introduced. The effect of the structure of blood pump on performance was studied in several aspects, such as the structure of globe valve. Firstly, through theoretical analysis and modeling, the factors that affect the output characteristics of blood pump are analyzed. Secondly, the experimental study of blood pump with different structure parameters is carried out by the method of single factor contrast experiment, and the optimal structure is selected according to the experimental results. Set up the external circulation system, test and analyze the test prototype, use the test prototype to set up the simulated external circulation system to carry on the experiment, The blood samples after CPB were measured by automatic hematology analyzer after 1 hour and 1.5 hours after cardiopulmonary bypass (CPB). The results showed that red blood cell count, white blood cell count, lymphocyte, hemoglobin and hematocrit decreased with the prolongation of cardiopulmonary bypass time. The longer the circulation time, the more damaged the blood cells were, but the degree of destruction was obviously lower than that of the traditional continuous blood pump. The experiment found that the blood cells destroyed at the corner of the pump wall of the piezoelectric driven blood pump formed flocculent coagulant. Theoretical analysis shows that this kind of destruction is caused by the turbulent effect at the corner of the pump wall of the piezoelectric driven blood pump when the cross section of the flow zone expands suddenly when the blood enters the pump cavity from the inlet pipe. After cardiopulmonary bypass, it was found that the flocculent coagulant accumulated on the cantilever valve was less than that on the wheeled valve, so the damage degree of the cantilever valve to blood cells was less than that of the wheeled valve.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TH789

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