多振子压电泵的结构设计及应用研究

发布时间：2018-10-20 13:54

【摘要】：压电泵是利用逆压电效应来驱动介质的一种流体泵，它具有结构简单、体积小、重量轻，寿命长，可靠性高等优点。查阅相关文献可知，国内外对压电泵的研究工作主要集中在提高性能参数（输出压力、输出流量、输出精度）和保证输出性能前提下降低功耗等方面。本论文来源于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》。本项目主要是对多振子压电泵结构进行设计与优化，并进行相关试验，验证多腔压电泵用作人工心脏泵的可能性。本论文的研究内容如下：基于板壳理论与弹性力学中的轴对称薄圆板的小挠度问题，建立了环形压电振子的理论弯曲模型，推导出环形压电振子容积变化的影响因素，并对论文中所用到的环形压电振子的变形量进行了实验测试。设计了一种多振子压电泵结构，并对压电泵的腔高、进出口直径以及阀片的选取进行了优化；对单振子压电泵的单向阀进行动力学分析，采用阀片和振子质量分离的方法简化压电泵结构。分别讨论了由压电振子的运动所提供的惯性力作为驱动力以及由压电振子的振动而产生的压差作为驱动力致使阀片开启的影响因素，推导出由惯性力引起阀片开启和由压差引起阀片开启的开度公式。根据两个公式可知，单向阀的开度取决于外界激励和系统自身的参数。对单振子压电泵的单向阀进行实验分析，得到不同频率下单振子压电泵阀片开启的主要影响因素。最后，介绍了单振子、双振子以及三振子压电泵的结构以及在不同工作状态下的工作原理。制作压电泵的实验样机，通过实验测试了单振子、双振子以及三振子压电泵的输出性能；探索出不同工作方式、工作振子数目以及阀片数量对压电泵输出性能的影响。实验结果表明：①从输出流量来看，随着振子数目的增加，最佳工作频率越来越小，在频率为40Hz~220Hz时，输出流量随着振子数目的增加而略有增加，在频率220Hz~400Hz时，输出流量随着振子数目的增加而减小；②从输出压力来看，随着振子数目的增加，输出压力有显著的提高，当工作频率为140Hz时，三振子压电泵异步工作时的输出压力为4.08kPa；三振子压电泵振子1不工作，振子2、3异步工作时的输出压力要明显好于双振子压电泵异步工作时的输出压力，同时，三振子压电泵振子3单独工作时的输出压力要好于双振子压电泵振子2单独工作时的输出压力，双振子压电泵振子2单独工作时的输出压力要好于单振子压电泵的输出压力。制作多种实验样机进行甘油模拟血液实验，得出不同腔高，不同阀片以及不同阀片厚度对压电泵输出性能的影响。推导出压电泵工作过程中的轴向压力梯度，并建立了红细胞膜的模型方程，，制作实验样机进行压电泵工作时间对血细胞的影响实验，并通过使用光学显微镜观察细胞形态。
[Abstract]:Piezoelectric pump is a kind of fluid pump which uses inverse piezoelectric effect to drive medium. It has the advantages of simple structure, small volume, light weight, long life, high reliability and so on. According to the related literatures, the research work of piezoelectric pump at home and abroad mainly focuses on improving the performance parameters (output pressure, output flow rate, output precision) and reducing power consumption under the premise of ensuring output performance. This paper comes from the project of National Natural Science Foundation, the basic theory and experimental study of multichamber piezoelectric pump as blood pump. This project is mainly to design and optimize the structure of multi-vibrator piezoelectric pump, and carry out related tests to verify the possibility of using multi-chamber piezoelectric pump as artificial heart pump. The main contents of this thesis are as follows: based on the theory of plate and shell and the problem of small deflection of axisymmetric thin circular plate in elastic mechanics, the theoretical bending model of ring piezoelectric oscillator is established. The influence factors of the volume variation of the ring piezoelectric oscillator are deduced, and the deformation of the ring piezoelectric oscillator used in this paper is tested experimentally. A multi-vibrator piezoelectric pump structure is designed, and the cavity height, inlet and outlet diameter of piezoelectric pump and the selection of valve plate are optimized, and the dynamic analysis of unidirectional valve of single vibrator piezoelectric pump is carried out. The structure of piezoelectric pump is simplified by means of mass separation of valve plate and vibrator. The inertial force provided by the motion of the piezoelectric vibrator as the driving force and the pressure difference caused by the vibration of the piezoelectric vibrator as the driving force are discussed respectively. The opening formula for opening the valve plate caused by inertial force and by pressure difference is derived. According to the two formulas, the opening degree of the one-way valve depends on the external excitation and the parameters of the system itself. Based on the experimental analysis of the single vibrator piezoelectric pump valve, the main factors influencing the opening of the valve plate of the order oscillator piezoelectric pump with different frequencies are obtained. Finally, the structure and working principle of single oscillator, double oscillator and three vibrator piezoelectric pump are introduced. The experimental prototype of piezoelectric pump is made, and the output performance of single oscillator, double oscillator and three vibrator piezoelectric pump is tested experimentally, and the effects of different working modes, number of working vibrators and the number of valve plates on the output performance of piezoelectric pump are explored. The experimental results show that: 1 from the point of view of the output flux, with the increase of the number of vibrators, the optimal operating frequency becomes smaller and smaller. When the frequency is 40Hz~220Hz, the output flow rate increases slightly with the increase of the number of vibrators, and at the frequency of 220Hz~400Hz, The output flow rate decreases with the increase of the number of oscillators, 2 from the point of view of the output pressure, the output pressure increases significantly with the increase of the number of vibrators, and the output pressure of the three-oscillator piezoelectric pump is 4.08 KPA when the operating frequency is 140Hz. The output pressure of the three vibrator piezoelectric pump oscillator 1 is obviously better than that of the double oscillator piezoelectric pump when it works asynchronously, and at the same time, The output pressure of the three vibrator piezoelectric pump vibrator 3 is better than that of the double oscillator piezoelectric pump oscillator 2 working alone. The output pressure of the double oscillator piezoelectric pump oscillator 2 is better than that of the single vibrator piezoelectric pump. The effects of different cavity height, different valve plate and different valve thickness on the output performance of piezoelectric pump were obtained by making a variety of experimental prototypes to simulate the blood of glycerin. The axial pressure gradient during the operation of the piezoelectric pump was derived, and the model equation of erythrocyte membrane was established. The experimental prototype was made to test the effect of the working time of the pump on the blood cells, and the morphology of the cells was observed by optical microscope.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TH38

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