压电泵动力学分析与优化设计

发布时间：2018-01-25 20:33

本文关键词： 压电泵压电驱动动力学振动分析　出处：《吉林大学》2013年博士论文　论文类型：学位论文

【摘要】：压电泵是微小型流体泵研究的一个主要领域，其具有体积小、能量密度高、流量分辨率高及便于数字化控制等方面的优点。压电泵在检测设备、仪器仪表、机械及电器等领域具有广阔的应用前景，在国外已有成型的压电泵产品。通过对国内外研究及应用现状的分析可以看出，目前制约压电泵广泛应用的主要是由于压电泵与系统的结合过程中存在的问题，而目前并未出现对压电泵动力学特性的系统研究。本文结合国家高技术研究发展项目“血糖监测与胰岛素注射微系统”（项目编号：2011AA040406），国家自然科学基金项目“压电型气体隔膜泵设计理论与关键技术研究”（项目编号：51175213）和“多腔压电泵用作血泵的基础理论与试验研究”（项目编号：81171481）开展研究，以微小型压电泵为研究对象，进行了动力学特性的理论分析、仿真分析及试验研究。为微小型压电泵的设计与应用提供理论依据。具体研究内容如下： 1.压电振子输出力分析压电振子是压电泵的动力原件，在小变形理论的基础上建立等效集中力模型，并根据该模型对压电陶瓷的各部分尺寸参数与等效集中力的关系进行分析。讨论了泵用压电振子的选择方法及主要参数的选择依据。提出一种基于常用仪器的压电振子动力学参数的测试方法，并用其测试样机振子，得到样机中压电振子的动力学参数。通过所建立模型对振子设计中的相关参数进行了分析，得出了参数的选择次序及其常用范围内参数对所输出的等效集中力的影响规律，并通过试验验证了结论的正确性。 2.压电泵动力学分析压电泵存在一个最优的工作频率，其频率特性是影响输出性能的一个主要因素，而动力学模型的建立是研究其动态性能的基础。在静态特性的基础上对压电泵的动态工作状态进行描述，采用将阀与主振质量分离的方法简化压电泵结构，结合粘性流体的振动流动模型讨论压电泵动力学模型。用阻抗分析法研究压电泵的动态性能并验证理论分析结论，实验表明采用振子自身的等效刚度作为系统的总体刚度时，模型计算得到的频率与实际情况相差很大。将支撑引入振动系统中，从其结构形式及粘弹性特点的角度进行讨论，得到的改进的动力学系统模型可以很好的预测简化结构的动力学特性。对泵内过流区的各部分阻尼进行了研究，并将其引入到动力学系统中，用以分析各部分流阻对主振质量输出位移及运动的影响。 3.压电泵出流模型建立与分析要对压电泵进行优化，就要得到其输出力流量模型，而有阀泵的模型相对复杂难以直接得到，因此以工作流体连续运动的无阀泵为切入，得到模型后推广到有阀压电泵。首先对无运动部件阀构成的无阀泵的单向出流机理进行讨论，并将其容积效率特性与压电泵主振质量结合，建立压电泵的流量输出模型。在此基础上利用正反流阻差概念将有阀泵和无阀泵的出流机理进行统一，并建立有阀泵的简化模型。对阀的不完全关闭现象进行讨论，，进而得到压电泵在阀不完全关闭状态下的流量模型，最终对有阀泵一般状态下的出流特性进行讨论，对泵的最终输出特性进行预测，为泵阀设计提供一种新的方法。 4.压电泵部件优化设计与试验研究在压电泵动力学系统基础上，建立各部件设计参数与系统的动力学参数之间的关系，根据对压电泵性能要求优化各部件的结构尺寸。根据压电泵出流模型可知影响系统输出幅值的直接因素是阻尼，即过流区的流阻特性，因此进行过流区仿真分析；通过支撑的设计与选用控制压电泵的频率特性；建立阀结构参数与系统动力学参数的关系。对以上参数进行优化实验，最后通过阀与压电泵主振质量的频率匹配提高压电泵的输出性能，同时得到理想的频率特性。 5.负载对压电泵输出性能影响研究利用压电泵系统的基本动力学模型和流量模型可以对压电泵的结构参数进行优化。但由于压电泵的输出总功率较小，要将其应用于不同的工作状态下就要将其与具体的应用及负载相结合，对压电泵进行优化以实现更广泛的应用。首先分类讨论压电泵的外部负载，并分析其所输送介质特性对泵性能的影响，再对外部的环境温度对泵性能的影响进行研究，最后对影响最明显的气泡对压电泵性能的影响展开系统的分析。通过气泡的形成、两相流的流动状态及流型、气泡对系统动力学特性的影响及泵中界面特性的研究，得出气泡对压电泵输出性能的影响规律及其主要因素，在此基础上选择合理的方法增强压电泵的抗气泡能力。本文结合压电学、机械动力学、流体力学、流体动力学、材料学及电学相关理论对压电泵的动力学特性及应用进行讨论。研究工作为微小型压电泵的设计提供了一种新的理论方法，对同类结构的微小型流体输送设备的设计具有借鉴意义。
[Abstract]:Piezoelectric pump is a main field of micro fluid pump research, which has the advantages of small volume, high energy density, has the advantages of high resolution and easy digital flow control and so on. In the piezoelectric pump testing equipment, instrumentation, and has wide application prospect in field of mechanical and electrical appliances, piezoelectric pump products abroad through the analysis of forming. The domestic and foreign research and application status of it can be seen that the current constraints of piezoelectric pump widely used is mainly due to the presence of the piezoelectric pump system and the problems in the process, and is currently no systematic research on dynamic characteristics of piezoelectric pump.
In this paper, combined with the national high technology research and development project "blood glucose monitoring and insulin injection micro system" (project number: 2011AA040406), National Natural Science Fund Project "the piezoelectric type gas diaphragm pump design theory and key technology research" (project number: 51175213) the basic theory and experimental research and multi chamber piezoelectric pump for blood pump "(project number: 81171481) to carry out research, a miniature piezoelectric pump as the research object, analyzes the dynamic characteristics of the theoretical analysis and experimental study of simulation. The design and application of mini type piezoelectric pump provides a theoretical basis. The specific contents are as follows:
Analysis of the output force of 1. piezoelectric vibrators
The piezoelectric vibrator is the original power of the piezoelectric pump, the equivalent concentrated force model based on small deformation theory, and according to the model to analyze the relationship between the size of each part of the parameters and equivalent concentrated force of piezoelectric ceramics is discussed. Choice based on pump selection method of piezoelectric vibrator and main parameters a commonly used instrument. The piezoelectric vibrator based on dynamic parameters testing method and the testing of prototype oscillators, dynamic parameters of piezoelectric vibrator prototype. Through the model parameters of the oscillator design analysis, influence of choice of the parameters are obtained and the common scope within the parameters of equivalent output concentration, and the correctness of the conclusion is verified by experiment.
Dynamic analysis of 2. piezoelectric pump
The working frequency of the piezoelectric pump has an optimal, its frequency characteristic is a major factor affecting the output performance, and dynamic modeling is based on its dynamic performance. The dynamic state of the piezoelectric pump based on the static characteristics of the description, the quality of the valve and the main vibration isolation a simplified piezoelectric pump structure, combined with the vibration flow model of viscous fluid on the piezoelectric pump dynamics model. Conclusion the method of piezoelectric pump dynamic performance and validate the theoretical analysis by impedance analysis, experiments show that the oscillator equivalent stiffness of the system as the overall stiffness is calculated by the model frequency and the difference between the actual situation great. Will support the introduction of vibration system, from its structure and viscoelastic characteristics are discussed from the perspective of system dynamics, the model can well predict the improved simplified dynamic structure The damping of all parts in the pump area is studied, and it is introduced into the dynamic system to analyze the influence of the flow resistance of each part on the output and displacement of the main vibration.
The establishment and analysis of the flow model of 3. piezoelectric pump
The piezoelectric pump is optimized to get the output power flow model, and valve pump model is relatively complex to directly, so the valve pump working fluid in continuous motion as the breakthrough, get after the model is extended to the valve pressure electric pump. Firstly, no moving parts composed of one-way flow valve discuss the mechanism of the valveless pump, and the volumetric efficiency and characteristics of piezoelectric pump vibration quality with establishing flow output model of piezoelectric pump. On the basis of the positive and negative difference resistance flow will have valve pump and valve pump flow mechanism and the establishment of a unified, simplified model of pump valve not completely closed. Phenomenon of valve are discussed, and then get the piezoelectric pump in the valve is not completely closed flow model under the condition of a final, discussed the flow characteristics of valve pump in general condition, the final output characteristics of the pump provides a forecast for the valve. A new method.
Optimum design and experimental study of 4. piezoelectric pump components
In the piezoelectric pump dynamic system based on the relationship between the kinetic parameters of parts design parameters and system, according to the structure size of the piezoelectric pump performance requirements optimized components. Based on the piezoelectric pump flow model that directly affects the system output amplitude is damped, namely the flow characteristics of flow area. Therefore, to analyze the simulation flow; through the support of the design and selection of control frequency characteristics of piezoelectric pump; relationship between valve structure parameters and dynamic parameters of the system. The optimization experiments on the above parameters, finally improve the output performance of piezoelectric pump with valve piezoelectric pump and the main vibration frequency, quality and frequency. The characteristics of the ideal.
Study on the effect of 5. load on the output performance of a piezoelectric pump
By using the basic dynamics model and flow model of piezoelectric pump system on structure parameters of piezoelectric pump are optimized. But because the total power output of the piezoelectric pump is smaller, it will be used in different working conditions will be combined with the load and the specific application phase of piezoelectric pump is optimized to to achieve a more widespread application. First discuss external piezoelectric pump load, and analyze the characteristics of the transmission medium impact on pump performance, to study the effects of external environment temperature on the performance of the pump, the most obvious influence of bubbles on the influence of piezoelectric pump performance analysis system. Through the bubble expansion the formation of flow state and flow pattern of two-phase flow, interface characteristic of the bubble effect on the dynamic characteristics of the system and the pump, get the influence law of bubbles on the piezoelectric pump output performance and main factors, on the basis of selection A reasonable method can be used to enhance the anti bubble ability of the piezoelectric pump.
This combination of piezoelectricity, mechanical dynamics, fluid mechanics, fluid dynamics, dynamic characteristics and application of material science and electrical related theory of piezoelectric pump are discussed. It provides a new theory method design of the piezoelectric pump is small, has the reference significance for design of micro fluid conveying equipment of similar structure.

【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TH38

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