弯曲摆动无阀式压电泵理论分析与模拟

设计一种新型弯曲摆动无阀式压电泵,并对其进行理论分析,根据压电泵的尺寸、结构和动力学模型,对压电振子的位移响应进行分析;采用有限元分析的方法利用该公式函数对弯曲摆动式无阀压电泵进行仿真分析,得到该压电泵的内部流场特性,得到该压电泵出入口流速和内部压强的变化情况.对本文压电泵输出流量与频率的关系进行分析,结果表明:压电泵在工作频率在左右达到最大输出流量,具有较好的输出流量特性.     

悬臂梁阀单腔压电泵设计方法研究

给出了悬臂梁阀单腔压电泵的理论分析,根据压电振子与流体耦合的理论,建立了压电泵系统的动态模型.分析了流体质量、输出压力和系统阻尼对压电泵最佳工作频率的影响,认为减小腔体高度可以提高压电泵的最佳工作频率,提高压电泵的稳定性.通过分析压电振子结构参数对变形量的影响规律,确定了振子的最佳结构参数,认为压电陶瓷层与金属基板厚度比取0.45～0.55,直径比取0.8～0.9最佳.研究了压电泵出流形式对压电泵输出能力的影响,认为轴後向出流有利于提高压电泵的输出能力.     

压电泵的研究--泵阀滞后性

就有阀压电泵增频流量骤减现象进行了分析与研究.发现了现有提高频率使压电振子振幅减小为增频流量骤减现象主要成因的说法是一种错误解释,并通过试验证明了现有理论的非正确性.提出了解释增频流量骤减现象成因的泵阀滞后性模型,同时开发了观察这种现象的具体新方法及观测新装置,并利用这一新装置观察到了泵阀滞后现象.提出了可以评价、考察有阀压电泵的泵阀的量化值--滞后系数,并把其作为泵阀优化设计的具体目标.     

声控无阀压电喷流泵

提出了一种声控无阀压电喷流泵,利用声控电路控制压电泵开启、关闭并控制其喷流状态,实现了无需信号发生器而直接驱动压电泵工作.阐述了声控电路没计结构和工作机理,设计并加工了声控振荡电路和声控开关电路板,并与无阀压电喷流泵匹配进行了系统调试.实验结果表明:压电泵喷流状态随外界声音频率、振幅变化而变化,声音频率越高、振幅越大,压电泵喷流高度增高,出水量增大;当声音频率与压电泵基频产生共振时,压电泵达到最佳喷流效果.     

单振子双腔体无阀压电泵结构设计与机理分析

提出了一种单振子双腔体无阀压电泵,应用小挠度弹性弯曲理论导出了圆形复合压电振子的弹性曲面微分方程,分析了采用一个压电振子形成两个工作腔体压电泵的结构和工作机理,并与单振子单腔体压电泵对比分析了该结构与输出流量的关系。设计研制了结构独特、输出性能更高的单振子双腔体无阀压电泵,通过试验表明:单振子双腔体无阀压电泵比单振子单腔体无阀压电泵输出流量有明显提高。     

"Y"形流管无阀压电泵模拟与试验

对"Y"形流管无阀压电泵内部流场及泵流量特性进行了模拟及试验研究.采用CFX软件对"Y"形流管无阀压电泵泵腔内的流场特性进行了模拟分析.结果表明:"Y"形流管无阀压电泵工作时泵腔内的压强变化很小,涡旋对流体传输活体细胞及长链大分子基本无影响.实际制作了"Y"形流管无阀压电泵,并通过改变"Y"形流管的几何尺寸,研究了压电泵进出口端压差的变化规律.试验结果表明,压差随支管夹角增大而减小,并且当两支管宽的和接近主管宽时,压差值达到最小,当支管夹角为5°,宽为1.2 mm时,压差达到最大725 Pa.     

压电泵振动放射噪声的两种理论模型

研究压电泵振动放射噪声,提出两种由振动量计算压电泵合成声压的理论模型.     

无阀压电泵的流固耦合仿真及试验验证

提出利用结构分析软件ANSYS和流体分析软件ANSYS CFX对无阀压电泵进行流固耦合仿真分析,以研究无阀压电泵的输出性能。分别对进口在中间出口在一侧、出口在中间进口在一侧、进出口对称布置的3种不同结构形式的无阀压电泵进行了流固耦合仿真分析。结果显示,上述3种无阀压电泵中,出口在中间进口在一侧结构形式的无阀压电泵的宏观输出流量最大。制作了3种无阀压电泵的试验样机,并搭建了相应的试验测试系统,在幅值为45 V、频率为0~700Hz的正弦信号激励下对其输出流量进行了测试。结果表明,3种不同结构形式的无阀压电泵的最大输出流量分别为3.8、6.0和4.0ml/min,出口在中间进口在一侧的压电泵输出流量最大,与流固耦合仿真分析的结果相吻合,验证了本文提出的流固耦合仿真分析的方法可以指导压电泵的设计。     

基于DSP的三相压电泵驱动电源

设计一套关于于DSP的三相压电泵驱动电源.整个驱动电源由一个高性能的处理器DSP2812、反激变换器、三相逆变拓扑结构、按键输入和LCD输出系统组成,能满足各种压电泵的驱动方式,实现输出电压、电压相位和电压频率同时调节的功能,对压电泵的研究具有重要的实践意义.     

钹型开槽式阀压电泵的设计

由于有阀压电泵内部阀体所受应力过大易导致阀体失效,本文提出了钹型开槽式截止阀来减小有阀压电泵内部阀体所受应力。基于钹型开槽式截止阀设计了有阀压电泵,分析了钹型开槽式阀压电泵的工作原理。对钹型开槽膜片进行了受力分析,研究了该压电泵的输出性能及耦合作用下的膜片应力。加工制作了钹型开槽式阀压电泵样机,建立了钹型开槽式阀压电泵的有限元模型,数值计算了流固耦合作用下的阀体应力值。计算结果表明:在压电泵正常输出的驱动频率范围内,当驱动频率为418Hz时,膜片所受应力的计算值也达到最大,为81.74 MPa。最后,进行了压电泵性能试验。试验结果显示:该压电泵的输出流量最大值和振子振幅最大值均出现在低频段;当驱动电压为160V,驱动频率为5Hz时,输出流量达到最大,为6.6g/min;驱动频率为4Hz时,压电振子振幅达到最大,为165.8μm。文中的研究验证了钹型开槽式阀体压电泵的有效性,并得出当钹型开槽式阀压电泵工作在低频段时,阀门所受应力远小于高频段时阀门的应力值。     

半柔性阀压电泵理论与实验

根据静脉瓣结构形式,设计了一种半柔性阀压电泵。首先,介绍了半柔性阀压电泵的结构及工作原理;其次,对阀体进行了理论分析;最后,加工了实验样机,对样机进行性能测试实验。实验结果表明:在驱动电压为220V、频率为7Hz时,半柔性阀压电泵的进出口压差可达到199mm;在驱动电压为220V、频率为11Hz时,半柔性阀压电泵的实验流量为44.5ml/min。随着驱动电压的升高,工作频率与流量出现单峰与双峰的现象。该研究证明了半柔性阀压电泵具有泵的功能并可以实现有阀和无阀状态,验证了其有效性和理论分析的正确性。     

双腔体压电泵的设计

由于自吸性差、对气泡敏感等原因,单腔体压电泵在应用中受到限制,而多腔体结构是提高压电泵性能的有效途径.通过分析腔体容积与压力变化过程得出:双腔体串联压电泵只能采用串联驱动方式而不能采用并联驱动方式,双腔体并联压电泵只能采用并联驱动方式而不能采用串联驱动方式.制作双腔串联、并联压电泵样机并进行测试可以得出:串联压电泵在驱动电压200 V,频率152 Hz时,输出流量达到最大为1 150 ml/min;并联泵在压电驱动电压140 V,频率220 Hz时,输出流量达到最大为640 ml/min;因此多腔泵采用腔体串联结构能提高压电泵的工作效率,提高泵的工作性能.     

螺旋线形阀压电泵的理论与试验研究

有阀压电泵在精细化工、MEMS、生物医学工程等领域具有重大应用前景。为了克服有阀压电泵结构复杂、跟从与截止性差、成本高等缺点,设计一种异形拟悬臂梁结构的螺旋线形弹性固支阀,其螺旋臂长是简单悬臂梁阀的数倍,工作时开启度大,且因其螺旋线形弹性结构,阀体不仅可以上下回位,左右也具有对中功能,并把这种阀安装在有阀压电泵的泵腔内形成螺旋线形阀压电泵。在深入分析有阀压电泵优缺点的基础上分析螺旋线形阀压电泵的工作原理,依照泵内部能量传递的路径建立压电驱动(电压、频率)为输入与泵流动(流量、压差)为输出之间的关系式,加工试验样机,并进行性能测试试验,螺旋线形阀压电泵具有泵功能,证明了其有效性和理论分析的正确性。试验结果表明:随着驱动电压的增大,泵的输出流量和压差呈上升趋势,这个结果与Matlab数值仿真计算结果趋势一致。在电压为220 V、频率为30 Hz时,得到仿真流量41.26m L/min,实际试验流量为10.2 m L/min,误差75.3%;在电压为220 V、频率为20 Hz时,得到仿真流量27.51 m L/min,实际试验流量为22.8 m L/min,误差17.2%。     

Theoretical analysis and experimental investigation of valveless piezoelectric pump with unsymmetrical ridges

A novel valveless piezoelectric pump with unsymmetrical ridges is presented at first. It ingeniously utilizes the inner space of its chamber by developing its chamber bottom into unsymmetrical ridges along the direction of the inlet and outlet of the pump. Hence, a series of cuneiform channels are asymmetrically and alternately formed between the unsymmetrical ridges and the piezoelectric vibrator, which enables the pump to form a one-way flow instead of the function of the traditional diffuse or nozzle elements fitted outside the chamber. Then, by analyzing the vibration of the piezoelectric vibrator, the vibration deformation function and the equation of volume change are established. Meanwhile, the theoretical equation of the pump flow rate is established. Finally, a real valveless piezoelectric pump with unsymmetrical ridges is manufactured, and the flow rate of the pump is measured through experiments. It is proved that the theory is rational and correct by comparing the experimental flow rate and the theoretical flow rate. In addition, for calculating the theoretical flow rate, the positive and converse flow resistance coefficients of unsymmetrical ridges are measured through experiments, when one slope angle of the unsymmetrical ridges is 90° and another is changing from 20° to 60°, respectively.     

泵用压电振子动态特性的研究

为了提高压电泵的效率、优化压电泵的结构,对泵用压电振子的动态特性进行了研究。介绍了一种新型压电泵——Y形流管无阀压电泵的结构和工作原理;对Y形流管无阀压电泵压电振子的振动状态进行了理论分析,得到了压电振子的固有频率及最大振幅的理论计算公式,并证明了理论分析结果的正确性;根据理论分析结果,对压电振子几何参数和基底层材料对其振动特性的影响进行了分析讨论。分析结果表明：压电振子的PZT层与基底层的直径比应在0.75左右,厚度比应小于1;基底层材料对频率影响较大,但对最大振幅影响较小。     

Theory and experimental verification on valveless piezoelectric pump with multistage Y-shape treelike bifurcate tubes

Among most traditional piezo water cooling systems, piezoelectric valve pumps are adopted as their driving sources. The valves in these pumps induce problems of shock and vibration and also make their structure complicated, which is uneasy to minimize and reduce their reliability and applicability of the whole system. In order to avoid these problems caused by valve structure, a novel valveless piezoelectric pump is developed, which integrates both functions of transforming and cooling. The pump’s Y-shape tree-like construction not only increases the efficiency of cooling but also the system reliability and applicability. Firstly, a multistage Y-shape treelike bifurcate tube is proposed, then a valveless piezoelectric pump with multistage Y-shape treelike bifurcate tubes is designed and its working principle is analyzed. Then, the theoretical analysis of flow resistance characteristics and the flow rate of the valveless piezoelectric pump are performed. Meanwhile, commercial software CFX is employed to perform the numerical simulation for the pump. Finally, this valveless piezoelectric pump is fabricated, the relationship between the flow rates and driving frequency, as well as the relationship between the back pressure and the driving frequency are experimentally investigated. The experimental results show that the maximum flow rate is 35.6 mL/min under 100 V peak-to-peak voltage (10.3 Hz) power supply, and the maximum back pressure is 55 mm H2O under 100 V (9 Hz) power supply, which validates the feasibility of the valveless piezoelectric pump with multistage Y-shape treelike bifurcate tubes. The proposed research provides certain references for the design of valveless piezoelectric pump and improves the reliability of piezo water cooling systems.     

Simulation analysis and experimental verification of spiral-tube-type valveless piezoelectric pump with gyroscopic effect

The current research of the valveless piezoelectric pump focuses on increasing the flow rate and pressure differential. Compared with the valve piezoelectric pump, the valveless one has excellent performances in simple structure, low cost, and easy miniaturization. So, their important development trend is the mitigation of their weakness, and the multi-function integration. The flow in a spiral tube element is sensitive to the element attitude caused by the Coriolis force, and that a valveless piezoelectric pump is designed by applying this phenomenon. The pump has gyroscopic effect, and has both the actuator function of fluid transfer and the sensor function, which can obtain the angular velocity when its attitude changes. First, the present paper analyzes the flow characteristics in the tube, obtains the calculation formula for the pump flow, and identifies the relationship between pump attitude and flow, which clarifies the impact of flow and driving voltage, frequency, spiral line type and element attitude, and verifies the gyroscopic effect of the pump. Then, the finite element simulation is used to verify the theory. Finally, a pump is fabricated for experimental testing of the relationship between pump attitude and pressure differential. Experimental results show that when Archimedes spiral θ=4π is selected for the tube design, and the rotation speed of the plate is 70 r/min, the pressure differential is 88.2 Pa, which is 1.5 times that of 0 r/min rotation speed. The spiral-tube-type valveless piezoelectric pump proposed can turn the element attitude into a form of pressure output, which is important for the multi-function integration of the valveless piezoelectric pump and for the development of civil gyroscope in the future.     

多级“Y”型流管无阀压电泵的原理与试验验证(实验视频)

针对目前微流体混合器多需要外接动力源,且多数微混合器只能进行液体混合而不能输送液体的问题,提出将无阀压电泵引入微混合器领域,并研制了一种集混合与输送于一体的多级“Y”型流管无阀压电泵。首先,提出了多级“Y”型流管,进而设计了多级“Y”型流管无阀压电泵,并分析其工作原理;然后,对该无阀压电泵的流管流阻特性及泵流量进行理论分析;同时,利用有限元软件对多级“Y”型流管无阀压电泵进行了流场模拟,结果表明该压电泵具有单向传输作用。最后,制作了多级“Y”型流管无阀压电泵样机,并进行了泵流量与背压试验。试验结果显示：驱动电压峰峰值为100 V,频率为16 Hz时,流量达到最大,为16.2 ml/min;驱动电压峰峰值为100 V,频率为14 Hz时,输出背压最大,约为64 mm水柱。得到的试验数据证明了多级“Y”型流管无阀压电泵的有效性。(实验视频)     

一种仿生型无阀压电泵

针对传统的容积型流阻差式无阀压电泵具有吸入周期和排出周期,存在着流动脉动大、流量小的问题,提出一种新型的鱼鳍摆动式无阀压电泵。模仿在鱼类中巡游速度最快的金枪鱼的鱼体结构,设计了压电双晶片结构的压电振子,并将其尾鳍设计成柔性叶片状。分析了压电双晶片结构悬臂梁的受力变形、模态振型在机电转换效率方面的关系。研制了泵的样机并测量了激励电压在100 V时泵的流量。实验结果表明:振子工作在1阶振型时,泵水效应不明显;振子工作在2阶振型时,谐振频率为740 Hz,泵的流量为266 mL/min;振子工作在3阶振型时,谐振频率为1 280 Hz,泵的流量为105 mL/min。     

3D FEM analyses on flow field characteristics of the valveless piezoelectric pump

Due to the special transportation and heat transfer characteristics, the fractal-like Y-shape branching tube is used in valveless piezoelectric pumps as a no-moving-part valve. However, there have been little analyses on the flow resistance of the valveless piezoelectric pump, which is critical to the performance of the valveless piezoelectric pump with fractal-like Y-shape branching tubes. Flow field of the piezoelectric pump is analyzed by the finite element method, and the pattern of the velocity streamlines is revealed, which can well explain the difference of total flow resistances of the piezoelectric pump. Besides, simplified numerical method is employed to calculate the export flow rate of piezoelectric pump, and the flow field of the piezoelectric pump is presented. The FEM computation shows that the maximum flow rate is 16.4 mL/min. Compared with experimental result, the difference between them is just 55.5%, which verifies the FEM method. The reasons of the difference between dividing and merging flow resistance of the valveless piezoelectric pump with fractal-like Y-shape branching tubes are also investigated in this method. The proposed research provides the instruction to design of novel piezoelectric pump and a rapid method to analyse the pump flow rate.