| 1,IntroduceThis part gives us a mainly introduction to the piezoelectric-pump about home and abroad,and expatiates the characteristics and the working principles,and analyses the development trend.The piezoelectric-pump driven by piezoelectric-stack is a newly development trend,it can accommodate frequency and pressure in a large scale and control the output flux in precision.This pump will widely apply to transfusion,feed oil and clean the equipment in industrial automation,and scientific research,lab, chemical preparation and cooling of CPU etc.2,The basic principle of piezoelectric ActuationThis chapter introduces the basic knowledge of piezoelectric materials, including piezoelectric effect and electrostrictive effects. Piezoelectric materials and Electro stretching material, the relevant parameters of piezoelectric materials, piezoelectric equation, and the types of piezoelectric materials. Then piezoelectric actuator technology is briefly described, the main structure of the piezoelectric actuator type and application. Actuator characteristics : its larger output power per unit weight; Flexible start and stop quickly; Low speed, large torque; Structure flexible; Minimal magnetic interference.3,Piezoelectric-stackThe present chapter describes the piezoelectric multilayer structure and working principle and features. Piezoelectric multilayer comparison with the electromagnetic actuator with a lot of advantages : excellent response, the high positioning resolution. not produce electromagnetic noise and low power consumption characteristics. And the double-chip-type actuators, compared with piezoelectric multilayer high-energy conversion efficiency, low power consumption,output power and high response speed, the output displacement stable and less creep phenomena. Compared with the accumulation type actuators, piezoelectric stack heap with a small volume, low-voltage, low-cost and easy to apply. It also introduces the main characteristics of typical piezoelectric multilayer including hysteresis characteristics, creep properties, temperature and pressure characteristics, Hysteresis and stiffness properties and methods for the elimination of six points.4,Structural design and analysis on the Piezoelectric Stack PumpFrom the perspective of structural optimization and design of this chapter, the reactor stack of piezoelectric pump structure, and its working principles and processes.Comparison of the advantages and disadvantages of several commonly passive cut-off valve. As finally adopted a passive valve lower-cost umbrella rubber valve Analysis of the umbrella and rubber valve principle and hysteresis. The design of a piezoelectric multilayer pump pads, and the use of finite element analysis methods for analysis. Since piezoelectric pump, fluid and strong coupling between the piezoelectric oscillator, This chapter of the former body fluid pressure distribution were studied. According to various export position, and to discuss and analyze the axial and radial flow out of the flow when the body cavity fluid pressure distribution. Axial out that the use of piezoelectric pump flow is conducive to raising output capacity, and the diameter decreases with increased output pressure.5,Test and Research on the Piezoelectric Stack PumpOn the basis of previous chapters, we have designed a piezoelectric multilayer pump developed. This chapter of the reactor stack of piezoelectric pump flow, pressure-voltage and frequency characteristics of the test analysis, Through analysis of the impact test reactor stack of piezoelectric pump optimal frequency. The impact of the trial on the basis of export performance of piezoelectric multilayer pump different factors are analyzed. Valve hysteresis of the analysis ANSYS software stack and heap of piezoelectric pump cavity flow field of finite element analysis. stack of piezoelectric pump flow reactor, the numerical simulation, the flow characteristics of a pump chamber.6,Conclusions1)An analysis and comparison of various valves, and finally chose the umbrella as a valve to the pump valve piezoelectric multilayer films. Pump chamber to pore fluid pressure distribution and valve position to choose theanalysis of the output to high pressure Aperture should take the flow of small value; The output for a larger flow, to increase the flow hole diameter. According to the axial fluid pressure distribution of the flow, vibration valve hole near the Vietnam film center Film vibration level of fluid force is, the better it is for the film vibration of the fluid kinetic energy into potential energy. consequently enhance the piezoelectric multilayer pump output capacity.2)Sand pads stack of piezoelectric pump to the finite element analysis, large diameter pads, the deformation vibration films will increase, This will enhance the performance of piezoelectric multilayer pump. But diameter pads not too great, because too much vibration film deformation, Vibration films will be restored to their original state in time, but it will reduce the performance of piezoelectric multilayer pump.3)With the increased input voltage, output increased with the flow and pressure, but the linear relation was not significant. With the increase in frequency of the output flow pump has been increased, the frequency is increased to around 13Hz, achieve maximum output, and with increasing frequency, the output volume will decrease. The output frequency increases pressure on the whole is increasing pressure to achieve maximum output in around 7Hz.4)Valve hysteresis of the analysis. When piezoelectric pump flow to achieve the best value, the smallest loss lag valves, and the frequency increased, the loss increased flow valves lagging sector. When the frequency of particular value, the flow is zero, the frequency will increase even reverse leakage is back. Sand stack of piezoelectric pump cavity flow field of finite element analysis. Cavity pressure of the pump is much higher than the export of imported pressure pump liquid from flowing into the entrance of the cavity, resulting in a negative pressure valve exports. Valve edge of the maximum velocity in imports and exports valve Department chaotic fluid flow direction, two in a whirlpool export dorsal valve, resulting in a partial loss of energy.
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