The Theoretical Modeling And The Static And Dynamic Characteristic Of Micropump

Today, there is growing interest in research on microfluidic systems, e.g., for chemical analysis systems and microdosage systems. One of the basic components in microfluidic systems is micropumps. During recent years several different micropumps have been presented based on different pump principles and using different actuation principles, some micropumps have come into practice.This thesis analyzed theory of micropump and built the basic equation of micropump model, solved the flux and pressure of micropump. This thesis built the model of the distortion of the electrostatic and piezoelectric micropump, resolved the inherent frequency of the circular film.In this thesis, the design of a kind of two cavities micropump was put forward. The micropump is divided into two cavities. The cavity above is composed of the wall of cavities and two layers films lies up and down, each of them has a layer of PZT chip. The cavities underside is composed of the wall of cavities, the film and a layer of class. There is circular valves lies in the import and export, and the material of the micropump films and the valves is silicon. The radius of the micropump is 3mm, the radius of the films of micropump is 2mm, the thickness of the films of the micropump is 5 m, the thickness of the PZT chip is 10 m, the tall of the micropump is 1000 m, the drive voltage is 50V, the drive frequency of the micropump is 4000Hz.This thesis built the model of micropump, the deformation of the micropump membrane and the volume change of the micropump chamber under piezoelectric-drive were simulated by finite element method (FEM). The effects of the membrane thickness, shape and piezoelectric voltage on the volume change of membrane were analyzed. The relation between intrinsic frequency and membrane thickness was also discussed. Theoutput flux of the micropump, which is 145. 5 l/min. The change of fluid velocity and pressure of the micropump was also simulated, thus we could recognize the property of the liquid of the microsystems more completely. The equivalent circuit method is a way of building micro system model. The thesis simulated the micropump system with the equivalent circuit method, worked out the change of output pressure and flux of the micropump. The sequential coupling analysis method is one of the FEM analysis method, which is suit of electrostatic-structural coupled-field analysis. The thesis applied the sequential coupling analysis method to simulate the electrostatic-drive micropump. The effects of the membrane thickness, shape and electrostatic voltage on the volume change of membrane were analyzed. The analysis results provided foundation for the structural design of the electrostatic-drive micropump and have some reference value.