Simulation and optimization of dynamic passive valve micropump

Abstract

Dynamic passive valve micropump is a kind of PZT actuation, valveless micropump which has higher working frequency, high reliability, simple structure, low cost. It can easily match many kinds of requirement in application. Some micropumps have been fabricated in our laboratory. The performance of dynamic passive valve micropump is in close relationship with structural parameters such as diffuser's aperture angle, diffuser's channel length, diffuser's channel smallest cross-section diameter. At the same time, its performance also depends on the fluid' s Reynolds number and the working frequency of PZT actuation as well. In this paper, firstly we give the relationship between the performance of the micropump and these parameters. Then we build a micro hydrodynamic model of micro pump by the finite element method. In this model, we take the coupling of fluid in micro chamber and two micro valves into consideration. The restriction of micro fabrication is also considered. By simulation and computation, we obtained the fluid status such as laminar flow, turbulent flow. We also get the fluid motion status such velocity of flow, the direction of the current. By some calculation, we gain the flux of micropump. Based on these results, one optimization design of micropump is attained. And according to this design, we fabricated and assembled some samples of dynamic passive micropump.