关键词: 微泵, 压电薄膜, 超声行波, 微流体

Abstract:

A novel type of valveless mechanical micro-pump was proposed herein.It transported the liquid depending on the driving force of traveling wave which was produced by piezoelectric films fabricated on the top surface of the channel.Using finite element software,according to the principle of ultrasonic traveling wave driving,a model was structured and solved.The relationships among the velocity of microfluidic and driving factors such as the dynamic viscosity of liquid,the driving voltage amplitude and frequency were obtained for the first time under condition of the selected modal of square micro-pipe with a caliber of 200μm.The results show that the voltage amplitude is proportional to the flow velocity and the best driving efficiency is obtained on the resonance frequency;When the dynamic viscosity is below 0.001Pa·s, the flow velocity will increase along with the rising viscosity while decrease above that value.In addition,the section velocity vector diagrams have been obtained,which illustrate that the flow velocity,under a remarkable traveling wave driving force,decreases in the microchannel from ceiling to bottom gradually.On the contrary,it's  nearly a parabolic shape where the traveling wave driving force is extremely faint. 

Key words: micropump, piezoelectric film, ultrasonic traveling wave, microfluidic