壓電式微型幫浦之數值模擬

Abstract

微流體系統中通常包含了微流道、微型閥、微感測器以及微致動器等元件，可視不同應用領域設計加裝其它元件，做廣泛之應用。本文探討之微流體系統中使用壓電式微型幫浦作為微致動器，其可區分為閥式與無閥式微幫浦。本研究係以計算流體力學套裝軟體，分析閥式與無閥式之壓電幫浦，目的在研析出具有高流量且體積小的微型幫浦。 本文於模擬進行前，針對計算軟體進行動態網格之驗證，並模擬參考文獻中漸擴/漸縮管式之無閥式微幫浦，以暸解計算結果之準確性。文中探討特斯拉閥有助於無閥幫浦之流量表現、閥式幫浦中PDMS閥體之擺動受致動器振動頻率的影響，並設計性能參數比較幫浦性能。 本研究使用單邊擺動之壓電片製作閥式幫浦，於工作頻率為140 Hz下實驗得到120 ml/min的流量表現。文中建立之微型幫浦相關模擬，可作為未來改進幫浦表現之輔助分析方法。

A micro-fluid system usually involves Micro Channel、Micro Valve、Micro Sensor and Micro Actuator. Moreover, micro-fluid systems may be applied in different areas after installing other units with proper designs. This study integrates and classifies the micropump into “Valve-less micro-pump” and “Valve micro-pump”, and uses CFD based computer simulations. The main idea is to develop a smaller size micro-pump with high flow rate. This study brings up new ideas of modified valve-less micro-pump, and a valve micro-pump with “one-side actuating” piezoelectric ceramic and PDMS valves. At the first part of this study, the simulations of the related references are to verify the moving grid in the CFD software and the accuracy between the simulation and experiment results. The valve-less micropump may improve the pump flow rate with a Tesla valve, and the interaction between working frequency and the valve movement in the valve micropump are discussed. And the pump rate of valve micro-pump can reach 120ml/min with the pump diaphragm vibration frequency set to 140 Hz. The developed simulation model can be used as the tool for analyzing and improving pump performance in the future.