降低氣泡於微型壓電式幫浦影響之創新腔體設計研究

Abstract

本研究針對氣泡對於微型壓電式幫浦的影響做了詳盡的探討，並提出了一款新型的腔體設計以減少氣泡對於微型壓電式幫浦的影響。以壓電片作為此微型幫浦之致動元件，並以懸臂梁式閥作為腔體進出口處的控制元件。 為了找到此幫浦的最佳腔體深度，分別以六款不同深度的腔體於不同的致動器操作頻率下進行幫浦流量、自吸能力與氣泡忍受力的探討。在腔體深度為1.0mm與35Hz下，幫浦擁有最大的流量302.1ml/min；腔體深度為1.0mm與15Hz下有最短的自吸時間14s；並在15Hz與70Hz時擁有無限大的氣泡忍受力。此外，為探討氣泡對於此微型壓電式幫浦的影響，分別對此六款不同深度的腔體在不同致動器操作頻率下，打入不同體積的氣泡進行幫浦流量測試。 新型腔體利用氣泡選擇處於較低表面位能的原理，使得氣泡與水達到流道分離的效果，以避免氣泡對水的干擾。針對新型腔體重複上述測試並比較其與平面型腔體的差異，結果顯示新型腔體在相同的幫浦流量與自吸能力下，氣泡對於新型腔體之流量的影響明顯下降外，也擁有較高的流量穩定性，且新型腔體更是提升了大約100%的氣泡忍受力。

This study makes a deep research into the impact of bubble on a bridge-type- check-valves piezoelectric micro-pump and develops an innovative chamber design to enhance its performance against bubble. To find the optimum depth of chamber, the pumping flow-rate, self-priming ability and bubble tolerance at different actuating frequency are tested for six different depth of chambers. The results show that the micro-pump has a maximum flow-rate of 302.1ml/min at 35Hz and a shortest self-priming time at 15Hz with 1.0mm depth of chamber. An infinite bubble tolerance can also be found at both 15Hz and 70Hz. Besides, in order to have a complete understanding of the bubble impact on this kind of pump, different volume of bubbles are injected into the six different depth of chambers to test the flow-rates at different frequency. Based on the principle of that bubble chooses to be in a lower surface-energy state, this innovative chamber design can separate the bubble’s channel from water’s one and avoid bubble influence on the flow of water in the micro-pump. After repeating the above test on the new chamber and comparing with the traditional plane chamber; the impact of bubble on the flow-rate is much reduced and the stability of the micro-pump is enhanced at the same flow-rate and self-priming time too. And, the bubble tolerance of this new kind of chamber is 100% more than the traditional one.