本研究搭配實驗室研究團隊所設計的單邊擺動壓電式薄膜泵,設計一流量感測器,藉由調整壓電片驅動頻率改變驅動流量大小,再以流量感測器感測不同流量的變化。流量感測器流道採用鋁材質加工而成,整體尺寸為80 mm × 30 mm × 20 mm,採用加熱片作為加熱元件,利用工作流體將熱帶走,在固定加熱功率下,利用流量和加熱元件表面溫度之間的關係作為感測流量之方式。本實驗採用的薄膜泵設計,經實驗後的結果,得到在150 Hz時,有最大流量1.13 mL/s,最大揚程為1366.0 Pa,而感測器的實驗結果顯示感測器的效能會受加熱功率大小以及流量大小影響,在功率大以及流量小的時候感測器的靈敏度有比較好的表現;另外對於感測器流道的懸臂式設計做了實驗驗證,採用懸臂式設計能夠增進隔熱效果,有助於改善感測器之效能。
In this study, a new flow sensor combined with the valveless one-side actuating piezoelectric micropump has been successfully developed. The dimension of the flow sensor is 80 mm × 30 mm × 20 mm. The flow sensor uses a silicone heater that is fixed on the top of the microchannel and dissipates the heat by the flow inside the channel. Under constant heating power, we can obtain the relationship between the surface temperature of the heater and the flow rate and use it to measure the flow rate. The maximum flow rate of the valveless micropump is 1.13 mL/s at 150 Hz; while the maximum pump head can reach 1366.0 Pa. The experimental results indicate that the performance of the flow sensor is dominated by the heating power and the flow rate, and the performance is enhanced with increasing the heating power or decreasing the flow rate. Besides, the design of the microchannel suspended from the substrate to improve thermal isolation also proves better performance.