本研究旨在設計與製造平板型微擴流器閥在非穩態流場下之整流效率測試平台，流體之驅動係使用陶瓷壓電致動器與PDMS薄膜的結合，並利用CCD雷射位移感測器來量測薄膜的位移，繼而得知致動腔體之體積變化量，另ㄧ方面在擴流器出口處量測淨流量。所量測之結果可用以計算微擴流器閥之整流效率。本研究針對頸部寬度為200μm，長度為3000μm，深度約為200μm，擴張角為10°~40°之平板型微擴流器，工作流體為甲醇，致動頻率範圍為2~100Hz，所對應之羅緒科數（Roshko number）為0.11~5.71進行量測。量測結果發現，四種角度的微擴流器閥都具有正向整流效率。其中當微擴流器之擴張角為100，羅緒科數（Roshko number）為2.29時，整流效率最佳，約為23.25%。

The purpose of the present study is to design and fabricate the test platform used for measuring the rectification efficiency of planar micro-diffuser valves under an unsteady flow field. The fluid is pumped and filmed with a stacked-type PZT. The displacement of the actuator is measured by a CCD laser displacement sensor so that volumetric variation of the chamber can be obtained. The net volumetric flow rate of the diffuser valve is also measured and used to calculated the rectification efficiency of the diffuser valve. The diffusers are designed with a throat width of 200μm and four different diverging angle of 10°~40°. The length and the depth of the diffuser are 3000μm and 200 μm, respectively. Methanol is used as the test fluid. The actuation frequency is ranged between 2 and 100 Hz resulting in the Roshko number between 0.11~5.71. Experimental results show that all the tested diffusers have positive rectification efficiency. The maximum rectification efficiency about 23.25% occurs at 10°-diffuser operating at the Roshko number of 2.29.

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