本研究設計製作一個測試圓錐型擴流器閥之性能的平台，在致動腔兩側安裝擴流器元件，擴流器閥之頸部直徑為2.5mm，使用水為工作流體，細長比為7.5，擴張角範圍 ~ ，直流馬達驅動的活塞為致動器，致動頻率在4Hz ~ 50Hz之間，這些參數所對應的羅緒科數範圍為25 ~ 300。
實驗結果顯示，整流效率隨Ro數增加而增加，達到一個最佳值後，再增加Ro數則會使整流效率下降。小角度( )的圓錐型擴流器閥在羅緒科數為204時具有最佳的整流效率49%，遠優於大角度之擴流器閥。使用衝程較小之偏心輪，活塞驅動流體較少，但卻得到較好的整流效率。泵腔內動態壓力訊號在不同頻率下具有不同特徵，此壓力訊號之平均值可用以計算在淨流量為零但背壓差最大之條件下，擴流器閥之性能，其結果與淨流量最大但背壓差為零時直接量測之整流效率相互呼應。

This study is to build up a platform for testing the performance of conical diffuser valves. This test platform consists of two identical diffuser elements on each side of an actuation chamber. The volume of the chamber varies periodically due to the oscillating motion of a piston driven by a DC motor and an eccentric disk. The actuation frequency is in the range of 4 Hz to 50 Hz. Water is selected as working fluid. The diffuser valves have throat diameter of 2.5 mm, a slenderness of 7.5, and a range of diverging angles of 10° - 35°. These parameters result in Roshko numbers varying between 25 and 300.
Experimental results show that the rectification efficiency of the conical diffusers increase with increasing Roshko number, reaches a maximum, and then decreases thereafter. Small angle diffusers exhibit a much better rectification efficiency than the diffusers with large diverging angles. An optimal efficiency of 49% is obtained for the 10°-diffuser at the Roshko number of 204. In order to quantify the performance of the diffuser valves, dynamic pressure in the actuation chamber is also measured and used to calculate the diffuser efficiency under the condition of maximum back pressure. Consistent results are obtained with the direct measurements of the rectification efficiency of the diffuser valves under zero load condition.

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