本文目標為電液動力泵(Electrohydrodynamic Pump；EHD泵)之性能增強研究，首先對EHD泵之研究文獻進行回顧，並選定Birhane之EHD泵設計作為參考模型，藉此模型的實驗分析以了解電暈效應。經實測模型之流速曲線，結果符合文獻之反向拋物線速度分布，越接近管壁其速度越大、往管中心內速度越小。接著依據風速產生於電極之特性進行圓管式EHD泵之改良設計，對發射電極配置進行研究，其設計參數為於內圈增設發射電極(總數分別為12與16根)，及調整新增電極的徑向距離(15與20mm)；至於發射電極採用同心圓式環狀陣列，並透過性能實驗結果分析電暈物理現象。經由分析所有改良EHD泵發現，增加發射電極所提升之電場作用力，不會因電極數上升使消耗功率增加，同時觀察出增加電極數可使EHD泵之流量增加。至於電極間距部分，由實驗得知電極間距會影響離子作用力，可使體積流率進一步提升；但發射電極密度過高時，容易使電場作用彼此牽制，導致體積流率受到限制。綜合歸納本文之改良方案，皆能使EHD泵之流率提升33%、消耗功率降低35%以上；其中較佳設計之EHD泵模型2012，其體積流率提升74%、且消耗功率降低35.9%。本研究進行的設計參數實驗，除了提升EHD泵之體積流率，並且觀察電暈之物理現象，可供未來研究EHD泵或相關領域參考。

關鍵詞：電液動力泵、離子風、同心圓式配置、電極數、電極徑向距離

The aim of this experimental work was to enhance the flow-induced capability of the electrohydrodynamic (EHD) pumps, also known as EHD-driven Ironic gas pumps. Before starting the experiments, we first conducted the literature survey upon EHD research and chose Birhane’s EHD pump as reference design. The performance experiment with that design was executed and analyzed the test data to better understand the corona effect. Results showed that in a flow induced by such a pump, the velocity distribution presented an inverted parabolic trend, increasing near the pipe wall and decreasing towards the center of the tube to the lowest point. Thereafter, this research proposed a concentric-ring array of emitter electrodes for enhancing the airflow of the EHD pump. Based on the characteristics of ironic air generated around the downstream of discharge electrode, the parametric focus on improving the circle EHD pump design was mainly on discussing various placements of the emitter electrodes, such as the electrode number and the radial distance between adjacent electrode layers. The total number of emitter electrodes considered here are 12 and 16, and the radial distance of emitter electrodes are 15mm and 20mm, respectively.
Through the experiments of this concentric-ring EHD pump, it is found that increasing the amount of emitter electrodes enhances the electric field force, and therefore the EHD volumetric flow rate, without increasing the power consumption. Regarding the electrode distances, measured results showed that electrode distance affects the plasma force significantly, and can be adjusted to improve the volumetric flow rate, but if the emitter electrodes are too crowded, electric fields induced by different electrodes tend to impede each other, resulting in a reduced volumetric flow rate. In conclusion, for all the proposed concentric-ring EHD designs, this experimental investigation enlarges over 33% of volumetric flow rate and reduces over 35% of power consumption compared to the reference EHD pump. In the best model, with 12 electrodes separated by a 20mm radial distance, the enhancement on volumetric flow rate is over 74% and reduction of power consumption over 35.9 %. Consequently, this research has successfully designed a superior EHD with the concentric-ring arrangement of emitter electrodes, and executed a parametric study that not only improved the volumetric flow rate of EHD pumps, but also allowed further observation of the physical phenomena of corona effect, and can provide insights to pertinent research in the future.

Key words：electrohydrodynamic pump, corona wind, concentric-ring arrangement, discharge electrodes, radial distance

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