本研究相鄰雙面之探討單/雙級EHD泵方管模型，在不同電極根數與配置，測試統整其流量、效率、與流場型態以找出最佳化EHD泵模型。電極排列方式皆為相鄰雙面電極配置，相鄰雙面之雙級配置包括同面式、交錯180˚與交錯270˚三組，而探討參數為1根、3根、7根電極模組，對應電極間距分別為2、1與0.5英吋；利用熱線式風速計量測找出其風速分布，再與參考模型單面、平行雙面電極配置做比較。彙整其實驗結果發現，提高電壓使電場作用力提升，進而使衍生之電暈風速及流量提高，但是所能提升之流量將漸趨平緩，故效率因子之趨勢會與流量相反。至於在速度場分佈，電極所產生電暈風較高風速主要集中在電極下方，越遠離電極風速呈遞減；在EHD性能比較上，單級相鄰雙面最佳化模型為配置三根電極，量測到最佳流量(電壓26kV)與最佳效率(電壓24kV)，分別為11.63CFM與25.36CFM/W，與單級參考模型相比(三根電極)發現，流量最大為相鄰雙面模型11.63 CFM，其次平行雙面模型9.73 CFM、而最差為單面模型7.55 CFM。
雙級之相鄰雙面最佳化模型配置上，選用上下級電壓皆為26kV或24kV作其性能比較，在雙級同面式模型配置也以三根電極，能產生最佳流量14.76CFM與最佳效率14.42CFM/W；而雙級交錯180˚EHD泵模型以電極三根可產生最佳流量16.70CFM，且1根電極的23.11CFM/W有最佳效率；至於雙級交錯270˚EHD泵模型以3根電極16.25CFM為最佳流量，在效率比較上以1根電極的21.31CFM/W最佳。與雙級參考模型流量相比(三根電極)，同面式模型以平行雙面模型能產生最大流量17.82CFM，次佳為相鄰雙面模型14.76CFM，流量最低為單面模型8.55CFM；另外在兩級交錯180˚的相鄰雙面模型能產生最大流量16.70CFM，次佳為平行雙面模型14.57CFM，而流量最低為單面模型9.21CFM。
　　至於在速度場部分，單根電極所產生之電暈風主要集中在電極下方，越遠離電極下方風速逐漸下降；而三根電極風速分布在相鄰雙面電極交接處風速有提高的趨勢，平均風速較七根電極高，而七根電極風速較平穩，但平均風速較低。雙級電極同面配置使上級氣流得以延續，下級風速會有明顯加成效果；交錯180˚模型會使低風速區域風速提升使流量提升，而交錯270˚模型則是綜合前二者優點，雙級模型一側上下皆有電極時，會使風速有明顯加速效果，而在雙級有電極的其他兩側會使風速提高，故其氣流混合均勻之效果最佳。

This experimental research examines the one/two stage electrohydrodynamic (EHD) gas pump inside a square channel with electrodes flush mounted on two neighboring walls at each stage. The two-stage electrode modules considered here include in alignment, offset, and 90˚-rotation arrangements for studying the flow pattern, discharge flow rate, and energy efficiency factor, which is defined as the volume flow rate delivered by a unit power input. Besides, three electrode assemblies (separately with 1, 3 and 7 electrodes in each wall) are investigated for their effectiveness in enhancing the volume flow rate as well as reducing the power requirement. In general, the measured results indicate that ion wind velocity and flowrate increase as the operating voltage increases; however, the less growth rates on velocity and flowrate are induced by a higher voltage. Also, the small electrode distance within the 7-electrode module results in the electric-field interference and reduction on the discharge airflow. As for the velocity pattern, the ion wind generated by the single electrode is concentrated directly below the emitting electrode. Also, the velocity distribution produced by multiple electrodes are relatively uniform, which is favorable to promote flow mixing inside the channel. Regarding the one-stage EHD, performance of this two-neighboring-wall EHD is superior to that of the two-parallel-wall EHD. This EHD with 3-elctrode module can generate the highest flowrate 11.63 CFM at 26KV and the maximum efficiency factor 25.36 CFM/W at 24KV.
In the two-stage EHD, the maximum flowrate (16.7 CFM) is recorded in the offset two-stage arrangement of three-electrode module at 26KV while the in-alignment and 90˚-rotation arrangements deliver 16.25 and 14.76 CFM, respectively. Regarding the energy efficiency factor, the 1-electrode 2-stage EHDs operate at 24KV generate the maximum efficiency factors 23.11, 21.3, and 13.56 CFM/W for the aligned, the 90˚-rotation, and the offset two-stage arrangements, respectively. Besides, the exit flow patterns at the 2nd stage are observed for checking the swirling and mixing effects of all two-stage arrangements. Clearly, the in-alignment two stages can continue the Corona wind to downstream and enhance the flowrate significantly. The offset arrangement can enlarge the flowrate via improving the low-speed problem near two walls without electrodes in the in-alignment two-stage EHD. Furthermore, the 90˚-rotation arrangement owns both advantages of the previous two-stage arrangements and is the best swirling flow generator among all the two-stage EHD gas pumps considered in this study.

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