臺灣博碩士論文加值系統

　　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.

摘 要 I
Abstract III
致 謝 V
目 錄 VI
圖索引 X
表索引 XIII
第一章 緒論 1
1.1 前言 1
1.2 文獻回顧 6
1.2.1電液動泵之電極設置、放電特性 6
1.2.2電液動泵在不同級數與電極配置之性能研究 8
1.3研究動機與方法 12
第二章 原理介紹 15
2.1 EHD概論 15
2.2 電暈現象 21
2.3 物理系統之統御方程式 26
2.3.1流場統御方程式 27
2.3.2電磁統御方程式 28
2.3.3 EHD泵之驅動力 32
2.4 EHD之性能評估參數 34
第三章 EHD泵實驗設備與方法 36
3.1 實驗設備與儀器 36
3.2 實驗平台與量測流程 48
3.2.1 實驗平台建立 48
3.2.2 實驗流程 50
第四章單級相鄰雙面EHD泵之性能分析 56
4.1 單級EHD泵之參考模型 56
4.2 單級相鄰方管EHD泵之模型量測方法 69
4.2.1 單級相鄰型方管模型 69
4.2.2 量測點速度之對稱性 71
4.3 單級相鄰型方管EHD泵之性能 74
4.3.1 單根放電電極模組 74
4.3.2 三根放電電極模組 83
4.3.3 七根放電電極模組 85
4.3.4小結 87
4.4 單級參考模型與相鄰雙面之單級EHD泵之性能比較 88
第五章 雙級相鄰EHD泵之模型設計與分析 91
5.1雙級雙面的EHD泵之模型說明 91
5.1.1 雙級平行雙面EHD泵之參考模型 91
5.1.2雙級相鄰雙面的EHD泵 94
5.2 相鄰雙面之雙級同面式方管EHD泵的量測性能討論 97
5.2.1 單根放電電極 98
5.2.2 三根放電電極 101
5.2.3 七根放電電極 102
5.2.4 小結 109
5.3相鄰雙面之雙級交錯180˚式方管EHD泵的量測性能討論 110
5.3.1 單根放電電極 110
5.3.2 三根放電電極 114
5.3.3 七根放電電極 118
5.3.4 小結 122
5.4相鄰雙面之雙級交錯270˚式方管EHD泵的量測結果討論 123
5.4.1 單根放電電極 123
5.4.2 三根放電電極 126
5.4.3 七根放電電極 130
5.4.4 小結 133
5.5 相鄰雙面之雙級EHD泵與參考模型比較 133
5.5.1不同上下級搭配的相鄰雙面之EHD模型比較 134
5.5.2 相鄰雙面型與參考模型的雙級EHD泵之性能比較 135
第六章 結論與建議 147
6.1 結論 147
6.2 建議 149
參考文獻 151

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