以電漿電弧法製造奈米流體設備之研發

Development of Nanofluid Equipment by Plasma Arc System

白峰毅(Feng-Yi Pai)

指導教授 ： 鄭慶民 ； 鄧敦平

國立臺灣師範大學/科技學院/機電科技研究所/碩士(2010年)

摘要

本研究係研發一套奈米流體製備系統，藉由過去文獻與研究的資料收集進而改良設計，從備料、加工、組銲、系統架設、實驗測試、奈米微粒分析等多個步驟組成，以氣凝合成法來製備石墨/水奈米流體（graphite/water na- nofluid），選用能量高且能對各種金屬材料加熱蒸發之電漿電弧為加熱源，將所蒸發氣化之奈米微粒收集到流體收集器中，形成石墨/水奈米流體以防奈米微粒因高溫而團簇或凝聚成較大尺寸，在實驗過程中利用參數的設計，如電流高低、流體收集器型式，試圖找出最佳製程參數，來獲得最小及均一粒徑的奈米微粒。
實驗過程分為兩階段，第一階段以固定的電流參數，測試三種不同型式之收集形態，以SEM、EDS做初步分析，判斷何種型式可得最佳奈米微粒尺度，結果得知以加裝濾網之收集形式為最佳；第二階段為設計一最佳流體收集容器，並降低其流體溫度在0至-2℃，以兩組不同電流參數配合電漿電弧銲機之脈衝(pulse)功能，將所收集之石墨/水奈米流體經超音波震盪器震盪後，再以SEM、EDS、粒徑分析儀等儀器分析，以達最佳石墨/水奈米流體製程。
經分析結果得知電流參數為70A時平均粒徑在547nm，等電點(I.E.P)為-24.4mV，電流參數為80A時平均粒徑在284nm，等電點為-21.2mV。最後對石墨/水奈米流體作熱阻試驗，發現參數80A在水溫50℃時，熱阻下降率可達20%。

關鍵字

奈米流體 ； 電漿電弧銲接 ； 石墨 ； 等電點

並列摘要

The purpose of experiment is aim to a methods of nanofluid produce system; refer to previous research data and correction. Consist with several stages: prepa- ration, modification, weld, system installation, tested; use “Evaporation synthesi- zed condensation system” to implement graphite/water nanofluid by selected hig- h energy plasma arc that can vaporize any kind of metal as a heating source, coll- ect vaporized nanoparticle into nanofluid collector. To avoid condensed bigger si- ze of particle due to high temperature or cluster, take paramenter in consideration during the period of experiment; such as working current, collector function, tryi- ng to obtain best process minimum and average nanoparticle.
By mean of two stage experiment, base on fixed current used three different type of collector to gain the proper nanoparticle by analyzing of SEM, EDS. Re- sults show the collector is better for particle collect on stage one. In order to des- ign the best collector and reduce fluid temperature from 0℃ to -2℃, within next step of experiment. Accumulate nanoparticle by different working current plasma arc torch pulse. Then stimulate with ultrasonic after that, analyze by SEM, EDS, particle size analyzer to define which process can produce perfect nanoparticle result in 70A.
As a result, working current 70A average particle is 547nm, I.E.P -24.4mV, 80A average particle is 284nm, I.E.P -21.2 mV, process graphite/water nanofluid hea ting resistance test, found that heating resistance reach to -20% under water tem- perature 50℃, paramenter 80A

並列關鍵字

Nanofluid ； Plasma Arc Welding (PAW) ； Graphite ； Iso electric point(I.E.P)

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