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| 研究生： |
黃崢翔 Jian-Xian Huang |
|---|---|
| 論文名稱： |
封閉區間內柱狀多孔質熱源之自然對流系統 |
| 指導教授： |
林孝宗
Shaw-Chong Lin |
| 口試委員: | |
| 學位類別： |
碩士 Master |
| 系所名稱： |
工學院 - 化學工程與材料工程學系 Department of Chemical & Materials Engineering |
| 畢業學年度： | 88 |
| 語文別： | 中文 |
| 論文頁數： | 95 |
| 中文關鍵詞： | 自然對流 、多孔質 |
| 外文關鍵詞： | free convection, porous |
| 相關次數： | 點閱：18 下載：0 |
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本研究所探討的物理系統為在密閉的圓筒形空間內充滿牛頓流體，內部擺置五個排成十字形陣列的多孔質圓柱體。圓筒高度維持不變，內部的多孔質圓柱體高度與圓筒高度呈比例變化。圓筒的壁面維持等溫，而多孔質則由內部產生均勻的熱量。
在研究方法上，利用計算流體力學軟體Fluent，來求解此種特殊的自然對流系統。將所得的數值結果，以圖表的方式就系統的主要控制參數（雷立數、高度比、達西數）對流動與熱傳的影響，進行分析與探討。
本文發現當雷立數增加時，對於系統內流場與溫度場皆有較大影響力。在高雷立數時，自然對流效應增強流速變快，流體流動愈趨複雜，同時熱量由均勻向四周壁面散熱，轉變為向圓筒上方頂壁散熱。當圓筒與多孔質圓柱之高度比為4時，流體流動會由外圍向系統中心流動。當達西數增加時，雖然流場與溫度場結構會有改變，但其影響力並不如雷立數影響來的大。
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