臺灣博碩士論文加值系統

在污染日益嚴重的今天，環保議題已不再單是政府的責任了，而是你我應重視的問題；然而在航運快速的發展之下，海洋環境的保護已不容許漠視了。如何處理船舶所產生的廢油污水，為目前最緊迫且最重要的課題之一，本研究便是以裝設於船舶上之旋流式油水分離器做為探討的對象。並借助計算流體力學套裝軟體的數值模擬，有效的分析其物理現象。
本研究使用套裝軟體Fluent進行旋流器內部流場之分析，並使用雷諾應力模式(Reynolds Stress Model , RSM)及多相流模式(Multiphase Flow Model)，針對不同外型之旋流器進行討論，以找出最佳化之尺寸關係。吾人由結果得知，在增加圓錐段與圓筒段長度比值時，隨著其比值增加，圓錐段漸縮腔增長，軸向及切線速度隨之上升，而此時旋流器內具有交錯排列的渦流，其上下分流區域延後接近底流口處發生，因此其分離效率隨之上升。另在增加溢流口與底流口直徑比值時，隨著直徑比值增加，底流口直徑減小，軸向及切線速度上升，上下分流區域亦延後接近底流口處發生，分離效率也隨之上升，而此時接近底流口處具有較多交錯排列的小渦流，有助於將油份帶往溢流口排出。

Today, pollution is serious day by day, the environmental protection topic has already no longer been the government's responsibility only, but the question which you and I should pay attention to; But under the fast development of shipping, the protection of the marine environment has not been permitted to ignore yet. To deal with the oily water that produced by shipping is the most urgent and most important subjects at present. To setup a hydrocyclone on the ship was one of the popular oil water separator devices in recent years, this study utilize existing CFD software to simulate the separating efficiency of the hydrocyclone with different parameters, and can effective analysis its physical phenomenon.
This research mainly utilized Fluent software to analyze the flow fields within the hydrocyclone, including the Reynolds Stress Model(RSM), and Multiphase Flow Model. Different geometric types and sizes are analyzed and studies, the numerical result show that increasing the length of the conical part (HCN), the axial and tangential velocity decreasing with it, and the separating efficiency also decreasing with it. When we increasing the diameter ratio of the underflow and overflow, the velocity field and the separating efficiency decreasing with it.

中文摘要...................................................i
Abstract................................................. ii
目錄.....................................................iii
表目錄.....................................................v
圖目錄....................................................vi
符號說明................................................viii

第一章 緒論...............................................1
1-1 前言................................................1
1-2 文獻回顧............................................2
1-3 研究目的............................................4
第二章 數學統御方程式及物理模型...........................6
2-1 基本假設............................................6
2-2 統御方程式..........................................6
2-3 紊流介紹............................................7
2-4 物理模型及邊界條件..................................8
2-4-1 物理模型........................................8
2-4-2 邊界條件........................................9
第三章 數值方法..........................................10
3-1 FLUENT介紹.........................................10
3-1-1 RSM紊流模式....................................11
3-1-2 混合多相流模式.................................12
3-2 格點系統...........................................15
3-3 離散化方法.........................................15
3-4 求解程序...........................................17
第四章 結果與討論........................................20
4-1 格點系統及文獻驗證.................................20
4-2 流場軸向及切線速度之計算結果.......................21
4-2-1 Do/Du=4.7時，Hcn/Hcl對軸向及切線速度之影........21
4-2-2 Do/Du=2.0時，Hcn/Hcl對軸向及切線速度之影響......22
4-2-3 Do/Du =1.52時，Hcn/Hcl對軸向及切線速度之影響....22
4-2-4 Hcn/Hcl=16.5時，Do/Du對軸向及切線速度之影響.....22
4-2-5 Hcn/Hcl=9時，Do/Du對軸向及切線速度之影響........23
4-2-6 Hcn/Hcl=4時，Do/Du對軸向及切線速度之影響........23
4-2-7 Hcn/Hcl=1時，Do/Du對軸向及切線速度之影響........24
4-3 流場流跡線之計算結果...............................24
4-3-1 Do/Du固定時，比較不同Hcn/Hcl對流場之影響........24
4-3-2 Hcn/Hcl固定時，比較不同Do/Du 對流場之影響.......25
4-4 混合模式分離效率計算結果...........................25
4-4-1 無因次體積分率等值比較圖.......................25
4-5 量化比較油水分離器之分離效率.......................26
4-5-1 油水濃度與圓錐圓筒長度比值(Hcn/Hcl)之關係......26
4-5-2 油水濃度與溢流口底流口直徑比(Do/Du)之關係......27
第五章 結論與未來展望....................................28
5-1 結論...............................................28
5-2 未來展望...........................................29
參考文獻..................................................30
附表......................................................32
附圖......................................................33

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