簡易檢索 / 詳目顯示

研究生: 賴盈宏
論文名稱: 微氣泡於垂直圓管內浮升之形狀變化研究
指導教授: 李雄略
口試委員:
學位類別: 碩士
Master
系所名稱: 工學院 - 動力機械工程學系
Department of Power Mechanical Engineering
論文出版年: 2007
畢業學年度: 95
語文別: 中文
中文關鍵詞: 曲率氣泡形狀流場
相關次數: 點閱:2下載:0
分享至:
查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報
  • 由於微小氣泡生成的問題以及在微流道中流動的情形,在微機電系統中應用層面相當廣泛,深具發展潛力,且在微尺度的狀況下,使用實驗觀察並不容易,所以數值模擬方法越顯重要性,若兩者能互相印證,則可以更加了解此氣泡所代表的物理行為。
    本文的目的是以數值方法研究單一氣泡在圓柱容器中上升時所產生的周圍流場,將流場所引發的曲率反求出氣泡變形的形狀,以及氣泡上升的終端速度。
    本研究發現當流場穩定之後,自由液面的壓力差會影響氣泡曲率,不同的曲率得到不同的氣泡半徑,將曲率反求出氣泡形狀,觀察氣泡的變形,可發現變形量很小,且氣泡形狀為上下不對稱且近似橢圓形;由於曲率是二次微分的函數,如果以現有形狀求曲率,會導入過多雜訊與誤差而無法求解,本文提出一個方向,由曲率反求形狀,以解決這問題。


    目錄 摘要 Ⅰ 致謝 Ⅱ 目錄 Ⅲ 圖目錄 Ⅴ 符號說明 Ⅵ 第一章 緒論 1 1.1前言 1 1.2文獻回顧 1 1.3目的 5 第二章 理論分析 6 2.1問題描述 6 2.2統御方程式 7 2.3自由液面法線速度 10 2.4曲率反求形狀 11 2.5氣泡體積 13 2.6邊界條件 14 第三章 數值方法 15 3.1統御方程式之差分-單相區 16 3.2統御方程式之差分-跨相區 18 3.3利用NAPPLE求解壓力場 19 3.4利用NAPPLE求解中心線壓力場 23 3.5計算流程 26 第四章 結果與討論 27 4.1網格系統與模擬參數 27 4.2收斂曲線、流場與壓力場 28 4.3曲率的比較 30 4.4氣泡形狀的比較 31 4.5終端速度與氣泡大小的關係 32 第五章 結論 34 參考文獻 35

    參考文獻
    [1] Duineveld, P. C., 1995, “The rise velocity and shape of bubbles in pure water at high Reynolds number,” Journal of Fluid Mech., Vol. 292, pp. 325-332.
    [2] Wu, M., Gharib, M., 2002, “Experimental studies on the shape and path of small air bubbles rising in clean water,” Physics of Fluids,Vol. 14, pp. L49-L52.
    [3] I, Zun., 1980, “The transverse migration of bubbles influenced by wall in vertical bubbly flow,” Int. J. Multiphase Flow., Vol. 6, pp. 583-588.
    [4] Takemura, F., Takagi, S., Magnaudet, J., et al., 2002, “Drag and lift forces on a bubble rising near a vertical wall in a viscous liquid,” J. Fluid Mech.,Vol. 461, pp. 277-300.
    [5] Krishna, R., Urseanu, M.I., van Baten, J.M., Ellenberger, 1999, “Wall effects on the rise of single gas bubbles in liquids,” Int. Comm. Heat Mass Transfer, Vol. 26, pp. 781-790.
    [6] M. de Tezanos Pinto., M. A. Abraham., R. L. Cerro., 1997, “How do bubbles enter a capillary” Chemical Engineering Science, Vol. 52, No. 11, pp. 1685-1700.
    [7] Ortiz-Villafuerte, J., Hassan, Y.A., Schmidl, W. D., 2001, “Rocking motion, trajectory and shape of bubbles rising in small diameter pipes,”Experimental Thermal and Fluid Science, 25, pp. 43-53.
    [8] Hirt, C. W., Nichols, B. D., 1981, “Volume of Fluid (VOF) Method for the Dynamics of free Boundaries,” Journal of Computational Physics, Vol. 39, pp. 201-225.
    [9] Shirani, E., Ashgriz, N., Mostaghimi, J., 2005,“Interface pressure calculation based on conservation of momentum for front capturing methods” Journal of Computational Physics, Vol. 203, pp. 154-175.
    [10] Lee, S. L., and Sheu, S.R., 2001, “A new numerical formulation for incompressible viscous free surface flow without smearing the free surface,”International Journal of Heat and Mass Transfer, 44, pp. 1831-1848.
    [11] 張元榕, “微氣泡於垂直方管內上升之研究”,國立清華大學碩士論文,2005
    [12] Moore, D. W., 1963, “The Boundary Layer on a Spherical Gas Bubble,” Journal of Fluid Mechanics, Vol. 16, pp. 161-176.
    [13] Magnaudet, J.,Rivero, M. and Fabre, J., 1995,“Accelerated flows past a rigid sphere or a spherical bubble. Part 1. Steady straining flow,”Journal of Fluid Mechanics, Vol. 284, pp. 97-135.
    [14] Sarpkaya, T., 1996, “Vorticity, free surface and surfactants,” Annual Review of Fluid Mechanics,Vol. 28, pp. 83-128.

    [15] Tsai, W. T., and Yue, D. K. P., 1996, “Computation of nonlinear free-surface flows,”Annual Review of Fluid Mechanics,Vol.28, pp. 249-278.
    [16] Lee, S. L., 1989, “Weighting function scheme and its application on multidimensional conservation,” International Journal of Heat and Mass Transfer, Vol.32, pp. 2065-2073.
    [17] Lee, S. L., and Tzong, R. Y., 1991, “An Enthalpy Formulation for Phase Change Problems,” Int. J. Heat Mass Transfer, Vol.34, pp. 1491-1502.
    [18] Lee, S. L., and Tzong, R. Y., 1992, “Artificial pressure for pressure-linked equation,” International Journal of Heat and Mass Transfer, Vol.35, pp. 2705-2716.
    [19] Lee, S. L., 1989, “A strongly-implicit solver for two-dimensional elliptic differential equations,” Numerical Heat Transfer,Vol.16, pp. 161-178.
    [20] White, Frank M., 1991, “Viscous Fluid Flow”, 2nd ed., McGraw-Hill, New York, pp. 183-184.
    [21] 王信雄, “微小氣泡於軸對稱圓管內上升運動之研究”,國立清華大學碩士論文,2006

    無法下載圖示 全文公開日期 本全文未授權公開 (校內網路)
    全文公開日期 本全文未授權公開 (校外網路)

    QR CODE