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研究生:陳意欣
研究生(外文):Yi-Shin Chen
論文名稱:三角形封閉盒內之熱質自然對流研究
論文名稱(外文):NATURAL CONVECTION HEAT AND MASS TRANSFER IN A TRIANGULAR ENCLOSURE
指導教授:王立文王立文引用關係
指導教授(外文):Lin-Wen Wang
學位類別:碩士
校院名稱:元智大學
系所名稱:機械工程學系
學門:工程學門
學類:機械工程學類
論文種類:學術論文
論文出版年:2009
畢業學年度:97
語文別:中文
論文頁數:205
中文關鍵詞:三角形封閉盒熱質傳自然對流
外文關鍵詞:triangular enclosureheat and mass transfernatural convection
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本研究是藉由實驗方式來探討一三角形封閉盒內之熱質自然對流現象。此熱質自然對流現象主要是由於溫度梯度及濃度梯度所引起,再加上幾何形狀為一等腰直角三角形的設計與邊界條件,徹底探討熱質自然對流在其間的變化。
本次實驗中,等腰直角三角形的任兩邊由銅組成,第三邊則為壓克力(視為絕緣、絕熱),實驗的工作流體為0.05M的硫酸銅水溶液(CuSO4+H2SO4+H2O)。溫度梯度由兩個不同溫度的恆溫水槽來維持,濃度梯度則是以電化學系統來建立。流場的觀察是採以雷射光暗影法後,再以數位相機拍照紀錄。
為了解流場之結構,本研究對流場的溫度及濃度分布做測量,最後再針對質傳遞率Sh值與Grm、Grt之間關係做分析。在固定Grm的情況下,Sh值會隨著Grt的增加而呈現遞增狀態。
最後得到的結論有:當在熱質逆向的cases中,會有鹽手指的產生;此外,在熱質順向的cases中,熱源在冷源上方,此時可觀察到多重渦流的流場型態。在質傳遞率Sh值與Grm、Grt之間關係探討中,實驗得出,當Grt增加Sh值也隨之增加;另外,在熱質順向時的質傳遞率較逆向來得要好。
本實驗中無因次參數研究範圍如下:
Pr=7~8,Sc=1700~2100,Grt =8.75×106,Grm=9.35×107,|N|= 10.69
The current study is primarily motivated to gain a better understanding of the flow pattern, the temperature and concentration gradient cause by thermosolutal convection in an electrochemical system with a right triangular enclosure.
The test cell is a right triangular enclosure formed with acrylic, Bakelite and copper plates, which is wrapped with block Bakelite insulator to ensure an adiabatic boundary condition.
In this experiment, the temperature and the concentration differences are made between two copper walls. The research area targets the flow pattern, change of Grt. We use copper sulphate-sulfuric acid solution as the working fluid. Two constant temperature baths sustain the temperature gradient. The concentration gradient is controlled via an electrochemical system. In order to visualize the flow, the shadowgraph technique is used.
To understand the flow structure, the temperature distribution and concentration distribution will be investigated. Finally, the correlations between the Sherwood number, and the thermal Grashof number will also need to be analyzed.
It is demonstrated that multilayer structure and finger type flow are found in the cooperating case and the opposing case, respectively. It is also found that Sh increased with increasing Grt for fixed Grm value and decreased with increasing θ(inclination angle).
The ranges of the parameters in this study are:
Pr=7~8,Sc=1700~2100,Grt =8.75×106,Grm=9.35×107,|N|= 10.69
封面 1
書名頁 2
中文摘要 3
英文摘要 4
誌謝辭 5
目錄 6
圖表目錄 12
符號說明 16
一、 前言 17
二、 實驗設計與方法 19
2.1. 溫度梯度的建立 19
2.2. 濃度梯度的建立 19
2.3. 實驗裝置 20
2.4. 實驗過程 21
2.5. 流場觀察 22
2.5.1. 雷射光暗影法 22
2.5.2. 溫度的量測 22
2.5.3. 濃度的量測 22
三、 實驗結果與討論 24
3.1. 流場整體結構 24
3.2. 雷射光暗影法之流場型態分析 25
3.2.1側板加熱斜板冷卻. 25
(1) Case1-1 順向流場 25
(2) Case1-2 逆向流場 25
3.2.2側板冷卻斜板加熱. 26
(1) Case1-3 順向流場 26
(2) Case1-4 逆向流場 26
3.2.3側板冷卻下板加熱. 27
(1) Case2-1順向流場 27
(2) Case2-2逆向流場 27
3.2.4側板加熱下板冷卻. 27
(1) Case2-3順向流場 27
(2) Case2-4逆向流場 28
3.2.5斜板加熱下板冷卻. 28
(1) Case3-1順向流場 28
(2) Case3-2逆向流場 29
3.2.6斜板冷卻下板加熱. 29
(1) Case3-3順向流場 29
(2) Case3-4逆向流場 29
3.2.7左板加熱下板冷卻. 30
(1) Case4-1順向流場 30
(2) Case4-2逆向流場 30
3.2.8右板冷卻下板加熱. 30
(1) Case5-1順向流場 30
(2) Case5-2逆向流場 31
3.2.9左板加熱右板冷卻. 31
(1) Case6-1順向流場 31
(2) Case6-2逆向流場 32
3.3. 流場溫度分布 32
3.3.1側板加熱斜板冷卻. 32
(1) Case1-1 順向流場 32
(2) Case1-2 逆向流場 32
3.3.2側板冷卻斜板加熱. 33
(1) Case1-3 順向流場 33
(2) Case1-4 逆向流場 33
3.3.3側板冷卻下板加熱. 33
(1) Case2-1順向流場 33
(2) Case2-2逆向流場 34
3.3.4側板加熱下板冷卻. 34
(1) Case2-3順向流場 34
(2) Case2-4逆向流場 34
3.3.5斜板加熱下板冷卻. 34
(1) Case3-1順向流場 34
(2) Case3-2逆向流場 35
3.3.6斜板冷卻下板加熱. 35
(1) Case3-3順向流場 35
(2) Case3-4逆向流場 35
3.3.7左板加熱下板冷卻. 36
(1) Case4-1順向流場 36
(2) Case4-2逆向流場 36
3.3.8右板冷卻下板加熱. 36
(1) Case5-1順向流場 36
(2) Case5-2逆向流場 36
3.3.9左板加熱右板冷卻. 37
(1) Case6-1順向流場 37
(2) Case6-2逆向流場 37
3.4. 流場濃度分布 37
3.4.1側板加熱斜板冷卻. 37
(1) Case1-1 順向流場 37
(2) Case1-2 逆向流場 38
3.4.2側板冷卻斜板加熱. 38
(1) Case1-3 順向流場 38
(2) Case1-4 逆向流場 38
3.4.3側板冷卻下板加熱. 38
(1) Case2-1順向流場 38
(2) Case2-2逆向流場 39
3.4.4側板加熱下板冷卻. 39
(1) Case2-3順向流場 39
(2) Case2-4逆向流場 39
3.4.5斜板加熱下板冷卻. 40
(1) Case3-1順向流場 40
(2) Case3-2逆向流場 40
3.4.6斜板冷卻下板加熱. 40
(1) Case3-3順向流場 40
(2) Case3-4逆向流場 40
3.4.7左板加熱下板冷卻. 41
(1) Case4-1順向流場 41
(2) Case4-2逆向流場 41
3.4.8右板冷卻下板加熱. 41
(1) Case5-1順向流場 41
(2) Case5-2逆向流場 42
3.4.9左板加熱右板冷卻. 42
(1) Case6-1順向流場 42
(2) Case6-2逆向流場 42
3.5. 無因次質傳遞率Sh值分析 43
3.5.1 Sh與Grt之關係 43
3.5.2 Sh與熱質順向、逆向之關係 43
3.5.3 Sh與封閉盒放置傾斜角度情況之關係 43
四、 結論 44
五、參考文獻 46
圖1. 等腰直角三角形封閉盒座標系統與尺寸圖 49
圖2. 電化學法電路設備示意圖 49
表1. 邊界條件說明一覽表 50
圖3. 雷射光暗影法設備示意圖 50
圖4. 本實驗密閉盒之幾何型態與邊界條件示意圖 51
圖5. 溫度分布及濃度分布量測點示意圖 52
圖6. Case 1-1雷射光暗影法流場型態 53
圖7. Case 1-2雷射光暗影法流場型態 58
圖8. Case 1-3雷射光暗影法流場型態 63
圖9. Case 1-4雷射光暗影法流場型態 68
圖10. Case 2-1雷射光暗影法流場型態 73
圖11. Case 2-2雷射光暗影法流場型態 78
圖12. Case 2-3雷射光暗影法流場型態 83
圖13. Case 2-4雷射光暗影法流場型態 88
圖14. Case 3-1雷射光暗影法流場型態 93
圖15. Case 3-2雷射光暗影法流場型態 98
圖16. Case 3-3雷射光暗影法流場型態 103
圖17. Case 3-4雷射光暗影法流場型態 108
圖18. Case 4-1雷射光暗影法流場型態 113
圖19. Case 4-2雷射光暗影法流場型態 116
圖20. Case 5-1雷射光暗影法流場型態 119
圖21. Case 5-2雷射光暗影法流場型態 122
圖22. Case 6-1雷射光暗影法流場型態 126
圖23. Case 6-2雷射光暗影法流場型態 129
圖24. Case 1-1無因次溫度分布圖 132
圖25. Case 1-2無因次溫度分布圖 134
圖26. Case 1-3無因次溫度分布圖 136
圖27. Case 1-4無因次溫度分布圖 138
圖28. Case 2-1無因次溫度分布圖 140
圖29. Case 2-2無因次溫度分布圖 142
圖30. Case 2-3無因次溫度分布圖 144
圖31. Case 2-4無因次溫度分布圖 146
圖32. Case 3-1無因次溫度分布圖 148
圖33. Case 3-2無因次溫度分布圖 150
圖34. Case 3-3無因次溫度分布圖 152
圖35. Case 3-4無因次溫度分布圖 154
圖36. Case 4-1無因次溫度分布圖 156
圖37. Case 4-2無因次溫度分布圖 158
圖38. Case 5-1無因次溫度分布圖 160
圖39. Case 5-2無因次溫度分布圖 162
圖40. Case 6-1無因次溫度分布圖 164
圖41. Case 6-2無因次溫度分布圖 166
圖42. Case 1-1無因次濃度分布圖 168
圖43. Case 1-2無因次濃度分布圖 170
圖44. Case 1-3無因次濃度分布圖 172
圖45. Case 1-4無因次濃度分布圖 174
圖46. Case 2-1無因次濃度分布圖 176
圖47. Case 2-2無因次濃度分布圖 178
圖48. Case 2-3無因次濃度分布圖 180
圖49. Case 2-4無因次濃度分布圖 182
圖50. Case 3-1無因次濃度分布圖 184
圖51. Case 3-2無因次濃度分布圖 186
圖52. Case 3-3無因次濃度分布圖 188
圖53. Case 3-4無因次濃度分布圖 190
圖54. Case 4-1無因次濃度分布圖 192
圖55. Case 4-2無因次濃度分布圖 194
圖56. Case 5-1無因次濃度分布圖 196
圖57. Case 5-2無因次濃度分布圖 198
圖58. Case 6-1無因次濃度分布圖 200
圖59. Case 6-2無因次濃度分布圖 202
圖60. 固定Grm= 9.35×107,Grt與Sh之關係圖 204
[1]S. Ostrach, "Natural convection with combined buoyancy forces", physico chem. hydrodyn, Vol. 1, pp.233-247, (1980).
[2]H. Stommel, A. B. Arons and D. Blanchard, "An ocean graphical curiosity the perpetual salt fountain", deep. sea res., Vol. 15, pp.275-280, (1956).
[3]J.S. Turner, "The behavior of a stable salinity gradient heat from below", j. fluid mech., Vol. 33,pp.183-200, (1968).
[4]C.R. Wilke, M. Eisenberg and C.W. Tobias, "Correlation of limiting currents under free convection conditions", j. of the electrochemical society, Vol. 100, pp.513-523, (1953).
[5]V.G. Levich, "Physicochemical hydrodynamics (1st edition) ", p.281 prentice-hall,englewood cliffs nj, (1962).
[6]T. Mizushina, "The electrochemical method in transport phenomena", adv. heat transfer, Vol. 7, pp.87-161, (1971).
[7]Y. Kamotani, L.W. Wang, S. Ostrach and H.D. Jiang, "Experimental study of natural convection in shallow enclosures with horizontal temperature and concentration gradients", int. j. heat mass transfer,Vol. 28, No.1, pp. 165-173, (1985).
[8]L.W. Wang and D.J. Sun, "Convection mass transfer inenclosures with vertical temperature and concentration" j. of national cheng-kung university, Vol. 20,pp.313-322, (1985).
[9]L.W. Wang and C.C. Chou, "Experimental study of natural convection heat and mass transfer in an enclosure with a cold Inner cylinder", experimental heat transfer, Vol. 4, pp.367-380, (1991).
[10]Arnab Kumar De, Amaresh Dalal, "A numerical study of natural convection around a square,horizontal,heated cylinder placed in an enclosure", Heat and Mass Transfer (2006).
[11]Bassam A/K Abu-Hijleh, "Optimized use of baffles for reduced
Natural convection heat transfer from a horizontal cylinder", int. journal of thermal sciences, (2003).
[12]E.H. Bishop and C.T. Carley, "Photographic studies of natural convection between concentric cylindders", proc. heat transfer fluid mech. inst, pp.63-78, (1966).
[13]R.E. Powe, C.T. Carley and S.L. Carruth, "A numerical solution for natural convection in cylindrical annuli", j. heat transfer Vol. 92, pp.210-220, (1971).
[14]D.N. Mahony, R. Kumar and E.H. Bishop, "Numerical investigation of variable property effects on laminar natural convection of gases between two horizontal isothermal concentric cylinders", asme j. heat transfer , Vol. 108, pp.783-789, (1986).
[15]T.H. Kuehn and R.J. Goldstein,"An experimental and theoretical study of natural convection in the annulus between horizontal concentric cylinders", j. fluid mech. 74, pp.695-719, (1976).
[16]T.H. Kuehn and R.J. Goldstein, "A parametric study of prandtl number and diameter ratio effects on natural convection heat transfer in horizontal cylindrical annuli", j. heat transfer 102, pp.768-770, (1980).
[17]T.H. Kuehn and R.J. Goldstein,"Correlating equations for natural convection heat transfer between horizontal circular cylinders", int.j. heat mass transfer 19, pp.1127-1134, (1976).
[18]L. Crawford and R. Lemlich, "Natural convection in horizontal concentric cylindrical annuli", i.e.c. fund.j. pp.260-264, (1962).
[19]V. Projahn, H. Reiger and H. Beer, "Numerical analysis of laminar convection between concentric and eccentric cylinders", numerical. heat transfer 4, pp.131-146, (1981).
[20]L.W. Wang and C.Y. Wei, "Thermosolutal convection heat and mass transfer in a vertical annular enclosure", experimental heat transfer Vol. 5, pp.315-328, (1992).
[21]J. Dosch and H. Beer, "Numerical simulation and holographic visualization of double diffusive convection a horizontal concentric annulus", int.j.heat mass transfer 35.pp.1811-1821,(1992).
[22]L.W. Wang, Y.C. Kung and S.D. Lai, "Heat and mass transfer in an inclined semi-annular enclosure", chinese journal of mechanics-series a, Vol.20, (2004).
[23]陳國誌,『具上隔板環狀封閉區域中熱質之自然對流現象』, 私立元智大學,碩士論文,民國89年。
[24]楊宗達,『具下隔板環狀封閉區域中熱質之自然對流現象』, 私立元智大學,碩士論文,民國89年。
[25]C. Gau and K.H. Wu, "A nonuntrusive technique for concentration distribution measurement in an enclosure", experiment heat transfer, Vol. 2, pp.215-226,(1989).
[26]Qi-Hong Deng, Guang-Fa tang, "Numerical visualization of mass and heat transport for conjugate natural convection heat conduction by streamline and heatline", heat and mass transfer (2001)
[27]V.A.F.COSTA “Double diffusive natural convection in a square enclosure with heat and mass diffusive walls. int.j.heat mass transfer, Vol.40,No.17,pp.4061-4071,(1997).
[28]Mark P . Dyko , Kambiz Vafai ,"Effects of gravity modulation on convection in a horizontal annulus" ,heat and mass transfer (2006).
[29]Joo-Sik Yoo, "Dual steady solutions in natural convection between horizontal concentric cylinders", int.j.heat and fluid flow, 17:587-593, (1996).
[30]G. Cesini, M. Paroncini, G. Cortella, M. Manzan, "Natural convection from a horizontal cylinderin a rectangular cavity", int.j. heat and mass transfer42, 1801-1811, (1999).
[31]Yasin Varol, Hakan F.Oztop, Asaf Varol.,"Free convection in porous media filled right-angle triangular enclosures", Int.j. heat and mass transfer33, 1190-1197,(2006).
[32]Hakan F.Oztop, Yasin Varol, Ahmet Koca, "Laminar natural convection heat transfer in a shed roof with or without eave for summer season", Applied Thermal Engineering27, 2252-2265,(2007).
[33]Yasin Varol, Hakan F.Oztop, Tuncay Yilmaz, "Natural convection in triangular enclosures with protruding isothermal heater", Int.j. heat and mass transfer50, 2451-2462,(2007).
[34]戴延南,『熱質源壁具雙凸塊之密閉盒的熱質對流現象研究』, 私立元智大學,碩士論文,民國95年。
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