臺灣博碩士論文加值系統

本論文主要以實驗的方法分析介電液FC-72在水力直徑為1mm及0.67mm的矩形渠道內之冷凝熱傳係數及壓降。熱通量、質通量及蒸汽乾度對於冷凝熱傳係數及壓降的影響有詳細的討論。實驗結果顯示冷凝熱傳係數隨著平均乾度、質通量及熱通量增加而增加，壓降也是隨著平均乾度及質通量增加而增加，但熱通量對於壓降並無明顯的影響。目前通用的Akers及Shah冷凝熱傳關係式對本實驗的實驗結果不能作出準確的預測，都低估本實驗結果，因此修正了Akers的熱傳關係式，以應用在小管徑冷凝器的設計。

This thesis experimentally investigated the characteristics of condensation heat transfer and pressure drop for dielectric fluid FC-72 flowing in horizontal rectangular channels. The rectangular channels have two hydraulic diameters of 1mm and 0.67mm. The effects of the heat flux, mass flux and vapor quality of FC-72 on measured condensation heat transfer and pressure drop were examined in detail. The heat transfer coefficient was shown to be higher at a higher vapor quality, at a higher mass flux and at a higher heat flux. The pressure drop was shown to be higher at a higher vapor quality and a higher mass flux, but the heat flux has no effect on pressure drop. The Akers and Shah correlations did not predict well in this study. For practical design of micro heat exchangers, the empirical correlation was proposed to correlate the present data for the heat transfer coefficient.

中文摘要 I
英文摘要 II
目錄 III
表目錄 IV
圖目錄 V
符號說明 VII
第一章 緒論 1
1-1 研究背景與目的 1
1-2 文獻回顧 2
第二章 實驗系統與方法 11
2-1 工作流體性質 11
2-2 實驗系統結構 11
2-3 實驗量測設備 14
2-4 實驗步驟 15
第三章 實驗分析 21
3-1 熱損實驗 21
3-2 測試管內側介電液之兩相冷凝熱傳係數 22
3-3 測試管內側介電液之流動壓降 23
第四章 實驗結果與討論 25
4-1 實驗範圍 25
4-2 不準度與熱損 25
4-3 實驗數據與討論 25
4-4 關係式比較 28
第五章 結論 54
附錄 55
參考文獻 56

[1] Nusselt, W., 1916, “Die Oberflachenkondesation des Wasserdampfes”, Ver. Deut. Ing., Vol.60, pp.541-546.
[2] Bankoff, S.G., 1960, “A Variable Density Single-fluid Model of Two-phase Flow with Particular Reference to Steam-water Flow”, Trans. ASME J. Heat Transfer, Series C, pp.265-272
[3] Wallis, G.B., 1969, “One Dimensional Two-phase Flow”, McGraw-Hill.
[4] Martin, C.S., 1976, “Vertically Downward Two-phase Slug Flow”, J. of Fluids Engng., 98, Series 1, 4, pp.715-722.
[5] Chen, I.Y., Kocamustafaogullari, G., 1987, “Condensation Heat Transfer Studies for Stratified, Cocurrent Two-phase Flow in Horizontal Tubes”, Int J. Heat Mass Transfer, Vol.30, pp.1133-1148.
[6] Deans, D.A., 1955, “Heat Transfer Coefficient for Freon-12 Condensing within a Horizontal Tube”, Master’s Thesis, Rice Inst., Houston, Texas.
[7] Crosser, D.K., 1955, “Condensation Heat Transfer within Horizontal Tube”, Ph.D. Thesis, Rice Inst., Houston, Texas.
[8] Rossen, H.F., 1957, “Heat Transfer during Condensation inside a Horizontal Tube”, Ph.D. Thesis, Rice Inst., Houston, Texas.
[9] Akers, W.W. et al., 1958, “Condensation Heat Transfer within Horizontal Tubes”, Chem. Eng. Prog. Vol.54, pp.89-90.
[10] Shah, M.M., 1979, “A General Correlation for Heat Transfer during Film Condensation inside Pipes”, Int. J. Heat Mass Transfer, Vol.22, pp.547-556.
[11] Rohsenow, W.M., Weber, J.H., Ling, A.T., 1956, “Effect of Vapor Velocity on Laminar and Turbulent-film Condensation”, Trans. ASME, Vol.78, pp.1637-1643.
[12] Barnea, D., Luninski, Y., Taitel, Y., 1983, “Flow Pattern in Horizontal and Vertical Two Phase Flow in Small Diameter Pipes”, The Canadian J. Chem. Eng., Vol.61, pp.617-620.
[13] Yang C-Y, Webb, R.L., 1996, ”Condensation of R-12 in Small Hydraulic Diameter Extruded Aluminum Tubes with and without Micro-fins”, Int. J. Heat Mass Transfer, Vol.39, pp.791-800.
[14] Kaushik, N., Azer, N.Z., 1988, “A General Heat Transfer Correlation for Condensation inside Internally Finned Tubes”, ASHRAE Trans., Vol.94(2), pp.261-279.
[15] Yan Y-Y, Lin T-F, 1999, “Condensation Heat Transfer and Pressure Drop of Refrigerant R-134a in a Small Pipe”, Int. J. Heat Mass Transfer, Vol.42, pp.697-708.
[16] Wang B-X, Du X-Z, 2000, “Study on Laminar Film-wise Condensation for Vapor Flow in an Inclined Small/Mini-diameter Tube”, Int. J. Heat Mass Transfer, Vol.43, pp.1859-1868.
[17] 吳奇穎, 2001, “Analysis of Condensation Heat Transfer of Dielectric Liquid FC-72”, 國立交通大學機械工程研究所碩士論文.
[18] Yu, W., Choi, S.U.-S., France, D.M., Wambsganss, M.W., 2002, “Single-sided Steam Condensing inside a Rectangular Horizontal Channel”, Int. J. Heat Mass Transfer, Vol 45, pp 3715-3724.
[19] Lu, Q., Suryanarayana, N.V., 1995, “Condensation of a Vapor Flowing inside a Horizontal Rectangular Duct”, ASME J. Heat Transfer, Vol 117, pp418-424.
[20] Akers, W.W., Rosson, H.F., 1960, “Condensation inside a Horizontal Tube”, Chem. Eng. Prog. Symp. Ser., Vol 56, pp 145-149.
[21] Lockhart, R. W., Martinelli, R.C., 1949, “Proposed Correlation of Data for Isothermal Two-phase Two-component Flow in Pipes”, Chem. Eng. Prog., Vol.45, pp.39.
[22] Chisholm, D., 1967, “A Theoretical Basis for the Lockhart-Martinelli Correlation for Two-phase Flow”, Int. J. Heat Mass Transfer, Vol.10, pp.1767-1778.
[23] Friedel, L., 1979, “Improved Friction Pressure Drop Correlation for Horizontal and Vertical Two-phase Pipe Flow”, European Two-Phase Flow Group Meeting, Paper E2, June.
[24] Wambsganss, M. W., 1992, “Frictional Pressure Gradients in Two-phase Flow in a Small Horizontal Rectangular Channel”, Experimental Thermal and Fluid Science, Vol.5, pp.40-56.
[25] Yang C-Y, Webb, R. L., 1996, “Friction Pressure Drop of R-12 in Small Hydraulic Diameter Extruded Aluminum Tubes with and without Micro-fins”, Int. J. Heat Mass Transfer, Vol.39(4), pp.801-809.