Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/91416
標題: Dependence of heat transfer and pressure drop on arc diameter of internal ring-type ribs in circular tube
圓管內部突出環節之溝徑對熱傳與壓降之影響
作者: 龔育威
Yu-Wei Gong
關鍵字: heat transfer enhancement
ring-type protrusions
friction factor
Nusselt number
performance index
熱傳增強
突出環節
摩擦因子
紐塞數
性能指數
引用: 參考文獻 [1] R. L. Webb, E. R. Eckert, and R. J. Goldstein 'Heat Transfer and Friction in Tubes with Repeated-Rib Roughness ', Int. J. Heat Mass Transfer, Vo1. 14, pp. 601-617, 1971. [2] J. H. Royal and A. E. Bergles, 'Augmentation of Horizontal In-Tube Condensation by Means of Twisted-Tape Inserts and Internally Finned Tubes', J. Heat Transfer , Vo1. 100, pp. 17-24, 1978. [3] D. L. Gee, and R. L. Webb, 'Forced Convection Heat Transfer in Helically Rib-Roughened Tubes', Int. J. Heat Mass Transfer, Vo1. 23, pp. 1127-1136, 1980. [4] E. M. Sparrow, K. K. Koram and M. Charmchi, 'Heat Transfer and Pressure Drop Characteristics Induced by a Slat Blockage in a Circular Tube', J. Heat Transfer, Vo1. 102, pp. 64-70, 1980. [5] R. Sethumadhavan, and M.R. Rao, 'Turbulent Flow Heat Transfer and Fluid Friction in Helical-Wire-Coil-Inserted Tubes', Int. J. Heat Mass Transfer, Vo1. 26, pp. 1833-1845, 1983. [6] B. W. Webb and S. Ramadhyani, 'Conjugate Heat Transfer in a Channel with Staggered Ribs', Int. J. Heat Mass Transfer, Vo1. 28, pp. 1679-1687, 1985. [7] S. B. Uttarwar and M. R. Rao, 'Augmentation of Laminar Flow Heat Transfer in Tubes by Means of Wire Coil Inserts', J. Heat Transfer, Vo1. 107, pp. 930-935, 1985. [8] G. H. Junkhan, A. E. Bergles , V. Nirmalan and T. Ravigururajan, 'Investigation of Turbulators for Fire Tube Boilers', J. Heat Transfer , Vo1. 107, pp. 354-360, 1985. [9] J.L. Fernandez and R. Poulter, 'Heat Transfer Enhancement by Means of Flag-type Insert in Tubes', Int. J. Heat Mass Transfer, Vo1. 30, pp. 2603-2609, 1987. [10] S. Nozu, H. Honda and S. Nishida, 'Condensation of a Zeotropic CFC114 - CFC113 Refrigerant Mixture in the Annulus Double-Tube Coil with an Enhanced Inner Tube', Exp. Thermal Fluid Sci., Vo1.11, pp. 364-371, 1995. [11] W.Y.C.C. Wang, Y. Z. Robert and L.W. Huang, 'Film Condensation of HCFC-22 on Horizontal Tubes', Int. Comm. Heat Mass Transfer, Vo1. 23, pp. 79-90, 1996. [12] S. Wang, Z. Y. Guo and Z. X. Li, 'Heat Transfer Enhancement by Using Metallic Filament Insert in Channel Flow', Int. J. Heat Mass Transfer, Vo1. 44, pp. 1373-1378, 2001. [13] M. Goto, N. Inoue and N.Ishiwatari, 'Condensation and Evaporation Heat Transfer of R410A inside Internally Grooved Horizontal Tubes', Int. J. Heat Mass Transfer, Vo1. 24, pp. 628-638, 2001. [14] V. Zimparov, 'Enhancement of Heat Transfer by a Combination of a Single-Start Spirally Corrugated Tubes with a Twisted Tape', Exp. Thermal Fluid Sci, Vo1.25, pp. 535-546, 2002. [15] S.Y. Won and P.M. Ligrani, 'Comparisons of Flow Structure and Local Numbers Numbers in Channels with Parallel-and Crossed-Rib Tabulators', Exp. Thermal Fluid Sci, Vo1. 47, pp. 1573-1586, 2004. [16] W. Molki and K.L. Bhamidipati, 'Enhancement of Convective Heat Transfer in the Developing Region of Circular Tubes Using Corona Wind', Int. J.Heat Mass Transfer, Vo1. 47, pp. 4301-4314, 2004. [17] D.W . Zhou., 'Heat Transfer Enhancement of Copper Nanofluid with Acoustic Cavitation', Int. J. Heat Mass Transfer, Vo1. 47, pp. 3109-3117, 2004. [18] 黃文傑, '圓管突出環節對空氣熱傳增強的影響', 國立中興大學機械工程研究所碩士論文, 2004。 [19] 王培堂, '圓管內部連續突出環節對水流與管壁間之熱傳增強的影響',國立中興大學機械工程研究所碩士論文, 2005。 [20] 陳俊忠, '圓管內部突出環節之圓弧尺寸大小對熱傳增強之影響', 國立中興大學機械工程研究所碩士論文, 2006。 [21] S.J. Kline and F.A. McClintock, 'Describing Uncertainties in Single-Sample Experiments', Mechanical Engineering, Vol. 75, pp. 3-8, 1953.
摘要: This work investigated the effect of groove diameter (da) of internal ring-type protrusions in circular tubes on the heat transfer and pressure drop. Totally twelve test tubes were tested. Protrusion pitch to tube diameter ratios (p/d) of the test tubes were 0.72, 1.45, and 2.9. Protrusion height to tube diameter ratios (e/d) were 0.043 and 0.069. In addition, three groove diameter to tube diameter ratios (da/d), 0.14, 0.43 and 0.72, were considered. The obtained heat transfer and fluid friction data were compered to those of a smooth tube. Two working fluids, air and water, were individually considered. The Reynolds numbers (Re) were in the range of 3502 to 17850. The result shows that, at the same p/d, e/d and Re values, the Nusselt number (Nu) enhancement index (r1) increases with a decrease of the da/d value, while the Nu/friction factor (f) index (r2) and the heat transfer rate/comsumed mechanical work index (r3) increase with the da/d values. Either air or water, the larger the da/d value, the better the overall heat transfer and pressure drop performance. For air, at p/d=1.45, e/d=0.043 and da/d=0.72, a largest r3 value of 0.62 was found and it occurs at Re=16011. For water, at the same p/d, e/d, and da/d values, the largest r3 valus was 0.53 and it occurs at Re=14215. Comparing the r1, r2, and r3 values shows that the tube with p/d=1.45, e/d=0.043 and da/d=0.72 consumes less mechanical work than the other tubes. Correlation result shows that the Nu and f values are proportional to (da/d)-0.05 and (da/d)-0.13 respectively.
此研究以實驗方法測試銅管內部突出環節之溝徑(da)對熱傳與壓降之影響。本實驗中所採用的銅管之節徑-管徑比值(p/d)有0.72、1.45、2.9三種,環節深度-管徑比值(e/d)有0.043、0.069兩種,溝徑-管徑比值(da/d)則有0.14、0.43、0.72三種,總計共有十二支試驗管,量測之紐塞數(Nu)與摩擦因子(f)最後皆和一支內部平滑圓管量測之結果進行比較,量測中之工作流體分為空氣與水等兩種,雷諾數(Re)的範圍介於3502到17850間。熱傳增強管與平滑圓管之比較結果顯示,在相同之p/d、e/d與Re值下,隨著da/d值之增加,Nu增強比值(r1)會隨之略為減少;Nu增強-摩損增加比值(r2)會隨之增加,此代表Nu值增大之幅度會較f值增大之幅度為大;而熱傳量增強-摩耗功增加之比值(r3)亦也隨之增加,由分析之結果可以得知,不論對空氣或水而言,較大之da/d值(較大之環節圓弧大小)會得到較佳之熱傳與壓力降之綜合效果。當工作流體為空氣時,p/d=1.45、e/d=0.043與da/d=0.72之試驗管在Re=16011時,所得之r3=0.62為所有測試管中之最大r3值;而在工作流體為水時,相同之試驗管在Re=14215時,所得之r3=0.53為所有測試管中之最大r3值。綜合比較三個性能指數(r1、r2與r3值)後得知,當熱傳增強管為p/d=1.45、e/d=0.043及da/d=0.72時,會消耗較少之機械功,同時亦能維持較好的熱傳量。實驗量測之結果經相關性之分析後,可以得知Nu值大致正比於(da/d)-0.05;而f值大致正比於(da/d)-0.13。
URI: http://hdl.handle.net/11455/91416
文章公開時間: 2017-08-31
Appears in Collections:機械工程學系所

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