Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/91415
標題: Heat transfer enhancement of circular tube inserted with spring coil
圓管內裝置螺旋彈簧之熱傳增強效果
作者: 陳誠安
Cheng-An Chen
關鍵字: heat transfer enhancement
wire coil
Nusselt number
friction factor
performance index
熱傳增強
彈簧線圈
紐塞數
摩擦因子
性能指數
引用: [1] T. S. Ravigururajan, A. E. Bergles, 'Development and verification of general correlations for pressure drop and heat transfer in single-phase turbulent flow in enhanced tubes', Exp. Thermal Fluid Sci, Vol. 13, pp. 55-70, 1996. [2] 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. [3] A. Garcia, J. P. Solano, P. G. Vicente, A. Viedma, 'The influence of artificial roughness shape on heat transfer enhancement: Corrugated tubes, dimpled tubes and wire coils', Applied Thermal Engineering, Vol. 35, pp. 196-201, 2012. [4] A. Garcia, J. P. Solano, P. G. Vicente, A. Viedma, 'Enhancement of laminar and transitional flow heat transfer in tubes by means of wire coil inserts', Int. J. Heat Mass Transfer, Vol. 50, pp. 3167-3189, 2007. [5] S. K. Saha, 'Thermal and friction characteristics of laminar flow through rectangular and square ducts with transverse ribs and wire coil insert', Exp. Thermal Fluid Sci, Vol. 34, pp. 63-72, 2010. [6] H.Y. Kim, S. Koyama, W. Matsumoto, 'Flow pattern and flow characteristics for counter-current two-phase flow in a vertical round tube with wire-coil inserts', Int. J. Multiphase Flow, Vol. 27, pp. 2063-2081, 2001. [7] P. Naphon, 'Effect of coil-wire insert on heat transfer enhancement and pressure drop of the horizontal concentric tubes', Int. Comm. Heat Mass Transfer, Vol. 33, pp. 753-763, 2006. [8] S. Y. Won, P. M. Ligrani, 'Comparisons of flow structure and local numbers in channels with parallel-and crossed-rib tabulators', Int. J. Heat Mass Transfer, Vo1. 47, pp. 1573-1586, 2004. [9] M. A. Akhavan-Behabadi, R. Kumar, M. R. Salimpour, R. Azimi, 'Pressure drop and heat transfer augmentation due to coiled wire inserts during laminar flow of oil inside a horizontal tube', Int. J. Thermal Sci, Vol. 49, pp. 373-379, 2010. [10] P. Promvonge, 'Thermal enhancement in a round tube with snail entry and coil-wire inserts', Int. Comm. Heat Mass Transfer, Vol. 35, pp. 623-629, 2008. [11] S. Gunes, V. Ozceyhan, O. Buyukalaca, 'Heat transfer enhancement in a tube with equilateral triangle cross sectioned coiled wire inserts', Exp. Thermal Fluid Sci, Vol. 34, pp. 684-691, 2010. [12] P. Promvonge, N. Koolnapadol, M. Pimsarn, C. Thianpong, 'Thermal performance enhancement in a heat exchanger tube fitted with inclined vortex rings', Applied Thermal Engineering, Vol. 62, pp. 285-292, 2014. [13] T. Bali, B. A. Sarac, 'Experimental investigation of decaying swirl flow through a circular pipe for binary combination of vortex generators', Int. Comm. Heat Mass Transfer, Vol. 53, pp. 174-179, 2014. [14] 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. [15] 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. [16] A. Garcia, P.G. Vicente, A. Viedma, 'Experimental study of heat transfer enhancement with wire coil inserts in laminar-transition-turbulent regimes at different prandtl number ', Int. J. Heat Mass Transfer, Vol. 48, pp. 4640-4651, 2005. [17] M. C. S. Reddy, V. V. Rao, 'Experimental investigation of heat transfer coefficient and friction factor of ethylene glycol water based TiO2 nanofluid in double pipe heat exchanger with and without helical coil inserts', Int. Comm. Heat Mass Transfer, Vol. 50, pp. 68-76, 2014. [18] M. Saeedinia, M. A. Akhavan-Behabadi , M. Nasr, 'Experimental study on heat transfer and pressure drop of nanofluid flow in a horizontal coiled wire inserted tube under constant heat flux', Exp. Thermal Fluid Sci, Vol. 36, pp. 158-168, 2012. [19] G. Sandhu, K. Siddiqui, A. Garcia, 'Experimental study on the combined effects of inclination angle and insert devices on the performance of a flat-plate solar collector', Int. J. Heat Mass Transfer, Vol. 71, pp. 251-263, 2014. [20] 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。 [21] 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。 [22] 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。 [23] 沈其, '熱傳增強管之熱傳性能比較', 國立中興大學機械工程研究所碩士論文,2013。 [24] F. P. Incropera, and D. P. Dewit, Fundamentals of Heat and Mass Transfer, 3th edition, John Wiley & Sons, 1990. [25] S. J. Kline and F. A. McClintock, 'Describing uncertainties in single-sample experiments', Mechanical Engineering, Vol. 75, pp. 3-8, 1953. [26] Y. A. Cengel, Heat transfer : a practical approach , international edition, R. R. Donnelley & Sons, 1998.
摘要: Heat transfer and pressure drop data in smooth tubes inserted with various wire coils were measured respectively. Water and air were individually considered as working fluid. The wire diameter (e) and pitch (p) of the wire coils were in the range 1 - 1.8 mm and 18 - 32 mm respectively. For tightness between the wire coil and tube wall, three tubes with different inner diameters (12.8, 13.4 and 13.8 mm) were adopted. This work not only established correlations of Nu and f, but also examined performance indexes (r 1 , r 2 and r 3 ) of the test tubes. The r 1 represents the ratio of Nu values between a test tube and a smooth tube; the r 2 denotes the ratio of Nu/f values; the r 3 stands for the ratio of heat transfer rates based on per unit of consumed mechanical power. For air, the correlation of Nu value was found to be Nu = 0.00585(Re)m [(e / d )2 -0.0042]-0.24 ( p / d )-0.22 where m1= 0.51 + 6.16( e / d )-23.15( e / d ) 2 . For water, Nu = 2.55(Re)0.57 ( e / d )α3 ( p / d )-1.13= -0.17( p / d ) + 0.65 . For both air and water, a common f correlationwhere α 3 was acquired as follows: f = 36.13Re −0.36 (e / d )[ln( p / d )]−0.52 . The Nu and r 1 values increase with the e/d value, but increase with a decrease of the p/d value. As the e/d value decreases or the p/d values increases, the r 2 and r 3 values tend to increase. For air, the r 2 and r 3 values moderately increase with the Re value. For water, the r 2 and r 3 values decrease with an increase of the Re value. Keywords: heat transfer enhancement;wire coil;Nusselt number;friction factor;performance index
本實驗探討光滑圓管內部插入彈簧線圈後對工作流體與管壁間之熱傳 增強與壓力降之影響,工作流體分為空氣與水等兩種,所採用彈簧線圈之線徑(e)分為 1 mm、1.4 mm 及 1.8 mm 等三種,節徑(p)則分為 18 mm、24 mm及 32 mm 等三種,並依照彈簧線圈與管壁間之緊密程度,配置所需之圓管,因此測試管之內徑(d)分為 12.8 mm、13.4 mm 及 13.8 mm 等三種。此研究不僅探討 Nu 值與 f 值之相關性,同時也進行測試管之三種性能係數(r1 、r2 及r 3 )之比較,其中 r 1 值代表插入彈簧線圈之測試管與光滑圓管間 Nu 值之比值,r 2 值為兩者間 Nu/f 值之比值,而 r 3 則表示兩者間消耗每單位機械摩損功所獲得的熱傳量之比值。對工作流體為空氣而言,量測所得之 Nu 值經由相關性分析後,可得一組經驗公式為 Nu = 0.00585(Re)m [(e / d )2 -0.0042]-0.24 ( p / d )-0.22 ,1m1其中= 0.51 + 6.16( e / d )-23.15( e / d ) 2 ;對水而言,所獲得之熱傳相關性公式為 Nu = 2.55(Re)0.57 (e / d )α ( p / d )-1.13 ,其中 α 3 = -0.17( p / d ) + 0.65 ;而無論工作流體為水或空氣,摩擦因子(f)之經驗公式為 f = 36.13Re −0.36 (e / d )[ln( p / d )]−0.52 。熱傳(空氣與水)量測之結果顯示,Nu 值與 r 1 值均會隨著 p/d 值之增加而減少,但兩者皆會隨著 e/d 值的增加而增大,因此若要得到較大的熱傳效果,須採用較小 p/d 值與較大 e/d 值之彈簧線圈。而在 e/d 值越小與 p/d 值越大之情形下,r 2 值與 r 3 值均會越大。對空氣而言,r 2 與 r 3 值會隨著 Re 值之增加而略微增大;對水而言,此 r 2 與 r 3 值會隨著 Re 值之增加而減小。 關鍵字:熱傳增強;彈簧線圈;紐塞數;摩擦因子;性能指數
URI: http://hdl.handle.net/11455/91415
文章公開時間: 2018-07-15
Appears in Collections:機械工程學系所

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