臺灣博碩士論文加值系統

在工業界，藉由發熱面上使用毛細結構來增進沸騰熱傳的技術，可改善熱傳性能，間接縮小蒸發器的體積，降低製造成本、節省空間，並且增進系統的效率。本文旨在使用樹枝狀銅粉和添加孔洞成型劑的方法，燒結具有雙孔徑的毛細結構，藉由增加結構中大孔的體積比例和孔隙度來增強沸騰熱傳。高瓦數時，大孔提供氣體離開的管道，降低液體與氣體之間的相對流阻，同時小孔洞吸入流體補充至相變化發生處，以提升臨界熱通量與熱傳。
本實驗使用絕對壓力5.5 bar 時的飽和冷媒R-134a，於水平測試表面進行池沸騰熱傳增強研究。實驗結果顯示，單孔與雙孔徑毛細結構的熱傳係數最高可達120 與70 kW/m2K。熱傳增強比例最高分別為光滑平面的 11倍與8倍。單孔徑毛細結構性能提升的原因在於樹枝狀粉末擁有較廣大的熱傳面積及通道，能夠加速薄液膜的蒸發速率。雙孔徑毛細結構由於孔隙度較高，有效熱傳導面積減少，以致熱傳性能較差。不過，高熱通量時，具有較高孔隙度的雙孔徑毛細結構，由於擁有許多大孔，所以確實延後了臨界熱通量的發生，達到869 kW/m2，為光滑平面的2.2倍，單粉燒結面的1.3倍。單孔與雙孔徑毛細結構皆有效提升了臨界熱通量與降低壁面過熱度。

On the tendency of higher and higher power density devices in modern technology, the need for more effective heat exchangers have motivated the development of enhanced surfaces. Therefore, the central purpose in presented research is to enhance boiling heat transfer capacity by utilizing two pore size distributions of a biporous surface structure. This surface is sintered from the mixture of dendritic copper powders and the pore former, Na2CO3, which formed the larger pores in the matrix. By changing the volumetric ratio of pore former, it’s able to alter the porosity and the numbers of larger pores in the porous media. At high heat flux, the larger pores provide venting passages for bubbles generated inside the structure and reduce the liquid-vapor counterflow resistance adjacent to the surface, while the smaller pores continue to function as liquid supply routes.
The experiments were conducted with the 3-cm diameter test surfaces, horizontally oriented, and submerged in saturated R-134a, at an absolute pressure of 5.5 bar. At low heat flux, the results show that the heat transfer coefficients of mono and biporous surfaces are up to 120 and 70 kW/m2K, respectively. The heat transfer enhancement ratios are 9~11 and 4~8 compared to a smooth surface. At high heat flux, due to the larger pores in the porous structure, the biporous surface really prolongs the critical heat flux to 869 kW/m2, which is about 2.2 and 1.3 times over a smooth and monoporous surface, respectively.
Future research is needed to optimize the mixture of the pore former and cooper powders, which can result in substantial further enhancement.

致謝 i
中文摘要 ii
英文摘要 iii
目錄 iv
圖目錄 vii
表目錄 ix
符號說明 x

第一章 緒論 1
1.1研究動機與背景 1
1.2文獻回顧 3
1.2.1特殊表面熱傳增強文獻 3
1.2.2毛細結構表面文獻回顧 5
1.3研究目的 11

第二章 實驗原理與理論分析 13
2.1池沸騰熱傳與沸騰曲線圖 13
2.2池沸騰中核沸騰曲線之預測公式 16
2.3臨界熱通量 18
2.4毛細結構沸騰熱傳 19
2.5具毛細結構表面之臨界熱通量 19

第三章 毛細結構的設計與製造 21
3.1毛細結構的製造 21
3.1.1實驗材料 21
3.1.2製造設備 22
3.1.3銅粉之選擇 23
3.1.4孔洞成形劑之選擇 24
3.1.5混合方式 26
3.1.6製造步驟 26
3.2毛細結構參數量測 28
3.2.1冷態測試系統 28
3.2.1.1孔隙度 28
3.2.1.2有效孔徑 29
3.3實驗設計 31

第四章 實驗設備與方法 33
4.1熱性能測試系統 33
4.1.1加熱系統 33
4.1.2測試容器 34
4.1.3冷凝與輔助控溫系統 34
4.1.4資料擷取系統 35
4.2實驗步驟與方法 38
4.2.1實驗步驟 38
4.2.2實驗方法 38
4.3實驗數據換算 39
4.3.1冷媒熱物理性質 39
4.3.2熱散失計算 39
4.3.3壁面溫度計算 40
4.3.4熱傳係數計算 40
4.3.5熱傳增強比例計算 40
4.4誤差分析 41

第五章 結果與討論 43
5.1冷態性能測試 43
5.2光滑表面熱傳性能測試 46
5.2.1熱傳比較 46
5.2.2臨界熱通量比較 48
5.3單粉燒結表面之熱傳性能測試 50
5.4雙孔燒結表面之熱傳性能測試 54
5.5沸騰照片比較 59

第六章 結論與建議 63
6.1結論 63
6.2建議 64
參考文獻 65
附錄 71

Afgan, N. H., Jovic, L. A., Kovalev, S. A., and Lenykov, V. A., (1985). "Boiling heat-transfer from surfaces with porous layers." International Journal of Heat and Mass Transfer, 28(2), 415-422.

Albertson, C.E., (1977). "Boiling heat transfer surface and method. " U.S. patent no.4,018,264.

Benjamin, J. E., and Westwater, J. W., (1961). "Bubble growth in nucleate boiling of a binary mixture." International Developments in Heat Transfer, ASME, New York, 212-218.

Bergles, A. E., and Chyu, M.C., (1982). "Characteristics of nucleate pool boiling from porous metallic coatings." Journal of Heat Transfer-Transactions of the ASME, 104, 279-285.

Bergles, A. E., (1997). "Enhancement of pool boiling." International Journal of Refrigeration, 20(8), 545-551.

Bonilla, C. F., Grady, J. J., and Avery, G. W., (1965). "Pool boiling heat transfer from grooved surfaces." Chem. Eng. Prog. Supp. Ser., 61(57), 280-288.

Cieslinski, J. T., (2002). "Nucleate pool boiling on porous metallic coatings." Experimental Thermal and Fluid Science, 25(7), 557-564.

Collier, J., G., and Thome, J., R., (1994) "Convective boiling and condensation. " Oxford Science Publications, 3rd edition.


Cooper M.G., (1984). "Heat flow rates in saturated nucleate pool boiling—a wide-ranging examination using reduced properties. "Advances in Heat Transfer, 16, 157-239, Academic Press.

Furberg, R., Li, S., Palm, B., Toprak, M., and Muhammed, M.,(2006) "Dendritically ordered nano-particles in a micro-porous structure for enhanced boiling. " 13th International Heat Transfer Conference, NAN-07.

Gorenflo, D., (1993). "Pool boiling." VID Heat Atlas, Chapter Ha, Germany: VDI-Verlag GmbH.

Grant A. C., and K. J. W., (1980). "Thermospray method for production of Aluminium porous boiling surface. " U.S. patent no. 4,232,056.

Griffith P., and Wallis J.D., (1960). "The role of surface conditions in nucleate boiling. " Chemical Engineering Progress Symposium Series, 56(30), 49-63.

Hsieh, S. S., and Weng, C. J., (1997). "Nucleate pool boiling from coated surfaces in saturated R-134a and R-407c. " International Journal of Heat and Mass Transfer, 40, 519-532.

Hsu, Y. Y., (1962). "On the size range of active nucleation cavities on a heating surface. " Journal of Heat Transfer, 84, 207-216.

Hwang, G. S., and Kaviany, M., (2006). "Critical heat flux in thin, uniform particle coatings." International Journal of Heat and Mass Transfer, 49(5-6), 844-849.

Incropera, F. P., and Dewitt, D.P., (2001). " Fundamentals of heat and mass transfer " 5th Ed, Wiley, Ch.11, 642-673.
Jakob, M., and Fritz, W., (1931). "Versuche tiber den verdamp fungsvorgang. "Forschung auf dem Gebiete des lngenieurwesens, 2, 435-437.

Jakob, M., (1949). "Heat transfer. " Wiley, New York, 636-638.

Kaviany, M., (1999). "Principles of heat transfer in porous media. " 2nd Ed, Springer Verlag, New York Inc.

Kim, J. H., Rainey, K. N., You, S. M., and Pak, J. Y., (2002). "Mechanism of nucleate boiling heat transfer enhancement from microporous surfaces in saturated FC-72." Journal of Heat Transfer-Transactions of the ASME, 124(3), 500-506.

Kline, S. J., (1985). "The purposes of uncertainty analysis." Journal of Fluids Engineering-Transactions of the ASME, 107, 153-163.

Leinhard, J. H., Dhir, V. K., and Riherd, D. M., (1973). "Peak pool boiling heat flux measurements on finite horizontal plates." Journal of Heat Transfer, 95, 477.

Leinhard, J. H., and Dhir, V. K., (1973). "Extended hydrodynamic theory of the peak and minimum pool boiling heat fluxes." National Aeronautics and Space Administration Report NASA-CR-2270

Liter, S. G., and Kaviany, M., (2001). "Pool-boiling CHF enhancement by modulated porous-layer coating: theory and experiment." International Journal of Heat and Mass Transfer, 44(22), 4287-4311.

Malyshenko, S. P., (1991). "Features of heat-transfer with boiling on surfaces with porous coatings." Thermal Engineering, 38(2), 81-88.

Mitrovic, J., and Ustinov, A., (2006a). "Boiling features of novel microstructure. " 13th International Heat Transfer Conference.

Mitrovic, J., (2006b). "How to create an efficient surface for nucleate boiling? "International Journal of Thermal Sciences , 45(1), 1-15.

Milton, R. M., (1968). "Heat exchange system. " U.S. patent no. 3,384,154.

Muellejans, H., (1982). "Process for the preparation of a surface of a metal wall for the transfer of heat. " U.S. patent no. 4,360,058.

Nishikawa, K., Ito, T., and Tanka, K., (1979). "Enhanced heat transfer by nucleate boiling on a sintered metal layer." Heat Transfer-Japanese Research, 8, 65-81.

Nukiyama, S., (1934). "Maximum and minimum values of heat transmitted from metal to boiling water under atmospheric pressure." Journal of Society of Mechanical Engineers, Japan, 37, 367.

Oconnor, J. P., and You, S. M., (1995). "A painting technique to enhance pool boiling heat-transfer in saturated FC-72." Journal of Heat Transfer-Transactions of the ASME, 117(2), 387-393.

Polezhaev, Y. V., and Kovalev, S. A., (1990). "Modelling heat transfer with boiling on porous structures." Thermal Engineering, 37(12), 617-620.

Poniewski, M. E., (2004). "Peculiarities of boiling heat transfer on capillary-porous coverings." International Journal of Thermal Sciences, 43(5), 431-442.


Ribatski, G., and Thome, J. R., (2006). "Nucleate boiling heat transfer of R134a on enhanced tubes." Applied Thermal Engineering, 26(10), 1018-1031.

Rohsenow, W. M., (1962). "A method of correlating heat transfer data for surface boiling of liquids." Journal of Heat Transfer-Transactions of the ASME, 84, 969.

Stubos, A. K., and Buchlin, J. M., (1999). "Enhanced cooling via boiling in porous layers: The effect of vapor channels." Journal of Heat Transfer-Transactions of the ASME, 121(1), 205-210.

Thome, J. R., (1990). "Enhanced boiling heat transfer,. " Hemisphere Publisher Corporation, New York, USA.

Thome, J. R., (2006)."Engineering Databook III. " Available from:<http://www.wlv.com/products/databook/db3DataBookIII.pdf>.

Webb, R. L., (1983). "Nucleate boiling on porous coated surfaces." Heat Transfer Engineering, 4(3-4), 71-82.

Webb, R. L., (2005). "Principles of enhanced heat transfer." 2nd ED, John Wiley & Sons, Inc., New York, 311-371.

Wu, W., Du, J. H., Hu, X. J., and Wang, B. X., (2002). "Pool boiling heat transfer and simplified one-dimensional model for prediction on coated porous surfaces with vapor channels." International Journal of Heat and Mass Transfer, 45(5), 1117-1125.

Zuber, N., (1958). "Hydrodynamic aspects of boiling heat transfer. " AECU-4439, Physics and Mathematics, US Atomic Energy Commission.

賴玟全, (2002). "LDV輔助雙管池沸騰熱傳動態量測與熱傳機制模擬" 國立中山大學碩士論文。

張千喬, (2002). "高性能沸騰表面在晶片散熱之研究" 長庚大學碩士論文。

林岳儒, (2003). "孔隙結構對燒結式熱導管性能之影響" 國立台灣大學碩士論文。

范智峰, (2004). "冷媒R-134a與R-404A在熱傳增強管上之池沸騰觀察與熱傳性能分析" 國立中央大學博士論文。

施志憲, (2006). "具偏斜曲線毛細結構之迴路式熱管" 國立台灣大學碩士論文。

林修緯, (2006). "雙孔徑毛細結構於迴路式熱管之熱傳增強研究" 國立台灣大學碩士論文。