跳到主要內容

臺灣博碩士論文加值系統

(44.201.97.224) 您好!臺灣時間:2024/04/18 03:19
字體大小: 字級放大   字級縮小   預設字形  
回查詢結果 :::

詳目顯示

我願授權國圖
: 
twitterline
研究生:陳俊男
研究生(外文):Chun-Nan Chen
論文名稱:具雙孔徑毛細結構迴路式熱管之熱傳分析
論文名稱(外文):Heat Transfer Analysis of a Loop Heat Pipe with Biporous Wicks
指導教授:陳瑤明
指導教授(外文):Yau-Ming Chen
學位類別:碩士
校院名稱:國立臺灣大學
系所名稱:機械工程學研究所
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:2008
畢業學年度:96
語文別:英文
論文頁數:79
中文關鍵詞:迴路式熱管雙孔徑毛細結構單孔徑毛細結構熱傳係數
外文關鍵詞:biporous wickmonoporous wickLoop heat pipeheat transfer coefficient
相關次數:
  • 被引用被引用:0
  • 點閱點閱:373
  • 評分評分:
  • 下載下載:0
  • 收藏至我的研究室書目清單書目收藏:0
近年來隨著高功率電子元件等產品對散熱器之熱傳需求不斷提升,如何藉由高性能毛細結構來提升迴路式熱管熱傳能力,是一個重要的課題。本研究旨在添加孔洞成型劑於鎳粉中進行燒結,製造出具雙孔徑分布之毛細結構
,並探討在迴路式熱管內,雙孔徑毛細結構不同孔洞變化下的熱傳性能與行為。研究方法藉由改變孔洞成型劑粒徑(32~88μm)、含量(20~25vol%)以及燒結溫度(650~750℃),搭配使用二水準因子設計的統計方法,分析出各參數對迴路式熱管的熱傳能力之影響程度與趨勢,並建立統計經驗模型,以找出最佳的雙孔徑毛細結構參數。最後,再與單孔徑毛細結構做熱傳性能的比較。
研究結果顯示孔洞成型劑的含量對迴路式熱管熱傳能力的影響程度最大,貢獻百分比為76.8%,其次是孔洞成型劑粒徑貢獻百分比為15.6%,而燒結溫度影響不明顯,貢獻度僅0.2%。並且在孔洞成型劑粒徑縮小、含量增多的情況下,可獲得性能較佳的雙孔徑毛細結構。透過經驗模型之建議,最佳的雙孔徑毛細結構參數為:孔洞成型劑粒徑範圍在20~32μm,孔洞成型劑含量25vol%,燒結溫度750℃。
實際測試結果在熱沉10℃與容許溫度85℃下,結果顯示最佳之雙孔徑毛細結構其總熱傳量可達570W、熱阻為0.08℃/W,比起單孔徑毛細結構的熱傳性能350W、熱阻為0.22℃/W,整體性能具有相當的提升。此外,雙孔徑毛細結構最高熱傳傳係數可達68 KW/m2.℃,與單孔徑毛細結構熱傳係數10 KW/m2.℃相比約提升6.8倍。針對最佳雙孔徑毛細結構明顯先升後降的趨勢,於不同熱通量下可將之分為三個階段,較低熱通量時(約130KW/m2以下)熱傳係數變化平緩,相似於單孔徑毛細結構性能變化。而隨著熱通量之增加(約130~210KW/m2)薄膜蒸發面積得以延伸,導致熱傳係數急速增高。在高熱通情況下(約210KW/m2以上)推測液體薄膜經蒸發已部分乾涸,造成性能逐漸衰退。
In recent years, the high-power electronic devices cause the increasing demand of heat dissipation. Thus, how to improve the heat transfer capacity of a loop heat pipe (LHP) by the wick structure will be an important topic. The purpose of this article is to discuss the heat transfer performance and behavior of biporous wick which made by the mixture of nickel powders and pore former. The study was conducted following a statistical method using a two-level factorial plan involving three variables: the particle of pore former (32~88μm), the pore former content(20~25vol%),and sintering temperature (650~750℃). Moreover, the empirical model was built to determine the optimized parameter combination of the biporous wick. Finally, the heat transport capability of the LHP between monoporous wicks and biporous wicks has been investigated.
The results showed that the pore former content is a primary effect (percent contribution is 76.8%) for performance of LHP. Particle size of pore formers is minor effect (percent contribution is 15.6%), and sintering temperature is a little effect. The better parameters of biporous wick is tend to have smaller particle size of pore former, more pore former contents. The best parameters of the biporous wick is obtained with the empirical model: The range of particle size of pore former is 20~32μm, pore former content is 25vol%, and sintering temperature is 750℃.
Experimental results showed that, at the sink temperature of 10℃ and the allowable evaporator temperature of 85℃, the maximum heat transfer capacity of the best biporous wick achieved 570W and the minimum total thermal resistance was 0.08℃/W. Comparing to a monoporous wick for 350W and 0.22℃/W. In addition, the heat transfer coefficient in the evaporator of the best biporous wick reached to a maximum value of 68KW/m2•℃, which was approximately 6.8 times higher than that of the monoporous wick. With the increase of the imposed heat flux, the heat transfer coefficient of the best biporous wick increases to a maximum value and then decreases afterwards. The special heat transfer curve can be divided into three different regions. In lower heat flux(below 130KW/m2), the heat transfer performance of biporous wick is almost like that of a monoporous wick. The biporous wick had an increased surface area available for thin film evaporation at higher heat flux(130~210KW/m2). Therefore, the heat transfer coefficient reaches rapidly a maximum value. In high heat flux (above 210KW/m2), the performance of biporous wick decay gradually because the dryout starts to occur in the wick.
誌謝 i
摘要 ii
Abstract 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前言 1
1.2文獻回顧 5
1.3研究目的 8
第二章 實驗原理與理論分析 10
2.1迴路式熱管操作原理 10
2.1.1毛細限制 12
2.1.2啟動限制 13
2.1.3液體過冷限制 13
2.1.4補償室體積限制 14
2.2迴路式熱管理論分析 14
2.2.1流動壓降分析 14
2.2.2熱阻分析 15
2.2.2-1 蒸發器熱阻 15
2.2.2-2 冷凝器熱阻 16
第三章 實驗設備與方法 18
3.1雙孔徑毛細結構的設計與製作 18
3.1.1不同種類的雙孔徑毛細結構 18
3.1.2雙孔徑毛細結構材料 19
3.1.3雙孔徑毛細結構製造設備 20
3.1.4雙孔徑毛細結構製造方法 21
3.2雙孔徑毛細結構的參數量測 23
3.2.1孔隙度的量測 23
3.2.2孔徑分布的量測 23
3.2.3滲透度的量測 24
3.3迴路式熱管性能測試設備 25
3.4迴路式熱管之性能評估與誤差分析 27
第四章 實驗設計方法 29
4.1因子的種類 29
4.2模型種類 30
4.2.1二水準因子設計 30
4.2.2中央合成設計 31
4.3反應曲面 32
4.4變異數分析 33
4.5實驗方法與步驟 35
4.5.1設計因子的選擇 36
4.5.2設計因子的範圍 37
4.5.3雙孔徑毛細結構的實驗設計 39
第五章 結果與討論 42
5.1實驗與統計分析 42
5.1.1變異數分析 42
5.1.2雙孔徑毛細結構的反應曲面分析 47
5.1.3追蹤性實驗 48
5.2 雙孔徑毛細結構之熱傳分析 51
5.2.1雙孔徑毛細結構內參數的影響 51
5.2.1-1孔洞成型劑粒徑的影響 51
5.2.1-2孔洞成型劑含量的影響 53
5.2.2 單孔徑毛細結構與雙孔徑毛細結構性能分析與探討 56
第六章 結論 61
6.1結論 61
6.2建議 62
參考文獻 63
附錄 66
[1]Maydanik, Y. F., Fershtater, Y. G., and Pastukhov, V.,“Thermoregulation of Loops with Capillary Pumping for Space Use,” SAE Paper 921169, 1992.
[2]Goncharov, K. A., Loop Heat Pipes in Thermal Control Systems for ‘‘Obzor’’ Spacecraft, Proceedings of the 25th International Conference on Environmental Systems, San Diego, CA, Paper 951555, 1995.
[3]Kozmin, D., Goncharov, K., Nikitkin, M., Maidanik, Y. F., Fershtater, Y. G., and Smirnov, F., “Loop Heat Pipes for Space Mission Mars96,” 26thICES Monterrey, California, 1996.
[4]Liao, Q., and Zhao, T. S., “Evaporative Heat Transfer in a Capillary Transfer,” Vol. 13, No. 1, pp.126-133, 1999.
[5]Vityaz, P. A., Konev, S. K., Medvedev, V. B., and Sheleg, V. K., “Heat Pipes with Bidispersed Capillary Structures,” Proceedings of the 5th International Heat Pipe Conference, Vol. 1, pp. 127–135, 1984.
[6]Konev, S. V., Polasek, F., and Horvat, L., “Investigationof Boiling in Capillary Structures,” Heat Transfer-Soviet Research, Vol.19, No.1, pp.14-17, 1987.
[7]North, M. T., Rosenfeld, J. H. and Shaubach, R. M., “Liquid Film Evaporation from Bidisperse Capillary Wicks in Heat Pipe Evaporators", Proceedings of 9" IHPC, New Mexico, USA, pp.143-147, 1995.
[8]Rosenfeld, J. H. and North, M. T.," Porous Media Heat Exchangers for Cooling of High-power Optical Components", Optical Engineering, Vo1.34, No.2, pp.335-341, 1995.
[9]North, M. T., Sarraf, D. B., Rosenfeld, J. H., Maidanik, Y. F., and Vershinin, S., “High Heat Flux Loop Heat Pipes, ” Proceedings of the 6th European Symposium on Space Environmental Control Systems., Noordwijk, The Netherlands, pp. 371–376, 1997.
[10]Chen, Z. Q., Cheng, P., and Zhao, T. S.,“An Experimental Study of Two Phase Flow and Boiling Heat Transfer in Bi-dispersed Porous Channels,”Int. Commun. Heat Mass Transfer, Vol. 27, No.3, pp. 293–302, 2000.
[11]Wang, J. and Catton I., “Biporous Heat Pipes for High Power Electronic Device Cooling”, Semiconductor Thermal Measurement and Management, 2001. Seventeenth Annual IEEE Symposium, pp.211-218, 2001.
[12]Wang, J. and Catton I., “Evaporation Heat Transfer in Thin Biporous Media”, Journal of Heat and Mass Transfer, Vol.37, No.2, pp.275-281, 2001.
[13]Wang, J., Catton, I., “Vaporization Heat Transfer in Biporous Wicks of Heat Pipe Evaporators,” Proceedings of the 13th International Heat Pipe Conference, Vol. 2, pp. 76–86, 2004.
[14]Cao, X. L., Cheng, P., and Zhao, T.S., “Experimental Study of Evaporative Heat Transfer in Sintered Copper Bidispersed Wick Structures,” J.Thermophys. Heat Transfer, Vol. 16, No.4, pp.547–552, 2002.
[15]Merilo, E., G., Semenic, T., and Catton, I., “Experimental Investigation of Boiling Heat Transfer in Bidispersed Media”, Proceedings of the 13th International Heat Pipe Conference, Vol. 2, pp. 87-93, 2004
[16]Semenic, T., Lin, Y. Y., and Catton, I., 2005a, “Use of Liquid Film Evaporation in Biporous Media to Achieve High Heat Flux over Large Areas,” Proceedings of ASME Summer Heat Transfer Conference, Paper Number HT2005-72238, 2005.
[17]Semenic, T., Lin, Y. Y., Catton, I., and Sarraf, D. B., “Use of biporous wicks to remove high heat fluxes,”Journal of Applied Thermal Engineering Vol.28, No. 4, pp.278-283, 2006.
[18]Semenic, T., and Catton, I., “Boiling and Capillary Limit Enhancement of a Heat Pipe Wick Using Biporous Wick Capillary Structure”, Annals of the Assembly for International Heat Transfer Conference 13. PRT-18 pages, 2006.
[19]Hartenstine, J. R., Richard, W., Bonner III, Montgomery, J. R., and Semenic, T. “Loop Thermosyphon Design for Cooling of Large Area, High Heat Flux Sources,” Proceedings of ASME Summer Heat Transfer Conference, Paper Number IPACK2007-33993, 2007.
[20]Maydanik, Y. F., Vershinin, S. V., Korukov, M. A., and Ochterbeck, J. M., “Miniature Loop Heat Pipes–a Promising Means for Cooling Electronics,” IEEE Transactions of components and packaging technologies, Vol. 28, No. 2, pp.290~296, 2005.
[21]Chuang, P.-Y. A., “An Improved Steady-state Model of Loop Heat Pipes Based on Experimental and Theoretical Analyses,” PhD thesis, The Pennsylvania State University, 2003.
[22]Ku, J., “Operating Characteristics of Loop Heat Pipes,” in: International Conference on Environmental Systems, Denver, 1999 (SAE paper 1999-01-2007).
[23]Hoang, T. T., O''Connell, T. A., Ku, J., Butler, C. D., and Swanson, T. D., “Miniature Loop Heat Pipes for Electronic Cooling”, International Electronic Packaging Technical Conference and Exhibition. Vol.2, pp. 517-525, 2003.
[24]Tracey, V. A., “Pressing and Sintering of Nickel Powders,” The International Journal of Powder Metallurgy & Powder Technology, Vol.20, No.4, pp.281-285, 1984.
[25]Kline, S. J., and McClintock, F. A., “Describing Uncertainties in Single-Sample Experiments”, Mechanical Engineering. Vol. 75, pp. 3-9, 1953.
[26]Montgomery, D. C. Design and analysis of experiments (6th edit.).John Wiely and Sons, New York, USA, 2005
[27]葉怡成,編著「實驗計畫法-製程與設備最佳化」,五南圖書出版公司,2001。
[28]Maidanik, Y. F., “Loop Heat Pipes”, Applied Thermal Engineering, Vol.25, No.5-6, pp. 635-657, 2005.
QRCODE
 
 
 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                               
第一頁 上一頁 下一頁 最後一頁 top
無相關期刊