| 研究生: |
李冠賢 Guan-shian Li |
|---|---|
| 論文名稱: |
垂直放置鰭片之自然對流熱傳性能實驗研究 An experimental investigation of natural convection heat transfer in vertical fin |
| 指導教授: |
楊建裕
Chien-yuh Yang |
| 口試委員: | |
| 學位類別: |
碩士 Master |
| 系所名稱: |
工學院 - 機械工程學系 Department of Mechanical Engineering |
| 畢業學年度: | 98 |
| 語文別: | 中文 |
| 論文頁數: | 121 |
| 中文關鍵詞: | 自然對流 、垂直平板 、直線鰭片 、斷續型鰭片 |
| 外文關鍵詞: | flat plate, straight fin, offset strip fin, natural convection |
| 相關次數: | 點閱:6 下載:0 |
| 分享至: |
| 查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報 |
本實驗在固定鰭片正向面積條件下,設計九種不同幾何尺寸及型式之散熱鰭片,包括:垂直平板、直線鰭片、斷續型鰭片、漸長斷續型鰭片。改變直線鰭片的鰭片間距、鰭片高度,及斷續型鰭片的鰭片長度,以實驗方法探討鰭片垂直放置時的自然對流熱傳性能,及各參數對熱傳性能的影響。
垂直平板平均熱傳係數最高,但因散熱面積較小,所以總熱傳量最低。鰭片間距為影響直線鰭片熱傳係數的主要參數,鰭片間距較寬時,熱傳係數較高,間距16 mm直線鰭片比間距7 mm直線鰭片熱傳係數高79 ~ 114 %。而鰭片高度並無法顯著影響鰭片熱傳係數,高度15 mm直線鰭片平均熱傳係數比間距7 mm直線鰭片僅高6 ~ 20 %。斷續型鰭片單一鰭片長度,對斷續型鰭片平均熱傳係數並無顯著影響,且斷續型鰭片和有相同鰭片間距的間距7 mm直線鰭片平均熱傳係數約相同。
An experimental investigation of natural convection heat transfer in nine vertical fins having the same frontal area is described. There are four types of fin which are flat plate fin, straight fin, offset strip fin and offset strip increase in length fin with different space, height and length of discrete plates.
Flat plate fin has highest heat transfer coefficient and smallest heat transfer rate in all fins. The chief geometric feature for effecting on heat transfer coefficient is fin space. Larger fin space leads to higher heat transfer coefficient. Heat transfer coefficient for 16 mm space of straight fin is better then 7 mm space by 79 ~ 114 %. Fin height effects on heat transfer coefficient insignificantly. Heat transfer coefficient for 15 mm height of straight fin is better then 7 mm space by 6 ~ 20 %. Length of discrete plates of offset strip fin effects on heat transfer coefficient insignificantly. In the same fin space, the heat transfer coefficient of offset strip fin is almost equal to the 7 mm space of straight fin.
Aibara, T., 1968, “Natural Convective Heat Transfer in Vertical Parallel Fins of Rectangular Profiles,” The Japan Society of Mechanical Engineers (JSME), Vol. 34. Quoted in Yeh, L. T., Chu, R. C., 2002, Thermal Management of Microelectronic Equipment, ASME Press, New York.
Andrea de Lieto, V., Grignaffini, S., and Gugliermetti, F., 1999, “Optimum Design of Vertical Rectangular Fin Arrays,” International Journal of Thermal Science, Vol. 38, pp. 525-529.
Bar-Cohen, A., and Rohsenow, W. M., 1984, “Thermally Optimum Spacing of Vertical, Natural Convection Cooled, Parallel Plates,” Journal of Heat Transfer, Vol. 106, pp. 116-123.
Bejan, A., 2003, “Optimal Internal Structure of Volumes Cooled by Single Phase Forced and Natural Convection,” ASME Journal of Electronic Packaging, Vol. 125, pp. 200-207.
Elenbaas, W., 1942, “Heat Dissipation of Parallel Plates by Free Convection,” Physica, Vol. 9, No. 1, pp. 1-28. Quoted in Incropera, F. P., and DeWitt, D. P., 2002, Fundamentals of Heat Mass Transfer, 4th ed., John Wiley & Sons, New York.
Fitzroy, N. D., 1971, “Optimum Spacing of Fin Cooled by Free Convection,” Journal of Heat Transfer, Vol. 93, pp. 462-463.
Gebhart, B., Jaluria, Y., Mahajan, R. L., and Sammakia, B., 1988, Buoyancy-In-
duced Flows and Transport, Hemisphere Publishing, Washington, DC.
Guglielmini, G., Nannei, E., and Tanda, G., 1987, “Natural Convection and Radiation Heat Transfer from Staggered Vertical Fins,” International Journal of Heat and Mass Transfer, Vol. 30, No. 9, pp. 1941- 1948.
Guvenc, A., and Yuncu, H., 2001, “An Experimental Investigation on Pe- rformance of Fins on a Horizontal Base in Free Convection Heat Tr- ansfer,” Heat and Mass Transfer, Vol. 37, pp. 409-416.
Harahap, F., and Setio, D., 2001, “Correlations for Heat Dissipation and Natural Convection Heat-Transfer From Horizontally-Based, Vertically-Finned Arrays,” Applied Energy, Vol. 69, pp. 29-38.
Incropera, F. P., and DeWitt, D. P., 2002, Fundamentals of Heat Mass Transfer, 4th ed., John Wiley & Sons, New York.
Ledezma, G. A., and Bejan, A., 1997, “Optimal Geometric Arrangement of Staggered Vertical Plates in Natural Convection,” ASME Journal of Heat Transfer, Vol. 119, pp. 700-708.
Martynenko, O. G., and Khramtsov, P. P., 2005, Free Convection Heat Transfer, 1st ed., Springer Berlin Heidelberg, New York.
McAdams, W. H., 1954, Heat Transmission, 3rd ed., McGraw-Hill, New York.
Ostrach, S., 1953, “An Analysis of Laminar Free Convection Flow and Heat Transfer about a Flat Plate Parallel to the Direction of the Generating Body Force,” National Advisory Committee for Aeronautics, Report 1111.
Reynell, M., 1990, “Advanced Thermal Analysis of Packaged Electronic Systems Using Computational Fluid Dynamics Techniques,” Comp- uuter-Aided Engineering Journal, Vol. 7, pp. 104-106.
Sparrow, E. M., and Prakash, C., 1980, ” Enhancement of Natural Convection Heat Transfer by a Staggered Array of Discrete Vertical Plates,” Journal of Heat Transfer, Vol. 102, pp. 215-220.
Starner, K. E., and McManus, H. N., 1963, “An Experimental Investigation of Free Convection Heat Transfer from Rectangular Fin Arrays,” Journal of Heat Transfer, Vol. 85, pp. 273-278.
Tanda, G., 1993, “Natural Convection Heat Transfer From a Staggered Vertical Plate Array,” ASME Journal of Heat Transfer, Vol. 115, pp. 938-945.
Van de Pol, D. W., and Tierney, J. K., 1973, “Free Convection Heat Transfer from Vertical Fin-Arrays,” IEEE Transactions on Parts, Hybrids, and Packaging, Vol. PHP-10, No. 4, pp. 267-271.
Yeh, L. T., Chu, R. C., 2002, Thermal Management of Microelectronic Equipment, ASME Press, New York.
黃政德,2005,以EHD技術增加LED散熱效率之研究,國立清華大學動力機械工程學系碩士論文,新竹。