第四章 結果與討論
4.5 實驗結果歸納
騰曲線比較。兩端封閉的臨界熱通量只有四端開放的一半。圖 4-29 為間隙 S
開放式因為溫度超越現象所造成的溫度偏移較Θ=45 ∘及Θ=90 ∘來的嚴重。
圖 4-32 為Θ＝０°時，本實驗開放式及 S=0.5 mm 與 Bergles 等[27]的池沸 騰曲線比較。Bergles 在一大氣壓下，以鰭片為加熱面，FC-72 為工作流體的池沸 騰實驗。在低過熱度時，S=0.5mm 熱通量高於開放式，其中開放式與本實驗開 放式皆有溫度偏移的情況。S=0.5mm 的臨界熱通量低於開放式許多，和本實驗 的情況相同，這說明當加熱面為水平時，小間隙對臨界熱通量有嚴重的抑制作用。
圖 4-1 熱損估算
圖 4-2 θ=0 ﾟ，S=3mm 時的沸騰曲線
過熱度ΔT(K)
圖 4-3 θ=0 ﾟ，S=2mm 時的沸騰曲線
圖 4-4 θ=0 ﾟ，S=1mm 時的沸騰曲線
過熱度ΔT(K)
圖 4-5 θ=0 ﾟ，S=0.5mm 時的沸騰曲線
過熱度ΔT(K)
圖 4-6 θ=0 ﾟ時四種間隙與開放式的池沸騰曲線
過熱度ΔT(K)
圖 4-7 θ=0 ﾟ時四種間隙與開放式在低熱通量的池沸騰曲線放大圖
圖 4-8 θ=0 ﾟ時四種間隙與開放式的熱傳係數
圖 4-9 θ =0 ﾟ時四種間隙與開放式在低熱通量的熱傳係數放大圖
過熱度ΔT(K)
圖 4-10 θ=45 ﾟ，S=3mm 時的池沸騰曲線
過熱度ΔT(K)
圖 4-11 θ=45 ﾟ，S=2mm 時的池沸騰曲線
過熱度ΔT(K)
圖 4-12 θ=45 ﾟ，S=1mm 時的池沸騰曲線
過熱度ΔT(K)
圖 4-13 θ=45 ﾟ，S=0.5mm 時的池沸騰曲線
過熱度ΔT(K)
圖 4-14 θ=45 ﾟ時四種間隙與開放式的池沸騰曲線
過熱度ΔT(K)
圖 4-15 θ=45 ﾟ時四種間隙與開放式在低熱通量的池沸騰曲線放大圖
圖 4-16 θ=45 ﾟ時四種間隙與開放式的熱傳係數
圖 4-17 θ=45 ﾟ時四種間隙與開放式在低熱通量熱傳係數放大圖
過熱度ΔT(K)
圖 4-18 θ=90 ﾟ，S=3mm 時的池沸騰曲線
過熱度ΔT(K)
圖 4-19 θ=90 ﾟ，S=2mm 時的池沸騰曲線
圖 4-20 θ=90 ﾟ，S=1mm 時的池沸騰曲線
過熱度ΔT(K)
圖 4-21 θ=90 ﾟ，S=0.5mm 時的池沸騰曲線
過熱度ΔT(K)
圖 4-22 θ=90 ﾟ時四種間隙與開放式的池沸騰曲線
過熱度ΔT(K)
圖 4-23 θ=90 ﾟ時四種間隙與開放式在低熱通量的池沸騰曲線放大圖
圖 4-24 θ=90 ﾟ時四種間隙與開放式的熱傳係數
圖 4-25 θ=90 ﾟ時四種間隙與開放式在低熱通量熱傳係數放大圖
低熱通量(60 2 KW m )
中熱通量(120 2
KW m )
高熱通量(180 2
KW m )
圖 4-26 Θ＝０°，開放式加熱面在不同熱通量下氣泡情況
低熱通量(60 2
KWm ) 中熱通量(80 2
KW m ) 高熱通(100 2 KW m )
圖 4-27(a) Θ＝９０°，間隙 S=0.5mm 時不同熱通量下氣泡情況
低熱通量(60 2
KWm ) 中熱通量(120 2
KWm ) 高熱通(160 2 KW m )
圖 4-27(b) Θ＝９０°，間隙 S=1mm 時不同熱通量下氣泡情況
低熱通量(60 2
KWm ) 中熱通量(120 2
KW m ) 高熱通(180 2 KW m )
圖 4-27(c) Θ＝９０°，間隙 S=2mm 時不同熱通量下氣泡情況
低熱通量(60 2
KWm ) 中熱通量(120 2
KW m ) 高熱通(180 2 KW m )
圖 4-27(d) Θ＝９０°，間隙 S=3mm 時不同熱通量下氣泡情況
低熱通量(60 2
KW m ) 中熱通量(120 2
KW m ) 高熱通(180 2 KWm )
圖 4-27(e) Θ＝９０°，開放式時不同熱通量下氣泡情況
圖 4-28 Θ＝０°，S=0.5mm 兩端封閉與四端開放的池沸騰曲線
圖 4-29 Θ＝90°，S=0.5mm 兩端封閉與四端開放的池沸騰曲線
補充液體
補 充 液 體
(a)四端開放 (b)兩端封閉
圖 4-30 Θ＝０°加熱時液體補充情形
補充液體
補充液體 (a)四端開放 (b)兩端封閉
圖 4-31 Θ＝９０°加熱時液體補充情形
圖 4-32 Θ＝０°，本實驗與 Bergles[27]的池沸騰曲線
第五章結論及未來方向
附錄
依照以上公式可以用來分析本實驗所須計算的總熱通量q"total，熱損失q"loss，過 熱度ΔT，及熱傳係數h。
參考文獻
1. Nukiyama,S.,1934,"The maximum and MinimumValue of Heat Transfer from Metal to Boiling Waterunder Atmosphere Pressure ",Int.J.Heat Mass Tran,Vol.9, pp.1419-1433。
2. Volmer,1945,"M.Kinetik der Phasenbildung",Edwards Bros.,Ann Arbor。
3. Bar-Cohen,A., 1992,"State-of-the Art and Trends in the Thermal Packaging of the Electronic Equipment ",J.Electronic Packaging,V.114,pp.257-270。
4. Oktay,S.,1994, "Beyond Thermal Limits in the Computers Systems",Kluwer Academic Public,Dor drecht。
5. Isaacson,E.,Isaacson,M.,1975,"Dimensional Methods in Engineering and Physics", Edward Arnold,London
6. Katto,Y.,1978,"Generalized Correlations for Critical Heat Flux of Natural Convection Boiling in Confined",Trans. JSME ,v.44 ,pp.3908-3911。
7. Yao,S. C.,Chang,Y.,1983,"Pool Boiling Heat Transfer in a Confined Space",Int. J.
Heat Mass Trans.,v.26,pp. 841-847。
8. Bar-Cohen,A., Rohsenow,W. M.,1984,"Thermally Optimum Spacing of Vertical Natural Convection Cooled Plates",J. Heat Trans.,v.106,PP.116-123。
9. Fujita,Y.,Ohta,H.,Uchida,S. and Nishkawa,K.,1988,"Nucleate Boiling Heat Transfer and Critical Heat Flux in Narrow Space between Rectangular Surfaces",Int. J. Heat and Mass Trans.,v.31,pp.229-238。
10. Katto,Y.,Yokoyo,S. and Teraoka,,K.,1992"Nucleat and Transition Boiling in Narrow Space between Two Horizontal Parallel Disk Surfaces Bull",JSME20, v.143,pp.638-643。
11. Xia,C.,Guo,z.and Hu,W.,1992,"Mechanism of Boiling Heat Transfer in Narrow Channels",in proc,28th Nat Heat Trans.Conf,pp.111-119。
12. Rampisela,P.F.,1993,"Etude experimentable de l’e´bullitionen espace confin´e",The´se de Doctorat,INPG,Grenobe,France,p.193。
13. Bonjour,J.,Zaghdoudi,M.C.,Lallemand,M.,1996,"Prediction of Heat Transfer Coefficient During Nucleate Pool Boiling in Vertical Channels",Eurotherm Seminar no48 on Pool Boiling,pp.201-208。
14. Tingwei Guo,Tingying Zhu,1997,"Experimental Research on The Enhancement of Boiling Heata Transfer of Liquid Helium in NarrowChannel", Cryogenics, v.37, pp.67-70。
15. Misale,M.,Bergles,A. E.,1997," The Influence of Channel Width on Natural Convection and Boiling Heat Transfer from Simulated Microelectronic Components",Experimental Thermal and Fluid Science,v.14,pp.187-193。
16. Bonjoyr,J.,Lallemand,M.,1998,"Flow Patterns During Boiling in a Narrow Space
Between Two Vertical Surfacs",Int.J.Multiphase Flow,v.24,pp.947-960。
17. Misale,M.,Guglielmin,G.,Frogheri,M. and Bergles,A. E.,1999, "FC-72 Pool Boiling from Finned Surfaces Placed in a Narrow Channel: Preliminary Results",Heat and Mass Transfer,v.34,pp.449-452。
18. 陳文忠,2002,"Study of Pool Boiling of Dielectric Fluid FC-72 Between Two Plates",國立交通大學碩士論文。
19. 李俊賢,2003,"Study of Enhanced Pool Boiling of Dielectric Fluid FC-72 Between Two Plates＂,國立交通大學碩士論文。
20. You,S. M.,Bar-Cohen,A. and Simon,T. W.,1995," Effect of Dissolved Gas Content on Pool Boiling of a Highly Wetting Fluid",J.Heat Transfer vol.117,p.p687-692。
21.Aderson,T.M,Mudawar,I.,1989,"Microelectronic Cooling by Enhanced Pool Boiling of a Dielectric Fluorocarbon Liquid",J.Heat Tranfer,vol.111,pp.752-759。
22.Fujiia,M.,Nashiyama,E.,Yamanaka G,1979,"Nucleate Pool Boiling Heat Transfer from Micro-porous Heating Surface", Advances in Enhanced Heat Transfer,ASME,pp.45-51。
23.Nishikawa,K.,Fujita,Y.,Uchida,S.andOhta,H.,1994,"Effectof Surface Configuration on Nucleate Boiling Heat Transfer",Int.J.Heat and Mass Transfer,v.27,pp.1559 -1571。
24.You,S. M.,Bar-Cohen,A. and Simon,T. W.,1995," Experiments on Nucleate Boiling Heat Transfer with a Highly-Wetted Dielectric Fluids:Effect of Pressure Subcooling and Dissolved Gas Content", J.Heat Transfer,vol.118,pp.564-571。
25.You,S. M.,Bar-Cohen,A. and Simon,T. W.,1990,"Boiling Incipience and Nucleate Boiling Heat Transfer of Highly-Wetted Dielectric Fluids From Electronic Materials",InterSociety Conference on Thermal Phenomena。
26.Bergles,A.E,Chyu,M.C,1981,"Characteristics of Nucleat Pool Boiling from Porous Metallic Coatings",Advances in Enhanced Heat Transfer,ASME HTD, vol.18,pp.61-71。
27.Gulielmini G.,Misale M., Frogheri M., Bergles A.E.,1999,"FC-72 Pool Boiling from Surface Placed In a Narrow Channel:Preliminary Result", Int. J. Heat Mass Trans,v.34,pp. 449-452。
28.Rohsenow,W.M.,1952,"A Method of Correlating Heat Transfer Data for Surface Boiling of Liquids",Trans.ASME,vol.74,pp.969-975。
29.Mikic,B.B., Rohsenow,W.M.,1969,"A New Correation of Pool Boiling Data Including the Effect of Heating Surface Characterfistics",J.of Heat Transfer,pp.245-250。
30.Gjerkes,Henrik and Iztok,Globic,2002," Measurement of Certain Parameters Influencing Activity of Nucleation Sites in Pool Boiling ",Experimental Thermal and Fluid Science,v.25,pp. 487-493。
31.Bonjour,Jocelyn,Clausse,Marc and Lallemand,Monique,2000,"Experimental Study of The Coalescence Phenomenon during Nucleate Pool Boiling",Experimental Thermal and Fluid Science,v.20,pp.180-187。
32.Watwe,A. A.,1996, "Measurment and Prediction of The pool Boiling Critical Heat Fluxin Highly Wetting Fluids" , Ph.D. Dissertation , University of Minnesota, Minnesota。
33.Zuber,N.,1959,"Hydrodynamic Aspects of Boiling Heat Transfer",AEC Report no.AECU-4439,Physicsand Mathematics。
34.Monde,M.,Inoue,T. and Mitsutake,Y.,1997,"Critical Heat Flux in Pool Boiling on a Vertical Heater",Heat and Mass Transfer,v.32,pp.435-440。
35.Gu,J. M.,Lu,M,1999,"The New Assumption for Calculating Heat Transfer in Pool Boiling",Heat and Mass Transfer,v.35,pp. 295-297。
36.3M Company,Physical Properties Data, 2002 ,Private Communication,Katoka Japan。
37.Kline,S.J.,1985, "The Purpose of Uncertainty Analysis", J. Fluids Engineering, v.107,pp.153-160。
38.Rini,Daniel P.,Chen,Ruey-Hung and Chow,Louis C.,2001," Bubble Behavior and Heat Transfer Mechanism in FC-72 Pool Boiling ",Experimental Heat Transfer,v.14,pp.27-44。
39.Nowell,Jr.,R.M.,S.H. and Jaeger,R.C.,1995,"Effect of Channel Width on Pool Boiling from a Microconfigured Heat Sink",IEEE Trans. Comp.,Packaging,and Manufact Technol,v.18,No.3,pp.534-539。