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研究生:劉韋良
研究生(外文):Wel-Liang Liu
論文名稱:向下火焰延燒寬度與邊牆效應之研究
論文名稱(外文):向下火焰延燒寬度與邊牆效應之研究
指導教授:蔡匡忠蔡匡忠引用關係
指導教授(外文):Kuang-Chung Tsai
學位類別:碩士
校院名稱:國立高雄第一科技大學
系所名稱:環境與安全衛生工程研究所
學門:工程學門
學類:環境工程學類
論文種類:學術論文
論文出版年:2016
畢業學年度:104
語文別:中文
論文頁數:72
中文關鍵詞:寬度效應向下火焰延燒邊牆效應
外文關鍵詞:downward flame spreadwidth effectsidewall effect
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  • 被引用被引用:2
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摘要
火災大多起因於小火,若周圍持續供應可燃性物質,小火則會持續延燒成大火。延燒可在地面上或任何可燃物質上發生,由於延燒設置位置不同(例如:牆面、地面),使得火焰延燒方向及周圍氣流流動方向有所差異又可分為順流(concurrent)以及逆流(counter current),在牆面火焰延燒模式當中,因延燒方向不同可分為有向上延燒及向下延燒,在向上延燒過程中因延燒方向與周圍氣流之流動方向相同亦為順流(concurrent)在向下延燒因延燒方向與周圍氣流流動方向相異即為逆流(counter current)。
先前研究已指出牆面向上延燒中存在寬度效應延燒速率隨寬度增加而增加,但對於垂直向下延燒部分研究甚少,因此為能更詳細了解火焰延燒現象,利用邊牆的有無與寬度不同來觀察向下火焰延燒。
本研究以實驗來探討在向下延燒中寬度效應以及邊牆效應對向下延燒之影響,實驗使用五種不同寬度PMMA及有無邊牆進行,其寬度分別為100、200、300、500及700 mm之試體,高度為1000 mm、厚度10 mm進行牆面向下火焰延燒。
實驗結果發現,對於窄試體而言(寬度=100mm)邊牆的存在阻擋試體兩側進氣,並使可燃性蒸氣沿邊牆流動,增加了火焰的厚度。而無邊牆狀況下試體周圍進氣朝向燃燒燃料的中心線。
而寬度變化影響試體周圍進氣,在有邊牆之較窄試體(100mm)時兩側邊牆使可燃性蒸氣蓄積,進而提高火焰厚度,當寬度增加邊牆產生之影響漸小火焰厚度隨之變薄,而無邊牆時寬度增加影響周圍進氣,使兩側之空氣捲入方向朝試體中心線,導致可燃性蒸氣靠近中心線,使火焰厚度隨寬度增加,但觀察延燒速率可發現在向下延燒過程當中有無邊牆狀況下,火焰延燒速率並無受到寬度變化所影響,此外在各寬度之無邊牆延燒速率也較有邊牆延燒速率高。
Abstract
A fire may spread once combustible materials are nearby, and the heat flux onto them is sufficient. The flame spread can be divided into concurrent and counter-current spread, depending on the directions of flame spread and hot gas flow. One of the example of the concurrent flame spread is upward flame spread, while downward flame spread belongs to the counter-current one.
The width and sidewall effects with upward flame spread have been studied. This study investigated the existence of width and sidewall effects of downward flame spread experimentally. The material used was 10 mm thick and 1000 mm high PMMA slabs with width of 100, 200, 300, 500 and 700 mm. The presence of sidewalls was studied. Flame height, flame temperature, flame thickness, heat release rate per unit area and flame spread rate were measured. The experimental results show that the width of fuel changes the direction of entrained air flow. The presence of sidewalls helps volatiles flow along the sidewalls, increasing flame thickness. This phenomenon was significant for narrow specimens. The absence of sidewalls resulted in lateral entrained air flow toward the center line of burning fuel.
The experimental results show that the width of fuel did not influence the downward flame spread rate with or without sidewalls. Additionally, the downward flame spread rates without sidewalls were higher than those with sidewalls.
摘要 I
Abstract III
誌謝 V
目錄 VI
圖目錄 VII
表目錄 X
第一章、緒論 1
1.1研究動機與目的 1
1.2研究範圍 2
1.3研究方法及步驟 3
第二章、文獻回顧 5
2.1火焰延燒 5
2.2向上火焰延燒 9
2.2.1加熱範圍 9
2.2.2加熱強度 13
2.2.4寬度效應 18
2.2.5邊牆效應 21
2.3向下火焰延燒 24
2.3.1加熱範圍 24
2.3.2向下延燒實驗 28
2.3.3寬度效應 31
2.3.4邊牆效應 33
第三章、寬度及邊牆效應對向下火焰延燒之實驗設計 39
3.1實驗目的 39
3.2實驗設備 39
3.3牆面向下延燒之寬度及邊牆效應設計 40
3.4實驗設計量測項目 42
3.5實驗進行方法 43
第四章、實驗結果及討論 45
4.1邊牆效應對向下延燒之實驗結果及討論 45
4.1.1小結 54
4.2寬度效應實驗結果及討論 55
4.2.1無邊牆之寬度效應實驗結果及討論 61
4.2.3小結 66
第五章、結論 67
參考文獻 68
1. Drysdale D, An Introduction to Fire Dynamics, Second Edition, John Wiley and Sons, 1998
2. Quintiere J, Harkleroad M and Hasemi Y, Wall Flames and Implications for Upward Flame Spread, Combustion Science and Technology, Vol.48, pp.191-222, 1986
3. Aeklund TI, A Vortex Model for Wall Flame Height,Journal of Fire Science, Vol.14, pp.4-14, 1986
4. Delichatsios MA, Flame Heights in Turbulent Wall Fires with Significant Flame Radiation, Combustion Science and Technology, Vol.39, pp.195-214, 1984
5. Saito K, Quintiere JG and Williams FA, Upward Turbulent Flame Spread, Fire Safety Science-Proceedings of the First International Symposium, pp.75-86, 1985
6. Hasemi Y, Experimental Wall Flame Heat Transfer Correlations for the Analysis of Upward Wall Flame Spread, Fire Science and Technology, Vol.14, No.2, pp. 75-90,
7. Sugawa O, Satoh H and Oka Y, Flame Height from Rectangular Fire Sources Considering Mixing Factor, Fire Safety Science- Proceedings of the Third International Symposium, pp. 435-444, 1991
8. Coutin M, Most JM, Delichatsios MA and Delichatsios MM, Flame Heights in Wall Fires:Effects of Width, Confinement and Pyrolysis Length, Fire Safety Science- Proceedings of the Sixth International Symposium, pp. 729-740, 1999
9. Tu KM and Quintiere JG, Wall Flame Heights with External Radiation, Fire Technology, pp. 195-203, 1991
10. Orloff L, De Ris J and Markstein GH, Upward Turbulent Fire Spread and Burning of Fuel Surface, The 15th Symposium (International)on Combustion, pp. 183-192, 1974
11. Tsai KC and Drysdale D, Flame Height Correlation and Upward Flame Spread Modeling, Fire and Material, pp. 279-287, 2002
12. Tsai KC, Width Effect on Upward Flame Spread, Fire Safety Journal, Vol.44, pp. 962-967, 2009
13. Tsai KC, Influence of sidewalls on width effects of upward flame spread , Fire Safety Journal, Vol.46, pp. 294-304, 2011
14. 萬復森,“牆面火焰延燒寬度效應之研究”,國立高雄第一科技大學環境與安全衛生工程研究所碩士論文,民國94年
15. 張柏偉,“外風及邊牆對於牆面向上火焰延燒效應之探討”,國立高雄第一科技大學環境與安全衛生工程研究所碩士論文,民國100年
16. Ahmad T and Faeth GM, Turbulent Wall Fire, 17th Symposium(International)on Combustion, pp. 1149-1160, 1978
17. Kokkala M, Baroudi D and Parker WJ, Upward Flame Spread on Wooden Surface Products: Experiments and Numerical Modelling, Fire Safety Science- Proceedings of the Fifth International Symposium, pp. 309-320, 1997
18. Qian C and Saito K, An Empirical Model for Upward Flame Spread Over Vertical Flat and Corner Walls, Fire Safety Science- Proceedings of the Fifth International Symposium, pp. 285-296, 1997
19. Quintiere JG and Lee CH, Ignitor and Thickness Effects on Upward Flame Spread, Fire Technology, Vol.34, No.1, pp. 18-38, 1998
20. Tsai KC and Drysdale D, Using Cone Calorimeter Data for The Prediction of Fire Hazard, Fire Safety Journal, Vol.37, pp. 697-706, 2002
21. Tsai KC and Drysdale D, Upward Flame Spread:Heat Transfer to Unburned Surface, The 7th Symposium of IAFSS, 2001
22. Wang HY, Coutin M and Most JM, Large-Eddy-Simulation of Buoyancy-Driven Fire Propagation Behind a Pyrolysis Zone Along a Vertical Wall, Fire Safety Journal, Vol.37, pp. 259-285, 2002
23. Rangwala AS, Buckley SG and Torero J, Upward Flame Spread on a Vertically Oriented Fuel Surface:The Effect of Finite Width, Proceedings of The Combustion Institute, Vol.31, pp.2607-2615, 2007
24. Pizzo Y, Conclave JL, Querre P, Coutin M and Porterie B, Width Effects on Early Stage of Upward Flame Spread over PMMA Slabs:Experimental Observations, Fire Safety Journal, Vol.44, pp. 407-414, 2009
25. de Ris, J. N., Proceedings of the Combustion Institute, Vol. 12,pp.241-2521,1969
26. Hirano T, Kanno Y. In: Proceedings of the 14th symposium on combustion. pp. 391–8, 1973
27. Lin P-H and Chen C-H. Numerical analyses for downward flame spread over thin and thick fuels in a gravitational field. Combust Flame; 118: 744–746, 1999
28. Ayani MB, Esfahani JA and Mehrabian R. Downward flame spread over PMMA sheets in quiescent air, Fire Safety Journal, pp.164–169, 2006
29. Kun zhao, Xiaodong Zhou, Lizhong Yang, Junhui Gong, Zhibo Wo, Zufei Huan, Xueqiang Liu, Width effect on downward flame spread over poly (methyl methacrylate) sheets, Journal of Sciences, Vol.33, pp.69-84, 2015
30. Weiguang An, Huahua Xiao, Jinhua Sun, K.M Liew, Weigang Yan, Yang Zhou, Lin Jiang, Xinjie Huang, Effects of sample width and sidewalls on downward flame spread over XPS slabs. Fire Safety Science pp. 234-247,2014
31. Weigang Yan, Yang Shen, Lin Jiang, Weiguang An, 2014, Experimental study of sidewall and pressure effect on vertical downward flame spread over insulation material, The 10th Asia-Oceania Symposium on Fire Science and Technology.
32. F. A. Williams, Combustion Theory: The Fundamental Theory of Chemically Reacting Flow Systems: Perseus Books Group, 1985.
33. S. Bhattacharjee, J. West, and R. A. Altenkirch, Determination of the spread rate in opposed-flow flame spread over thick solid fuels in the thermal regime, Symposium (International) on Combustion, vol. 26, pp. 1477-1485, 1996.
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