預混紊流燃燒：火花引燃機制與加氫效應之定量量測

以作者查詢圖書館館藏

、以作者查詢臺灣博碩士

、以作者查詢全國書目

、勘誤回報

、線上人數：7

、訪客IP：3.16.76.43

姓名

石偉達(Wei-ta Shih) 查詢紙本館藏

畢業系所

能源工程研究所

論文名稱

預混紊流燃燒：火花引燃機制與加氫效應之定量量測
(Premixed Turbulent Combustion: Quantitative Measurements of Spark Ignition Mechanisms with the Consideration of Hydrogen Additions)

相關論文

★ 低氮氧化物燃燒器與加氫效應定量量測	★ 平板式SOFC電池堆流場可視化與均勻度之實驗模擬和分析
★ 平板式SOFC單電池堆性能量測：棋盤狀流道尺寸效應	★ 實驗量測分析Kee＇s燃料電池堆流場分佈模式之可靠度
★ 棋盤式雙極板尺寸效應對固態氧化物燃料電池性能之影響	★ 氫氣/一氧化碳合成氣於高壓層流與紊流環境下之燃燒速度量測
★ 自我加速蜂巢結構球狀火焰及其局部自我相似性之量測與分析	★ 加壓型SOFC陽極支撐與電解質支撐單電池堆量測與分析
★ 高壓預混紊流球狀擴張火焰之自我相似性和其火焰速率於不同Lewis數(Le < 1, Le ≈ 1, Le >1)	★ 實驗研究密度比效應對紊流火焰速率之影響
★ 加壓型氨固態氧化物燃料電池之性能和穩定性量測	★ 平板式加壓型合成氣固態氧化物燃料電池實驗研究
★ 雷射直寫系統最佳化及其單一細胞列印與光電醫學之應用	★ 加壓型合成氣固態氧化物燃料電池加氨之實驗研究：電池性能與穩定性量測
★ 高溫高壓甲苯參考燃料層流與紊流燃燒速度量測及其正規化分析	★ 合成氣固態氧化物燃料電池添加二氧化碳之實驗研究：電池性能與穩定性量測

檔案

[Endnote RIS 格式]

[Bibtex 格式]

[相關文章]

[文章引用]

[完整記錄]

[館藏目錄]

[檢視]

[下載]

本電子論文使用權限為同意立即開放。
已達開放權限電子全文僅授權使用者為學術研究之目的，進行個人非營利性質之檢索、閱讀、列印。
請遵守中華民國著作權法之相關規定，切勿任意重製、散佈、改作、轉貼、播送，以免觸法。

摘要(中)

本論文有兩大重點：(1)研究預混紊流燃燒之火花引燃機制，即定量量測最小引燃能量(minimum ignition energy, MIE)、火核成長和火焰傳播；(2)探討加氫效應對MIE值及火焰傳播速度(flame propagation speed, SF)之影響。MIE值攸關氣爆、火災預防和燃料安全準則，並可直接應用於火花引燃(spark ignition, SI)引擎之設計和提昇引燃效率。本研究使用低碳燃料甲烷和空氣之預混燃氣，針對不同當量比(equivalence ratio) = 0.6 ~ 1.3，從層流到具極高強度之紊流場，從薄碎焰(flamelet)到散佈狀燃燒(distributed combustion)區域，進行一系列完整之MIE值定量量測，找出MIE值和正規化紊流強度 (u’’/SL)和Karlovitz (Ka)數之函數關係，其中u’’是方均根紊流擾動強度，SL為層流燃燒速度，Ka為一化學反應和紊流特性時間比，Ka = (u’’/SL)2(ReT)-0.5，紊流雷諾數ReT = u’’LI/nu，LI為紊流積分長度尺度而nu為反應物之運動黏滯係數。所有引燃實驗均在一大十字型預混紊流燃燒器執行，它配置一對由10匹馬力三相馬達驅動之特製反向旋轉風扇和空孔板，可產生一近似等向性紊流場，其u’’值可高達約8 m/s於中央均勻區，也是本實驗尖端電極所置放之處。使用高功率脈衝引燃系統和高速CMOS攝影機(每秒5000張，512 x 512 pixels)，進行MIE值定量量測和火核及火焰傳播影像之擷取。結果顯示，在任一固定φ值下，MIE值均會先隨u’’/SL增大而漸增，但當u’’/SL或Ka超過一臨界值時，原漸增之MIE值變為驟升，此一MIE值轉折(transition)，為一新發現。藉由比較MIE值轉折前之火焰影像，我們發現火焰由原本薄碎燄模式轉變為散佈狀模式。轉折發生時所對應之 u’’/SL值為16 ~ 27，而相對應之臨界Ka (Kac)均大於1且約在φ=1附近有一最小值，如Ka≒9, 7 和4.2 當φ= 0.6, 0.7 和0.8而Kac≒5 和2.2 當φ= 1.3和1.2，這顯示傳統Klimov和Williams規範(Kac ~ 1)需要作修正。有關加氫效應(φ = 0.6)，加入少量氫氣即可有效降低MIE值和增加SF，如在層流條件(u’’/SL = 0)，加氫量由0%增加至20%，MIE值會由2.14 mJ驟降至0.27 mJ。而當u’’/SL = 5.1，同樣0%到20%的加氫量，會使MIE值由3.7 mJ降至約0.313 mJ。加氫20%之SF會比無加氫時，快約42%。加氫效應在紊流條件下會更加明顯，如在u’’/SL = 5.13，同樣的加氫量，並使SF值增加了86%。是故加氫於貧油預混甲烷燃氣，不僅可有效降低貧油脂失效點火(misfire)機率並可提升SF。本研究成果可應用至SI引擎和燃氣渦輪機，並深具學術價值。

摘要(英)

This thesis has two objectives: (1) The study of spark ignition mechanism for premixed turbulent combustion via quantitative measurements of minimum ignition energy (MIE), kernel formation and growth, and subsequent flame propagation; (2) the study of the influence of hydrogen addition on MIE and flame propagation speed (SF). MIE is an extremely important parameter for atmospheric explosion, fire prevention, and fuel safety standards. MIE data can be directly applied to the design of the spark ignition (SI) engine and thus increase the ignition efficiency. This study uses low carbon fuel, methane (CH4) and air premixtures, at various equivalence ratios varying from 0.6 to 1.3. At each value of equivalence, a complete dataset of MIE is measured under both laminar and turbulent conditions covering different combustion modes from laminar to flamelet to distributed regimes. Thus, MIE curves as a function of normalized turbulence intensities (u’’/SL) and/or turbulence Karlovitz number (Ka) at various values of equivalence ratio can be established, where u’’, SL and Ka are root-mean-square turbulence intensity, laminar burning velocity and a time ratio of chemical reaction to turbulent defined as Ka = (u’’/SL)2(ReT)^-0.5. Here the turbulent Reynolds number ReT = u’’LI/nu, where LI and nu are the integral length scale and the kinematic viscosity of reactants. All ignition experiments are carried out in a large cruciform premixed turbulent combustor which is equipped with a pair of counter-rotating fans and perforated plates at each end of its horizontal vessel, capable of generating intense isotropic turbulence with values of u’’ up to 8 m/s in the central uniform region where the spark electrodes with needle ends are located. Using a high-power pulse ignition system with Pearson current and high-voltage probes, values of MIE can be measured. Furthermore, ignited kernel and subsequent flame propagation are recorded via a high-speed imaging system with 5000 frames/s and 512 x 512 pixels resolution. Results show that at any fixed values of equivalence ratio, there is a transition on values of MIE. Before the transition, values of MIE only increase gradually with increasing values of u’’/SL or Ka. Above the transition, MIE values increase abruptly. This transition is a new finding. By comparing radially-expanding flame front images before and after the transition, it is found that combustion modes may change from turbulent-flamelet to turbulent-distributed. The critical values of u’’/SL for the occurrence of transition are varying with different values of equivalence ratio ranging from 16 to 27, and their corresponding values of Kac are all greater than unity indicating the failure of Klimov & Williams’ criterion that predicted Kac = 1. The minimum value of Kac (> 1) is expected to occur near equivalence ratio = 1, since values of Kac are decreasing from both lean and rich sides. For examples, Kac ~ 9, 7 and 4.2 when equivalence ratio = 0.6, 0.7 and 0.8, while Kac ~ 5 and 2.2 when equivalence ratio = 1.3 and 1.2, respectively. When hydrogen is doped (equivalence ratio = 0.6), values of MIE and/or SF can be effectively decreasing and/or increasing. For instances, MIE values decrease from 2.14 mJ to 0.27 mJ in quiescent condition when the hydrogen addition increases from 0% to 20%, while under the same amount of hydrogen addition, MIE values decrease form 3.7 mJ to 0.313mJ when u’’/SL = 5.13. Similarly, values of SF with 20% hydrogen addition are about 42% higher than that of no hydrogen addition in quiescent conditions, but up to 86% increase is found when u’’/SL = 5.13. Therefore, the usage of hydrogen addition in lean premixed turbulent methane combustion not only decreases effectively the probability of misfire, but also increases values of SF significantly. These findings are important for fundamental understanding of premixed turbulent combustion and for practical applications to SI engines and gas turbines.

關鍵字(中)

★ 熄滅距離
★ 最小引燃能量
★ 火花引燃機制
★ 預混紊流燃燒
★ 加氫效應

關鍵字(英)

★ premix turbulent combustion
★ hydrogen addition effect
★ quenching distance
★ minimum ignition energy
★ spark ignition mechanisms

論文目次

摘　要 I
英文摘要 II
誌　謝 IV
目　錄 V
圖目錄 VIII
符號說明 XI
第一章前言 1
1.1 研究動機 1
1.2 問題所在 2
1.3 解決方案 3
1.4 論文架構 5
第二章文獻回顧 6
2.1 火核的形成與熄滅 6
2.2 影響MIE值的相關參數 7
2.2.1 預混燃氣當量比值 7
2.2.2 燃氣初始溫度與壓力 7
2.2.3 電極材料 8
2.2.4 電極直徑與幾何形狀 8
2.2.5 電極間距 10
2.2.6 化學反應流場型態 10
2.3 火焰傳播 11
2.3.1 紊流燃燒Huygen’s傳遞理論 11
2.3.2 預混紊流燃燒狀態圖(Phase Diagram) 12
2.4 加氫效應對MIE值與燃燒速度之影響 13
第三章實驗設備與量測方法 20
3.1 十字型預混紊流燃燒器 20
3.2 高功率脈衝引燃系統 21
3.3 火花放電能量與計算 21
3.4 影像擷取系統及火焰傳播速度分析方法 22
3.5 實驗流程 23
3.6 誤差分析 23
第四章結果與討論 28
4.1 不同流場之火焰傳播 28
4.2 靜態流場引燃機制 29
4.2.1 電極直徑與電極間距對MIE值之影響效應 29
4.2.2 引燃能量對火核形成與發展之影響 31
4.2.3 不同當量比值對火核形成與發展之影響 32
4.3 紊流流場引燃機制 32
4.3.1 層流火焰、薄碎火焰和散佈狀火焰 32
4.3.2 MIE值與f、u'/SL和Ka之關係 33
4.3.3 MIE值之轉折(Transition) 34
4.4 火焰傳播速度定量量測 35
4.5 加氫效應 36
第五章結論與未來工作 58
5.1 結論 58
5.2 未來工作 59
參考文獻 60

參考文獻

[1] The Department of Energy (DOE). http://www.doe.gov/
[2] Energy Information Administration, Annual Energy Outlook 2007 with Projections to 2030, Rep. No. DOE/EIA-0383 (2007).
[3] Huang, C. C., Shy, S. S., Liu, C. C. and Yan, Y. Y., “A Transition on Minimum Ignition Energy for Lean Turbulent Methane Combustion in Flamelet and Distributed Regimes,” Proc. Combust. Inst. 31, 1401-1409 (2006).
[4] Hoffert, M. I., Caldeira, K., Jain, A. K., Haites, E. F., Harveyk, L. D. D., Potter, S. D., Schlesinger, M. E., Schneider, S. H., WattsI, R. G., Wigley, T. M. L. and Wuebbles, D. J., “Energy Implications of Future Stabilization of Atmospheric CO2 Content,” Nature 395, 881-884 (1998).
[5] Correa, S., “Current Problems in Gas Turbine Combustion,” Fall Technical Meeting, The Combustion Institute, Eastern States Section, Dec. 3-5, Orlando, FL (1990).
[6] Shy, S. S., Lin, W. J. and Wei, J. C., “An Experimental Correlation of Turbulent Burning Velocities for Premixed Turbulent Methane-Air Combustion,” Proc. R. Soc. Lond. A 456, 1997-2019 (2000).
[7] Yang, S. I. and Shy, S. S., “Global Quenching of Premixed CH4/Air Flame: Effects of Turbulent Straining Equivalence Ratio, and Radiative Heat Loss,” Proc. Combust. Inst. 29, 1841-1847 (2002).
[8] Shy, S. S., Lee, E. I., Cheng, N. W. and Yang, S. I., “Direct and Indirect Measurements of Flame Surface Density, Orientation, and Curvature for Premixed Turbulent Combustion Modeling in a Cruciform Burner,” Proc. Combust. Inst. 28, 383-390 (2000).
[9] Ilbas, M., Crayford, A. P., Yılmaz, İ., Bowen, P. J. and Syred, N., “Laminar-Burning Velocities of Hydrogen-Air and Hydrogen-Methane-Air Mixtures: An Experimental Study,” Int. J. Hydrog. Energy 31, 1768-1779 (2006).
[10] Kido, H., Huang, S., Tanoue, K. and Nitta, T., “Improving the Combustion Performance of Lean Hydrocarbon Mixtures by Hydrogen Addition,” JSAE. Review 15, 165-170 (1994).
[11] Lewis, B. and von Elbe, G., Combustion, Flame and Explosions of Gases, 3rd Ed., Academic Press, London (1987).
[12] Kono, M., Niu, K., Tsukammoto, T. and Ujiie, Y., “Mechanism of Flame Formation Produced by Short Duration Sparks,” Proc. Combust. Inst. 22, 1643-1649 (1988).
[13] 黃朝祺，“貧油甲烷預混紊流燃燒最小引燃能量定量量測”，國立中央大學機械工程研究所，碩士論文，2006年。
[14] Scull, W. E., “Relation Between Inflammables and Ignition Sources in Aircraft Environments,” NACA TN-2227 (1951).
[15] Moorhouse, J., Williams, A. and Maddison, T. E., “An Investigation of the Minimum Ignition Energies of Some C1 to C7 Hydrocarbons,” Combust. Flame 23, 203-213 (1974).
[16] Ziegler, G. F. W., Wagner, E. P. and Maly, R. R., “Ignition of Lean Methane-Air Mixtures by High Pressure Glow and Arc Discharges,” Proc. Combust. Inst. 20, 1817-1824 (1984).
[17] Kono, M., Hatori, K. and Iinuma, K., “Investigation on Ignition Ability of Composite Sparks in Flowing Mixtures,” Proc. Combust. Inst. 20, 1643-1649 (1984).
[18] Kitagawa, T., Ogawa, T. and Nagano, Y., “The Effects of Pressure on Unstretched Laminar Burning Velocity, Markstein Length and Cellularity of Spherically Propagating Laminar Flames,” COMODIA, August 2-5, Japan (2004).
[19] Bradley, D., Haq, M. Z., Hicks, R. A., Kitagawa, T., Lawes, M., Sheppard, C. G. W. and Woolley, R., “Turbulent Burning Velocity, Burned Gas Distribution, and Associated Flame Surface Definition,” Combust. Flame 133, 415-430 (2003).
[20] Bradley, D., Gaskell, P. H. and Gu, X. J., “Burning Velocities, Markstein Lengths, and Flame Quenching for Spherical Methane-Air Flame: A Computational Study,” Combust. Flame 104, 176-198 (1996).
[21] Damköhler, G., “The Effect of Turbulent on the Flame Velocity in Gas Mixtures,” Z. Elektrchem. 46, 601-652 (1940). (English translation NASA Tech. Mem. 1112, 1947).
[22] Borghi, R., “On the Structure and Morphology of Turbulent Premixed Flames,” Recent Advances in the Aerospace Sciences, Ed. C. Casci, 117-138, New York, Plenum (1985).
[23] Bray, K. N. C., “Turbulent Flows with Premixed Reactants,” Turbulent Reacting Flows, Eds. Libby, P. A. & Williams, F. A., 115-183, New York, Springer-Verlag (1980).
[24] Peters, N., “Laminar Flamelet Concepts in Turbulent Combustion,” Proc. Combust. Inst. 21, 1231-1250 (1986).
[25] Williams, F. A., Combustion Theory, 2nd Ed., Addison-Wesley, Redwood City (1985).
[26] Peters, N., Turbulent Combustion, Cambridge University Press, Cambridge (2000).
[27] Huang, Z., Zhang, Y., Zeng, K., Liu, B., Wang, Q. and Jiang, D., “Measurements of Laminar Burning Velocities for Natural Gas-Hydrogen-Air Mixtures,” Combust. Flame 146, 302-311 (2006).
[28] 林文基，“甲烷與丙烷預混紊流燃燒速度的量測”，國立中央大學機械工程研究所，碩士論文，1999年。
[29] Shy, S. S., I, W. K. and Lin, M. L., “A New Cruciform Burner and its Turbulence Measurements for Premixed Turbulent Combustion Study,” Exp. Thermal Fluid Sci. 20, 105-114 (2000).
[30] Glassman, I., Combustion, 3rd Ed., Academic Press, San Diego (1996).
[31] Vagelopoulos, C. M., Egolfopoulos, F. N. and Law, C. K., “Further Considerations on the Determination of Laminar Flame Speeds with the Counterflow Twin-Flame Technique,” Proc. Combust. Inst. 25, 1341-1347 (1994).

指導教授

施聖洋(Shenq-yang Shy)

審核日期

2007-7-23

推文