預混焰和紊流尾流交互作用：拉伸率與輻射熱損失效應量測

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：162

、訪客IP：3.145.156.250

姓名

廖展興(Jan-Shing Lian) 查詢紙本館藏

畢業系所

機械工程學系

論文名稱

預混焰和紊流尾流交互作用：拉伸率與輻射熱損失效應量測
(premixed turbulent wake interaction)

相關論文

★ 蚶線形滑轉板轉子引擎設計與實作	★ 實驗分析預混紊焰表面密度傳輸方程式及Bray-Moss-Libby模式
★ 低紊流強度預混焰之傳播及高紊流強度預混焰之熄滅	★ 預混火焰與尾流交相干涉之實驗研究
★ 自由傳播預混焰與紊流尾流交互作用﹔火焰拉伸率和燃燒速率之量測	★ 重粒子於泰勒庫頁提流場之偏好濃度與下沈速度實驗研究
★ 潔淨能源：高效率天然氣加氫燃燒技術與污染排放物定量量測	★ 預混焰與紊流尾流交互作用時非定常應變率、曲率和膨脹率之定量量測
★ 實驗方式產生之均勻等向性紊流場及其於兩相流之應用	★ 液態紊流噴流動能消散率場與微尺度間歇性之定量量測
★ 四維質點影像測速技術與微尺度紊流定量量測	★ 潔淨能源:超焓燃燒器研發
★ 小型熱再循環觸媒燃燒器之實驗研究及應用	★ 預混紊流燃燒：碎形特性、當量比和輻射熱損失效應
★ 預混甲烷紊焰拉伸量測，應用高速PIV	★ 氫能利用：過焓觸媒熱電產生器之實作研究

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)

本論文探討輻射熱損失對預混層焰拉伸率之影響，利用本實驗室已研發的紊流尾流直立式燃燒器(高度為1.5 m、截面積為15 × 15 cm2)及數位質點影像測速儀(digital particle image velocimetry, DPIV)，定量量測反應流場之空氣動力應變率、曲率、拉伸率與膨脹率。實驗一開始先將燃燒器抽真空，之後將已預混之燃氣灌入，使爐內壓力增至常壓，於燃燒器上方引燃產生由上往下的自由傳播預混層焰，同時燃燒器頂端原密封的頂板會打開，使得引燃時所產生的膨脹氣體可排出，避免壓力效應之影響。當往下自由傳播預混層焰到達燃燒器中間附近之水平置放抽板上方2公分時，抽板開始往左迅速移動產生一紊流尾流。我們使用高速雷射斷層攝影術和DPIV技術，來擷取紊流尾流與自由傳播預混層焰交相干涉之二維影像和獲得熱流場速度場，經統計分析後，可得到反應流場之空氣動力應變率、曲率、拉伸率與膨脹率等等參數之資訊。
為了研究輻射熱損失對於預混甲烷-空氣層焰拉伸率的影響，我們以(1)不加任何稀釋氣體、(2)加氮氣與(3)加二氧化碳於預混燃氣內來改變輻射熱損失程度的大小，上述三種情況都可找到當流場之負應變率增加，其正膨脹率會增加的結果，而當正應變率提高，則負膨脹率會增加，上述結果不受輻射熱損失效應的影響。由機率密度函數(probability density function, PDF)分布圖中觀察到，在富油甲烷-空氣的實驗中，其空氣應變率值在+200 s-1及-100 s-1區間中變化，而在富油甲烷-空氣-氮氣的實驗和富油甲烷-空氣-二氧化碳的實驗中，其空氣應變率值在 50 s-1區間中變化，所以空氣應變率會受到輻射熱損失之增加而降低。拉伸率為曲率項和空氣應變率項所相加而成，而輻射熱損失效應會明顯降低空氣應變率值，但輻射熱損失效應對曲率值的影響不大，再則因拉伸率受曲率項之影響較應變率項為大，故整體而言，輻射熱損失對富油甲烷火焰之拉伸率的影響甚小，幾乎可忽略不計。比較富油甲烷-空氣-氮氣和富油甲烷-空氣-二氧化碳之膨脹率，發現增加輻射熱損失的強度會降低反應流場的膨脹率（即火焰之燃燒強度）。由小波分析(wavelet analysis)方法，發現富油甲烷火焰受壓縮應變渦對和擴張應變渦對的影響，流場積分尺度會隨著時間增加而減少，顯示非定常(unsteady)效應對預混紊焰有影響，將於本論文中探討分析。

摘要(英)

This thesis investigates experimentally effect of radiative heat losses on the stretch rate of a premixed flame interacting with a decaying turbulent wake. The decaying turbulent wake was generated by quickly withdrawing a horizontal plate in a long vertical burner with 1.5m height and with a cross-sectional area of 15×15 cm2. Before a run, the burner is evacuated and then filled up methane-air mixtures with or without diluents to 1 atm, including N2 and CO2, at a given equivalence ratio ( ). A run begins by ignition at the top of the burner where the top plate with 15×15 cm2 cross-sectional area is simultaneously opened in order to release the gas from thermal expansion and generate a downward-propagating premixed flame at 1 atm. When the flame propagates 1m downwardly, very near to the top of the horizontal plate, the horizontal plate is quickly withdrawn to create a turbulent wake for flame-wake interactions. We use high-speed digital particle imaging velocimetry to measure flame-wake interactions, so that the corresponding dilatation rate, aerodynamic strain rate, curvature, and thus the stretching rate can be obtained.
Three cases of rich methane/air premixed flames at 1.4 or 1.45 are studied, including the pure methane/air case ( 1.45; negligible radiative heat loss), the N2-dilulent case ( 1.4; small radiative heat loss), and the CO2-diluent case ( 1.4; large radiative heat loss). It is found that the negative strain rate increases the positive dilatation rate, while the positive strain rate increases the negative dilatation rate. This correlation is the same among these three cases, regardless different degrees of radiative heat loss. The effect of radiative heat loss reduces the magnitude of the strain rate, but it has little influence on the curvature. It is found that the curvature term plays a more dominate role on the stretch rate than the strain rate term. When the dilatation rate of the CH4/air/N2 case is compared with that of the CH4/air/CO2 case, it is found that increasing the degree of radiative heat loss corresponds to a decrease of the dilatation rate, indicating the dilatation rate may be used as an indication of flame burning strength, as suggested by Driscoll and his co-workers (1996).Using the wavelet analysis, the integral length scale of flame-wake interactions among these three cases are obtained. Finally, the unsteady effect of flame-wake interactions will be also discussed.

關鍵字(中)

★ 輻射熱損失

關鍵字(英)

★ radiative heat loss

論文目次

摘要................................................................................................................... I
英文摘要........................................................................................................ .II
誌謝...................................................................................................III
目錄.................................................................................................................IV
圖表目錄.......................................................................................................VI
符號說明.......................................................................................................XI
第一章前言..................................................................................................1
1.1 動機.................................................................................................... 1
1.2 問題所在............................................................................................1
1.3 解決提案............................................................................................3
1.4 論文架構............................................................................................3
第二章文獻回顧........................................................................................ 5
2.1 預混紊流燃燒區域圖……………….....................................….......5
2.2 非定常拉伸效應………………………………………..……....…..8
2.2.1質熱擴散不穩定性……………………………………………8
2.2.2拉伸的基本定義………………………………………………9
2.3輻射熱損失對於火焰拉伸率的影響..............................…….........12
第三章實驗設備和量測分析方法................................…...…............20
3.1 紊流尾流燃燒設備..................................................……..........…... 20
3.2 紊流尾流之產生...............................................................…............23
3.3 影像處理說明...........................................................…………....... 23
3.4 DPIV速度場量測.......…................................….......................…....24
3.5空氣應變率、曲率、拉伸率和膨脹率之分析法.............................25
第四章結果與討論....................................................................................31
4.1預混焰與紊流尾流交相干涉過程….....…….……...........................31
4.2非定常渦度與膨脹率之分析...….....…....................…...............…..32
4.3非定常拉伸率、應變率、曲率與膨脹率之分析..............…........... 34
4.4非定常拉伸率、應變率、曲率與膨脹率之機率密度函數分布…..37
4.5輻射熱損失之非定常膨脹率與空氣應變率之分析..........................40
4.6壓力效應和wavelet分析....................................................................41
第五章結論與未來工作............................................................................70
5.1 結論.....................................................................................................70
5.2 未來工作.............................................................................................72
參考文獻.........................................................................................................73

參考文獻

Aung, K. T., Hassan, M. I., and Faeth, G. M., ”Flame Stretch Interactions of Laminar Premixed Hydrogen/Air Flames at Normal Temperature and Pressure”, Combust. Flame, Vol. 109, pp. 1-24 (1997).
Choi, C. W., and Puri, I. K., “Contribution of Curvature to Flame-Stretch Effects on Premixed Flames”, Combust. Flame, Vol. 126, pp. 1640-1654 (2001).
Chen, J. H., and Hong G. IM, “Preferential Diffusion Effects on the Burning Rate of Interacting Turbulent Premixed Hydrogen-Air Flames”, Combust. Flame, Vol. 131, pp.246-258 (2002).
Driscoll, J. F., and Roberts, W. L., “A Laminar Vortex Interacting with a Premixed Flame: Measured Formation of Pockets of Reactants”, Combust. Flame, Vol. 87, pp.245-256 (1991).
Driscoll, J. F., and Roberts, WM. L., “OH Fluorescence Images of The Quenching of a Premixed Flame During an Interaction With a Vortex”, Twenty-sixth Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 169-176 (1996).
Driscoll, J. F., Sinibaldi, J. O., Mueller, C. J., and Donbar, J. M., “Propagation Speeds and Stretch rates measured along wrinkled flames to assess the theory of flame stretch”, Combust. Flame, Vol. 133, pp.323-334 (2003).
Echekki, T., and Chen, J. H., “Unsteady Strain Rate and Curvature Effects in Turbulent Premixed Methane-Air Flames”, Combust. Flame, Vol. 106, pp. 184-202 (1996).
Frank, J. H., Kalt, P. A. M., and Bilger, R. W., “Measurements of Conditional Velocities in Turbulent Premixed Flames by Simultaneous OH PLIF and PIV”, Combust. Flame, Vol. 116, pp. 220-232 (1999).
Hassan, M. I., Aung, K. T., and Faeth, G. M., “Measured and Predicted Properties of Laminar Premixed Methane/Air Flames at Various Pressures”, Combust. Flame, Vol. 115, pp. 539-550 (1998).
Lee, J. G., Lee, T. W., Nye, D. A., and Santavicca, D. A.., “Lewis Number Effects on Premixed Flames Interacting with Turbulent Kármán Vortex Streets”, Combust. Flame, Vol. 100, pp. 161-168 (1995).
Law, C. K., “Dynamics of Stretched Flames”, Twenty-two Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 1381-1402 (1988).
Mantel, T., and Samaniego, J. M., “Fundamental Mechanisms in Premixed Turbulent Flame Propagation via Vortex-Flame Interactions Part Ⅱ: Numerical Simulation”, Combust. Flame, Vol. 118, pp. 557-582 (1999).
Mueller, C. J., Driscoll, J. F., Reuss, D. L., and Drake, M. C., “Effects of Unsteady Stretch on the Strength of a Freely-Propagating Flame Wrinkled By a Vortex”, Twenty-sixth Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 347-355 (1996).
Mueller, C. J., Driscoll, J. F., Sutkus, D. J., Roberts, W. L., Drake, M. C. and Smooke, M. D., “Effect of Unsteady Stretch Rate on OH Chemistry during a Flame-Vortex Interaction: To Assess Flamelet Models”, Combust. Flame, Vol. 100, pp. 323-331 (1995).
Najm, H. N., Paul, P. H., Mueller, C. J., and Wyckoff, P. S., “On the Adequacy of Certain Experimental Observables as Measurements of Flame Burning Rate”, Combust. Flame, Vol. 113, pp. 312-332 (1998).
Rqrtveit, G. J., & Hustad, J. E., “Effects of Diluents on NOX Formation in Hydrogen Counterflow Flames”, Combust. Flame, Vol. 130, pp. 48-61 (2002).
Stone, R., and Clarke, A., “Correlation for the Laminar-Burning Velocity of Methane/Diluent/Air Mixtures Obtained in Free-Fall Experiments” Combust. Flame, Vol. 114, pp. 546-555 (1998).
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., Vol. 29, pp.1841-1847 (2002).
黎文孝 “預混火焰與尾流交相干涉之實驗研究”，國立中央大學機械工程研究所，碩士論文(2000)。
蘇瑞期 “自由傳播預混焰與紊流尾流交互作用：火焰拉伸率和燃燒速率之量測”，國立中央大學機械工程研究所，碩士論文(2001)。
李志杰 “非定常應變率、曲率和膨脹率定量量測在預混焰與紊流尾流交互作用時”，國立中央大學機械工程研究所，碩士論文(2002)。

指導教授

施聖洋(Shenqyang Shy)

審核日期

2003-7-15

推文