本研究之目的乃利用火焰自然螢光發展低成本、無雷射之光學感測系統，利用點量測的方式取代面量測，以瞭解火焰內部化學交互作用與各成份濃度及參數之影響，將來亦可作發展為大型燃燒器對於污染物生成之即時監控系統的依據。
本論文以卡塞格倫(Cassegrain)反射鏡聚焦與光纖連結收集傳輸火焰自然螢光，再以307.3 ± 11nm、432.1 ± 5nm和516.3 ± 4.nm光學濾鏡分光，利用被動方式以光電倍增管(photomultiplier tube, PMT)診測預混甲烷層流噴流火焰燃燒於當量比0.85至1.7間，火焰中電子能階達激發態之OH*、CH*以及C2*成份粒子產生的自然螢光強度分佈。
經由量測與估算，卡塞格倫反射鏡之焦點解析可達40m × 600m（徑向×軸向）微米級之精度。同時以噴流火焰出口上方3mm和9mm兩高度之螢光變化作為比較之依據。其結果除能以OH*、CH*螢光強度位置顯示火焰前緣(flamefront)外，亦可由C2*螢光強度證實雙碳基之反應生成隨流場愈下游愈顯著的火焰化學反應現象。再以螢光強度隨當量變化觀察，得知OH*於當量0.9左右反應最為強烈，CH*於當量1.1處，C2*則是於濃燃燒1.25時為最。就化學螢光強度比值而言，在Φ＜1.35時，CH* /OH*隨當量比呈現線性關係，C2* /OH*、C2*/CH*同時也隨當量變化具有相依性。CH* /OH*亦與當量比倒數具線性關係，這些線性相依關係可以用為以火焰自然螢光量測火焰燃燒特性研究的數據資料庫。

The objective of this study is to develop a low cost, non-laser based optical system by using flame chemiluminescences to “pointwisely” analyze the local flame and chemical reaction characteristics. In addition, the developed optical system can be applied to monitor combustion process and pollutant formation in industrial furnaces and burners.
In this thesis, chemiluminescence measurements are performed to study the flame structure and characteristics of a laminar premixed methane/air jet flame operated over equivalence ratio 0.85 to 1.7. A Cassegrain-based optical system connected with fiber optics is used to collect, focus and transmit the emit lights from flame chemiluminescence, and the lights are then filtered by 307.3 ± 11nm(OH*), 432.1 ± 5nm(CH*) and 516.3 ± 4.nm(C2*) three narrowband-pass filters. The local chemiluminescence intensity of excited OH*, CH* and C2* species are measured by three photomultiplier tubes in a passive manner.
The results demostrate that the spatial resolution in terms of the focal point of the current Cassegrain system is 40 m in diameter and 600 m in length. The chemiluminescences intensities are scanned over two heights, 3mm and 9mm, from the burner exit. From the chemiluminescence results, one can easily identify the flame front locations from the OH* and CH* distributions, and one can observe the chemical phenomenon of recombination of mono-C species into bi-C species in the downstream region of the flame from the C2* distribution results. The OH* intensity peaks toward lean at equivalence ratio 0.9, the CH* peaks at 1.1, and the C2* peaks at 1.25 in the rich flame. In methane flames of equivalence ratio Φ＜1.35, CH* /OH* ratio has a linear relation with the equivalence ratio. At the same time, C2* /OH* and C2*/CH* ratios also has monotonic trends with Φ. Finally, CH* /OH* ratio is linear with the inverse of the equivalence ratio when the equivalence ratio is high. These linear relations of flame chemiluminescence ratio and local flame equivalence ratio can further be used as the data base for the research of combustion characteristics in the flames.

1. Bureau of Energy, Ministry of Economic Affairs, 2004, Energy White Paper.
http://www.moeaec.gov.tw/ecw.asp
2. Docquier, N. and Candel, S., 2002, "Combustion control and sensors: a review", Progress in Energy and Combustion Science, 28: p. 107-150.
3. Higgins, B., Mcquay, M. Q., Lacas, F. and Candel, S., 2001, "An experimental study on the effect of pressure and strain rate on CH chemiluminescence of premixed fuel-lean methane/air flames", Fuel, 80: p. 1583-1591.
4. Hardalupas, Y., Orain, M., Panoutsos, C. S., Taylor, A. M. K. P., Olofsson, J., Seyfried, H., Richter, M., Hult, J., Alden, M., Hermann, F. and Klingmann, J., 2004, "Chemiluminescence sensor for local equivalence ratio of reacting mixtures of fuel and air (FLAMESEEK)", Applied thermal engineering, 24: p. 1619-1632.
5. Jeong, Y. K., Jeon, C. H. and Chang, Y. J., 2006, "Evaluation of the equivalence ratio of the reacting mixture using intensity ratio of chemiluminescence in laminar partially premixed CH4-air flames", Experimental Thermal and Fluid Science, 30: p. 663-673.
6. Chou, T. and Patterson, D. J., 1995, "In-cylinder measurement of mixture mal-distribution in a L-head engine", Combustion and Flame, 101(1-2): p. 45-57.
7. Lawn, C. J., 2000, "Distributions of instantaneous heat release by the cross-correlation of chemiluminescent emissions", Combustion and Flame, 123(1-2): p. 227-240.
8. Blevins, L. G. and Gore, J. P., 1999, "Computed structure of low strain rate partially premixed CH4/air counterflow flames: implications for NO formation", Combustion and Flame, 116(4): p. 546-556.
9. Blevins, L. G., Renfro, M. W., Lyle, K. H., Laurendeau, N. M. and Gore, J. P., 1999, "Experimental study of temperature and CH radical location in partially premixed CH4/air coflow flames", Combustion and Flame, 118(4): p. 684-696.
10. Hardalupas, Y. and Orain, M., 2004, "Local measurements of the time-dependent heat release rate and equivalence ratio using chemiluminescent emission from a flame", combustion and flame, 139: p. 188-207.
11. Higgins, B., Mcquay, M. Q., Lacas, F., Rolon, J. C., Darabiha, N. and Candel, S., 2001, "Systematic measurements of OH chemiluminescence for fuel-lean, high-pressure, premixed, laminar flames", Fuel, 80: p. 67-74.
12. Kojima, J., Ikeda, Y. and Nakajima, T., 2000, "Spatially resolved measurement of OH*, CH*, and C2* chemiluminescence in the reaction zone of laminar methane/air premixed flames", Proceedings of the Combustion Institute, 28: p. 1757-1764.
13. Akamatsu, F., Wakabayashi, T., Tsushima, S., Katsuki, M., Mizutani, Y., Ikeda, Y., Kawahara, N. and Najajima, T., 1999, "The development of a light-collecting probe with high spatial resolution applicable to randomly fluctuating combustion fields", Meas. Sci. Technol. 10: p. 1240-1246.
14. Aleiferis, P. G., Hardalupas, Y., Taylor, A. M. K. P. and Urata, K. I. A. Y., 2004, "Flame chemiluminescence studies of cyclic combustion variations and air-to-fuel ratio of the reacting mixture in a lean-burn stratified-charge spark-ignition engine", Combustion and Flame, 136(1-2): p. 72-90.
15. Kojima, J., Ikeda, Y. and Nakajima, T., 2005, "Basic aspects of OH*, CH* ,C2* chemiluminescence in the reaction zone of laminar methane-air premixed flames", combustion and flame, 140: p. 34-45.
16. Ikeda, Y. and Zimmer, L., "Measurement of combustion fluctuations in turbulent premixed methane/air burner and high pressure oil burner", Proceedings of the 3rd Symposium on smart control of turbulence: p. 55-68.
17. Ikeda, Y., Kojima, J., Nakajima, T., Akamatsu, F. and Katsuki, M., 2000, "Measurement of the local flamefront structure of turbulent premixed flames by local chemiluminescence", Proceedings of the Combustion Institute, 28: p. 343-355.
18. Kojima, J., Ikeda, Y. and Nakajima, T., 2003, "Multi-point time-series observation of optical emissions for flame-front motion analysis", Meas. Sci. Technol. 14, 14: p. 1714-1724.
19. Leo, M. D., Saveliev, A., Kennedy, L. A. and Zelepouga, S. A., 2007, "OH and CH luminescence in opposed flow methane oxy-flames", Combustion and Flame, 149(4): p. 435-447.
20. Jeng, J. L., Li, Y. Y., Yang, S. Y. and Chen, W. H., 2007, "Simultaneous CH* and C2* chemiluminescence spatial measurement of Bunsen flame structure", Energy & Combustion.
21. K.K. Kuo, PRINCIPLES OF COMBUSTION, Chaper5, Wiley-Interscience, 1986