臺灣博碩士論文加值系統

本研究利用穩態三維反應流場模擬擴散式穩定燃燒器經過縮尺後之火焰特性，分別比較固定速度、固定停滯時間、固定熱釋放率與固定動量(又稱為固定雷諾數)四種燃燒器尺度變換方法，將穩定燃燒器進行縮尺。研究中同時使用一漩流式穩定燃燒器來與擴散式燃燒器做比較，分別以焦爐氣(COG)及天然氣(NG)為燃料操作下之火焰型態與與燃燒特性之差異。研究中燃燒器於縮尺前後輸出熱值分別為146 kW及116 kW對應之燃料COG流率分別為480 Nm3/hr及380 Nm3/hr；NG流量則分別為209 Nm3/hr 及165 Nm3/hr，故流量比為0.79。由模擬結果顯示，在尺度縮小後之擴散式穩定燃燒器與漩流式燃燒器皆能穩定操作COG與NG，且產生高溫區位置亦達到穩定燃燒器操作需求。由結果中可以看出固定動量燃燒器壁面上會有較高之熱通量產生，而發現本研究中所使用之擴散式穩定燃燒器之內環與外環空氣間距，應為操作時關鍵設計參數，其距離會影響燃燒器出口壁面上之迴流區。

In this study, flame characteristics of stable burners scaled down through (1)fixed velocity, (2)fixed residence time, (3)fixed volumetric heat release rate, and (4)fixed momentum (fixed Reynolds Number) approaches were numerically investigated. Combustion characteristics of the scaled-down burners were benchmarked with a swirl-type burner, and compare with the flame characteristics when using coke oven gas (COG) and natural gas (NG). The thermal loadings of the original and the scaled-down burners are 146 kW and 116 kW, respectively. The corresponding fuel flow rate when using coke oven gas are 480 Nm3/hr and 380 Nm3/hr, while the flow rates of fuel when operating with natural gas are 209 Nm3/hr and 165 Nm3/hr. The scaling flow ratio is 0.79. The results show that stable flames are obtained with all four burners studied under both COG and NG operations. Fixed momentum burner has larger heat flux on burner’s wall. It shows the distance of air inner diameter and air outer diameter is the key parameters for designing a scaled-down burner since it affects the formation of recirculation zones in the near-burner region.

摘要 i
Abstract ii
誌謝 iii
目錄 iv
表目錄 vii
圖目錄 viii
符號說明 xv
第1章 緒論 1
1-1 前言 1
1-2 文獻回顧 1
燃燒器穩焰機制 1
尺度變換方法 3
噴流擴散焰火焰長度經驗公式 8
1-3 研究目的 10
1-4 本文架構 12
第2章 燃燒器縮尺及模擬方法 13
2-1 燃燒器縮尺方法 13
2-2 焦爐氣(COG)與天然氣(NG)基礎火焰特性 16
噴流火焰長度計算 16
化學平衡分析 18
一維預混焰分析 21
2-3 統御方程式與數值模型 26
2-4 數值方法 32
2-5 計算網格與網格獨立性測試 33
第3章 不同次模型之比較 45
3-1 速度分佈 46
3-2溫度與熱焓分佈 48
3-3濃度分佈 50
3-4燃燒腔壁面熱通量分佈 54
第4章 縮尺燃燒器之焦爐氣(COG)火焰特性 56
4-1 COG模擬設定 56
4-2 速度場分佈 58
3-3 溫度場與熱焓分佈 60
4-4 濃度分佈 63
4-5 燃燒腔壁面熱通量分佈 68
4-6 火焰型態比較 71
4-7 小結 74
第5章 不同縮尺比操作焦爐氣(COG)火焰特性 77
5-1 速度分佈 77
5-2 溫度分佈 81
5-3 濃度分佈 85
5-4 燃燒腔壁面熱通量分佈 98
5-5 火焰型態比較 102
5-6 小結 108
第6章 縮尺燃燒器之天然氣(NG)火焰特性 110
6-1 NG模擬設定 110
6-2 速度場分佈 111
6-3 溫度場與熱焓分佈 113
6-4 濃度分佈 116
6-5 燃燒腔壁面熱通量分佈 121
6-6 火焰型態比較 122
6-7小結 124
第7章 總結 126
7-1 結論 126
7-2 未來展望 127
參考文獻 129
附錄A 固態粒子與壁面交互作用模型 133

[1]D.B. Spalding, H.C. Hottel, S.L. Bragg, A.H. Lefebvre, D.G. Shepherd, and A.C. Scurlock (1963), The Art of Partial Modeling, Symposium (International) on Combustion 9(1), 833-843.

[2]J.M. Beer and N.A. Chigier, Combustion Aerodynamics (Chapter 7), Wiley Press, 1972.

[3]S.R. Turns, An Introduction to Combustion: Concepts ＆ Applications 2nd ed., McGraw-Hill, 1999.

[4]M.D. Durbin, M.D. Vangsness, D.R. Ballal, and V.R. Katta (1996), Study of Flame Stability in a Step Swirl Combustor, Journal of Engineering for Gas Turbines and Power 118(2), 308-315.

[5]R. Weber (1996), Scaling Characteristics of Aerodynamics, Heat Transfer, and Pollutant Emissions in Industrial Flame, Symposium (International) on Combustion 26(2), 3343-3354.

[6]J.P. Smart, D.J. Morgan, and P.A. Roberts (1992), The Effect of Scale on the Performance of Swirl Stabilized Pulverized Coal Burners, Symposium (International) on Combustion 24(1), 1365-1372.

[7]J.P. Smart and D.J. Morgan (1994), Exploring the Effects of Employing Different Scaling Criteria on Swirl Stabilized Pulverized Coal Burner Performance, Combustion Science and Technology 100, 331-343.

[8]R. Weber and F. Breussin (1998), Scaling Properties of Swirling Pulverized Coal Flames: from 180 kW to 50 MW Thermal Input, Symposium (International) on Combustion 27(2), 2957-2964.

[9]T.C.A. Hsieh, W.J.A. Dahm, and J.F. Driscoll (1998), Scaling Laws for NOx Emission Performance of Burners and Furnace from 30 kW to 12 MW, Combustion and Flame 114, 54-80.

[10]J.A. Cole, T.P. Parr, N.C. Widmer, K.J. Wilson, K.C. Schadow, and W.M.R. Seeker (2000), Scaling Criteria for the Development of an Acoustically Stabilized Dump Combustor, Proceedings of the Combustion Institute 28(1), 1297-1304.

[11]M. Sadakata and Y. Hirose (1994), Scaling Law for Pollutant Emission from a Combustion Furnace, Fuel 73(8), 1338-1342.

[12]A.D. Al-Fawaz, L.M. Dearden, J.T. Hedley, M. Missaghi, M. Pourkashanian, A. Williams, and L.T. Yap (1994), NOx Formation in Geometrically Scaled Gas-Fired Industrial Burner, Symposium (International) on Combustion 25(1), 1027-1034.

[13]R.K. Cheng, D.T. Yegian, M.M. Miyasato, G.S. Samuelsen, C.E. Benson, R. Pellizzari, and P. Loftus (2000), Scaling and Development of Low-Swirl Burners for Low-Emission Furnace and Boilers, Proceedings of the Combustion Institute 28, 1305-1313.

[14]F.P. Ricou and D.B. Spalding (1961), Measurements of Entrainment by Axisymmetrical Turbulent Jets, Journal of Fluid Mechanics 11, 21-32.

[15]W.R. Hawthorne, D.S. Weddell, and H.C. Hottel (1948), Mixing and Combustion in Turbulent Gas Jets, Proceedings of the Combustion Institute 3(1), 266-288.

[16]S. Kumar, P.J. Paul, and H.S. Mukunda (2005), Investigations of the Scaling Criteria for a Mild Combustion Burner, Proceedings of the Combustion Institute 30(2), 2613-2621.

[17]S. Yon, J-C Sautet, and T. Boushaki (2012), Effects of Burned Gas Recirculation on NOx Emissions from Natural Gas-Hydrogen-Oxygen Flames in a Burner with Separated Jets, Energy ＆ Fuels 26(8), 4703-4711.

[18]H.A. Becker, D. Liang, and Visible (1978), Length of Vertical Free Turbulent Diffusion Flames, Combustion and Flame 32, 115-137.

[19]M.A. Delichatsios (1993), Transition from Momentum to Buoyancy-Controlled Turbulent Jet Diffusion Flames and Flame Height Relationships, Combustion and Flame 92(4), 349-364.

[20]R.W. Bilger (1976), Turbulent Jet Diffusion Flames, Progress in Energy and Combustion Science 1, 87-109.

[21]M. Kim, J. Oh, and Y. Yoon (2011), Flame Length Scaling in a Non-premixed Turbulent Diluted Hydrogen Jet with Coaxial Air, Fuel 90(8), 2624-2629.

[22]H. Eickhoff (1982), Turbulent Hydrocarbon Jet Flames, Progress in Energy and Combustion Science 8(2), 159-169.

[23]G. Heskestad (1999), Turbulent Jet Diffusion Flames: Consolidation of Flame Height Data, Combustion and Flame 118(1-2), 51-60.

[24]B.J. McBride, and M.S. Gordon (1996), Computer Program for Calculation of Complex Chemical Equilibrium Compositions and Applications II. User's Manual and Program Description.
Available: http://www.grc.nasa.gov/WWW/CEAWeb/RP-1311P2.htm

[25]B.J. McBride and M.S. Gordon (1996), Computer Program for Calculation of Complex Chemical Equilibrium Compositions and Applications I. Analysis.
Available: http://www.grc.nasa.gov/WWW/CEAWeb/RP-1311.htm

[26]D. Goodwin, CANTERA: An Object-Oriented Software Toolkit for Chemical Kinetics, Thermodynamics, and Transport Processes, Caltech, Pasadena, 2009.
Available: http://code.google.com/p/cantera
G.P. Smith, D.M. Golden, M. Frenklach, N.W. Moriarty, B. Eiteneer, M. Goldenberg, C.T. Bowman, R.K. Hanson, S. Song, W.C. Gardiner, Jr., V.V. Lissianski, and Z. Qin. Available: http://www.me.berkeley.edu/gri_mech/

[27]ANSYS Fluent Release 13.0 User Guide, ANSYS, Inc., 2010.

[28]ANSYS Fluent Release 13.0 Theory Guide, ANSYS, Inc., 2010

[29]V. Yakhot, and S.A. Orszag (1986), Renormalization Group Analysis of Turbulence. I. Basic Theory, J. Scientfic Computing 1, 1-51.

[30]V. Yakhot, S.A. Orszag, S. Thangam, T.B. Gatski, and C.G. Speziale (1992), Development of Turbulence Models for Shear Flows by a Double Expansion Technique, Phys Fluid A-Fluid 4, 1510-1520.

[31]W. Rodi, Influence of Buoyancy and Rotation on Equations for the Turbulent Length Scale, 2nd Symposium on Turbulent Shear Flows, London, England, July 2-4, 1979.


[32]D.L. Baulch, D.D. Drysdall, D.G. Horne, and A.C. Lloyd, Evaluated Kinetic Data for High Temperature Reactions, Butterworth, 1973.

[33]S.V. Patankar, and D.B. Spalding (1972), A Calculation Procedure for Heat, Mass and Momentum Transfer in Three-Dimensional Parabolic Flows, International Journal of Heat and Mass Transfer 15(10), 1787-1806.

[34]D.C. Wilcox, Turbulence Modeling for CFD 1st ed., DCW Industries, Inc., 1998.

[35]W.P. Jones, and R.P. Lindstedt (1988), Global Reaction Schemes for Hydrocarbon Combustion, Combustion and Flame 73(3), 233-249.

[36]B.F. Magnussen, and B.H. Hjertager (1977), On Mathematical Modeling of Turbulent Combustion with Special Emphasis on Soot Formation and Combustion, Symposium (International) on Combustion 16(1), 719-729.