臺灣博碩士論文加值系統

為因應化石能源短缺與溫室氣體減量之壓力，本研究探討甲烷/氨氣混合燃料燃燒、熄滅與NOx生成排放之特性，利用數值計算程式OPPDIF，搭配窄頻輻射模型及化學反應機制，計算甲烷/氨氣相向噴流擴散火焰，分析甲烷與氨氣混合燃料之組成比例及火焰拉伸率，對火焰結構、火焰最高溫度、NOx之生成與排放的影響，同時比較不同氨氣燃燒之化學反應機制在NOx反應路徑的差異。研究結果顯示，GRI 3.0與Okafor反應機制的火焰結構相似，但在使用GRI 3.0時，NO最大莫耳分率與NO淨產生率，隨著NH3的添加而增加，而使用Okafor反應機制時，在NH3添加一定量之後，NO最大莫耳分率與NO淨產生率就接近平緩，並低於GRI 3.0的計算結果，此外隨著NH3比例的增加，其差異更加明顯，這是由於Okafor有較詳盡的NH3化學反應式。由NO反應路徑圖可看出Okafor多了有關於NH3、NH2、NH之間的還原路徑及N2H2的反應路徑，使得NH2、NH的產生量較少，此外Okafor還刪除了NH+H2O<=>HNO+H2此一反應式，以降低HNO intermediate route的NO產生率，但增加了NH+O<=>NO+H的Fuel-NOx的生成。除此之外，隨著NH3添加量的上升，與NO相關之主要反應路徑的反應率皆上升，其中以HNO intermediate route、N2O intermediate route較為明顯，另外在Okafor的NO反應路徑中，NNH intermediate route也較為明顯，但Prompt route則下降。

In order to cope with the pressure of fossil energy shortage and greenhouse gas reduction, this study explores combustion, extinction, and NOx emission characteristics of methane/ammonia blended fuels. The numerical calculation program OPPDIF, combined with a narrow-band radiation model and detailed chemical reaction mechanism, is used to calculate the methane/ammonia opposed-jet diffusion flames. The effects of the fuel compositions and flame strain rates on the flame structures, the maximum flame temperatures, and the NOx emissions of the methane/ammonia blended fuels are analyzed. Different chemical reaction mechanisms on ammonia combustion are compared and two reaction mechanisms are applied to demonstrate NOx reaction pathways. The research results show that the flame structures from GRI 3.0 and Okafor reaction mechanisms are similar, but the maximum NO mole fraction and the NO production rate with GRI 3.0 increases with the increase of NH3 percentages. With Okafor mechanism, the maximum NO mole fraction and NO production rate are leveled out after adding a certain amount of ammonia and the values are lower than those predicted by GRI 3.0. In addition, the differences are more obvious with the increase of ammonia, because Okafor mechanism has a more detailed NH3 chemical reaction steps. It can be seen from the NO reaction pathways that Okafor has included more NO reduction reactions among NH3, NH2, and NH, and the reactions involving N2H2, so that the amounts of NH2 and NH produced are less. Okafor also neglects the reaction of NH + H2O <=> HNO + H2 to reduce the NO production through HNO intermediate route, but increasing the Fuel-NOx production from NH + O <=> NO + H. Moreover, with the increase in the amount of NH3, the reaction rates of the main NO reaction routes have increased, including HNO intermediate route and N2O intermediate route, which are more evident. For Okafor’s mechanism, the NO production through NNH intermediate route is also more enhanced while decreased through Prompt route.

目錄

指導教授推薦書
口試委員會審定書
致謝 iii
中文摘要 iv
Abstract vi
目 錄 viii
圖目錄 xi
表目錄 xvi
第一章、 緒論 1
1.1 研究背景 1
1.2 文獻回顧 4
1.3 研究目標 6
第二章、理論方法 8
2.1 火焰架構 8
2.2 相向噴流擴散火焰統御方程式 10
2.3 窄頻輻射模型 17
2.4化學反應機制 23
第三章、數值方法 26
3.1 擴散火焰數值方法 26
3.2 執行程序 27
第四章、結果與討論 29
4.1 CH4/NH3燃燒反應機制的比較 30
4.1.1 不同反應機制的可燃極限 30
4.1.2 不同反應機制的NOx排放 30
4.2 拉伸率對火焰結構的影響 33
4.2.1 甲烷的火焰結構 33
4.2.2 甲烷的NOx排放 36
4.3 添加氨氣對甲烷燃燒與NO排放之影響 39
4.3.1 甲烷與氨氣混合的火焰結構 39
4.3.2 甲烷與氨氣混合的NOx排放 47
4.4 NO反應路徑(Reaction Pathways) 52
4.4.1純甲烷之NO反應路徑 55
4.4.2加入氨氣之NO反應路徑 56
第五章、結論 87
第六章、參考文獻 89
附錄一、GRI Mech 3.0 化學反應機制 96
附錄二、Okafor 化學反應機制 114
附錄三、Okafor修正GRI Mech 3.0反應機制比較表 134


圖目錄


圖2-1、相向噴流預混火焰示意圖 9
圖2-2、相向噴流擴散火焰示意圖 9
圖2-3、軸對稱相向噴流擴散火焰架構 11
圖2-4，Tsuji的逆流擴散火焰轉直角坐標系圖 12
圖2-5，軸向速度與燃料端距離關係圖 12
圖2-6，水的吸收率與波長關係圖 17
圖4-1、不同化學反應機制在100%甲烷下的火焰最高溫度與拉伸率關係圖 31
圖4-2、不同化學機制於不同氨氣比例添加下在拉伸率100 (s-1)的火焰最高溫度與NO的排放關係圖 31
圖4-3、100%甲烷在拉伸率2 (s-1)下的火焰結構 34
圖4-4、100%甲烷在拉伸率10 (s-1)下的火焰結構 34
圖4-5、100%甲烷在拉伸率100 (s-1)下的火焰結構 35
圖4-6、100%甲烷在拉伸率200 (s-1)下的火焰結構 35
圖4-7、100%甲烷在拉伸率300 (s-1)下的火焰結構 36
圖4-8、100%甲烷的NO莫耳分率分佈與拉伸率之關係 37
圖4-9、100%甲烷的NO2莫耳分率分佈與拉伸率之關係 37
圖4-10、100%甲烷火焰溫度及NO排放與拉伸率之關係 38
圖4-11、拉伸率10 (s-1)，CH4 80%/NH3 20% 下的火焰結構 40
圖4-12、拉伸率10 (s-1)，CH4 60%/NH3 40% 下的火焰結構 40
圖4-13、拉伸率10 (s-1)，CH4 40%/NH3 60% 下的火焰結構 41
圖4-14、拉伸率10 (s-1)，CH4 20%/NH3 80% 下的火焰結構 41
圖4-15、拉伸率10 (s-1)，CH4 0%/NH3 100% 下的火焰結構 42
圖4-16、拉伸率100 (s-1)，CH4 90%/NH3 10% 下的火焰結構 43
圖4-17、拉伸率100 (s-1)，CH4 80%/NH3 20% 下的火焰結構 44
圖4-18、拉伸率100 (s-1)，CH4 60%/NH3 40% 下的火焰結構 44
圖4-19、拉伸率200 (s-1)，CH4 90%/NH3 10% 下的火焰結構 46
圖4-20、拉伸率200 (s-1)，CH4 80%/NH3 20% 下的火焰結構 46
圖4-21、CH4/NH3混合燃料之火焰拉伸率與最大NH3添加量關係圖 47
圖4-22、拉伸率10 (s-1)下不同NH3添加量的最高火焰溫度與最大NO莫耳分率關係圖 49
圖4-24、拉伸率100 (s-1)下不同NH3添加量的最高火焰溫度與最大NO莫耳分率關係圖 50
圖4-25、拉伸率100(s-1)下不同NH3添加量的最高火焰溫度與NO淨產生率關係圖 50
圖4-26、拉伸率200 (s-1) 下不同NH3添加量的最高火焰溫度與最大NO莫耳濃度關係圖 51
圖4-27、拉伸率200 (s-1) 下不同NH3添加量的最高火焰溫度與NO淨產生率關係圖 51
圖4-28、CH4 100%/NH3 0%於中拉伸率100 (s-1)之NO反應路徑(GRI 3.0) 61
圖4-29、CH4 100%/NH3 0%於中拉伸率100 (s-1)之NO反應路徑(Okafor) 62
圖4-30、CH4 80%/NH3 20%於中拉伸率100 (s-1)之NO反應路徑(GRI 3.0) 63
圖4-31、CH4 80%/NH3 20%於中拉伸率100 (s-1)之NO反應路徑(Okafor) 64
圖4-32、CH4 80%/NH3 20%於中拉伸率10 (s-1)之NO反應路徑(GRI 3.0) 67
圖4-33、CH4 80%/NH3 20%於中拉伸率10 (s-1)之NO反應路徑(Okafor) 68
圖4-34、CH4 80%/NH3 20%於低拉伸率200 (s-1)之NO反應路徑(GRI 3.0) 69
圖4-35、CH4 80%/NH3 20%於低拉伸率200 (s-1)之NO反應路徑(Okafor) 70
圖4-36、CH4 80%/NH3 20%在不同拉伸率下的主要路徑與NO淨生率疊層圖(GRI 3.0) 71
圖4-37、CH4 80%/NH3 20%在不同拉伸率下的主要路徑與NO淨生率疊層圖(Okafor) 71
圖4-38、CH4 80%/NH3 20%在高拉伸率 200 (s-1)，主要反應式的NO生成率 (GRI 3.0紅色/Okafor藍色) 72
圖4-39、CH4 80%/NH3 20%在中拉伸率 100 (s-1)，主要反應式的NO生成率 (GRI 3.0紅色/Okafor藍色) 73
圖4-40、CH4 80%/NH3 20%在低拉伸率 10 (s-1)，主要反應式的NO生成率 (GRI 3.0紅色/Okafor藍色) 74
圖4-41、CH4 20%/NH3 80%於低拉伸率10 (s-1)之NO反應路徑(GRI 3.0) 79
圖4-42、CH4 20%/NH3 80%於低拉伸率10 (s-1)之NO反應路徑(Okafor) 80
圖4-43、不同NH3比例在10 (s-1)下的主要路徑與NO淨生率疊層圖(GRI 3.0) 81
圖4-44、不同NH3比例再10 (s-1)下的主要路徑與NO淨生率疊層圖(Okafor) 81
圖4-45、CH420%/NH380%在低拉伸率 10 (s-1)，主要反應式的NO生成率 (GRI 3.0紅色/Okafor藍色) 82
圖4-46、CH4 60%/NH3 40%於高拉伸率100 (s-1)之NO反應路徑(GRI 3.0) 83
圖4-47、CH4 60%/NH3 40%於高拉伸率100 (s-1)之NO反應路徑(Okafor) 84
圖4-48、不同NH3比例在100 (s-1)下的主要路徑與NO淨生率疊層圖(GRI 3.0) 85
圖4-49、不同NH3比例在100 (s-1)下的主要路徑與NO淨生率疊層圖(Okafor) 85
圖4-50、CH4 60%/NH3 40%在中拉伸率 100 (s-1)，主要反應式的NO生成率 (GRI 3.0紅色/Okafor藍色) 86

表目錄
表 一、常見燃料之燃燒基本特性 2
表二、S8高斯基分法，各方向的方向餘弦與積分權重值 22
表 三、反應路徑分析之條件(拉伸率與NH3添加量) 52

[1] United Nations Framework Convention on Climate Change (UNFCCC). Paris agreement, [cited 2018 January 02]. Available from::http://unfccc.int/paris_agreement/items/9444.php.
[2] Maggio G, Cacciola G. When will oil, natural gas, and coal peak? Fuel 98 (2012) 111-123.
[3] National Hydrogen Vision Meeting, US, Department of Energy, Washington, DC(2001)Nov. 15-16.
[4] Law CK, Kwon OC. Effects of hydrocarbon substitution on atmospheric hydrogen-air flame propagation. Int J Hydrogen Energy 29 (2004) 867-79.
[5] Thomas G, Parks G. Potential roles of ammonia in a hydrogen economy e a study of issues related to the use ammonia for on-board vehicular hydrogen storage, [cited 2014 December 08]. Available from:: http://www.hydrogen. energy.gov/pdfs/nh3_paper.pdf.
[6] Zamfirescu C, Dincer I. Using ammonia as a sustainable fuel. J Power Sources 185 (2008) 459-65.
[7] Bomelburg HJ. Use of ammonia in energy-related applications, Plant/Operations Progress1(3) (1982) 175-180.
[8] Brandhorst H, Baltazar-Lopez M, Tatarchuk B, Cahela DR, Barron T. Ammonia its transformation and effective utilization, 6th International energy conversion engineering conference, Cleveland, Ohio (2008) 1-11.
[9] Morch CS, Bjerre A, Gottrup MP. Sorenson SC, Schramm J. Ammonia/hydrogen mixtures in an SI-engine: engine performance and analysis of a proposed fuel system, Fuel 90 (2011) 854-864.
[10] Grannell S M, Assanis DN, Bohac SV, Gillespie DE. The fuel mix limits and efficiency of a stoichiometric, ammonia, and gasoline duel fueled spark ignition engine. J. Eng. Gas Turbines Power 130 (2008) 042802.
[11] Reiter AJ., Kong SC. Combustion and emissions characteristics of compression-ignition engine using dual ammonia-diesel fuel. Fuel 90 (2011) 87-97.
[12] Gross CW, Kong SC. Performance characteristics of a compression-ignition engine using direct-injection ammonia-DME mixtures. Fuel 103 (2013) 1069-1079.
[13] Kurata O, Iki N, Matsunuma T, Inoue T, Tsujimura T, Furutani H, Kobayashi H, Hayakawa A. Performances and Emission Characteristics of NH3-air and NH3-CH4-air Combustion Gas-turbine Power Generations, Proc. Combust. Inst., 36 (2017) 3351-3359.
[14] Reiter AJ, Kong SC. Demonstration of compression-ignition engine combustion using ammonia in reducing greenhouse gas emissions. Energy Fuels 22 (2008) 2963-2971.
[15] Shan L, Shanshan Z, Hua Z, Zhuyin R. Analysis of air-staged combustion of NH3/CH4 mixture with low NOx emission at gas turbine conditions in model combustors. Fuel 237 (2019) 50-59
[16] Peters N. Laminar diffusion flamelet models in non-premixed turbulent combustion. Progress in Energy and Combustion Science 10 (1984) 319-339.
[17] Dixon-Lewis G, Missaghi M. Structure and extinction limits of counterflow diffusion flames of hydrogen-nitrogen mixtures in air. Symposium (International) on Combustion 22 (1988) 1461-1470.
[18] Shih HY. Computed extinction limits and flame structures of H2/O2 counterflow diffusion flames with CO2 dilution. International Journal of Hydrogen Energy 34 (2009) 4005-4013.
[19] Jae WK, Sun C, Hee KK, Seungro Lee, Oh CK. Extinction limits and structure of counterflow nonpremixed methane-ammonia/air flames. Energy 165 (2018) 314-325.
[20] Gas Research Institute, available from:http://www.me.berkeley.edu/gri_ mech/.
[21] Miller J, Bowman CT. Mechanism and modeling of nitrogen chemistry in combustion, Progress in Energy and Combustion Science 15 (1989) 287-338.
[22] Lindstedt RP, Lockwood FC, Selim M A. Detailed kinetic modelling of chemistry and temperature effects on ammonia oxidation, Combustion Science and Technology 99 (1994) 253-76.
[23] Konnov AA. Implementation of the NCN pathway of prompt-NO formation in the detailed reaction mechanism, Combustion and Flame 156 (2009) 2093-2105.
[24] Tian Z, Li Y, Zhang L. Glarborg, P., Qi, F., An experimental and kinetic modeling study of premixed NH3/CH4/O2/Ar flames at low pressure, Combustion and Flame 156 (2009) 1413-1426.
[25] Mathieu O, Petersen EL. Experimental and modeling study on the high temperature oxidation of Ammonia and related NOx chemistry, Combustion and Flame 162 (2015) 554-570.
[26] Hua X, Agustin VM, Richard M, Philip JB. Numerical study assessing various ammonia/methane reaction models for use under gas turbine conditions. Fuel 196 (2017) 344-351.
[27] Okafor EC, Naito Y, Colson S, Ichikawa A, Kudo T, Hayakawa A, Kobayashi H. Measurement and modelling of the laminar burning velocity of methane-ammonia-air flames at high pressures using a reduced reaction mechanism. Combustion and Flame 204 (2019) 162-175.
[28] Okafor EC, Naito Y, Colson S, Ichikawa A, Kudo T, Hayakawa A, Kobayashi H. Experimental and numerical study of the laminar burning velocity of CH4–NH3–air premixed flames. Combustion and Flame 187 (2018) 185-198.
[29] Mitchell DS, Vincent G. Formulation of the premixed and non-premixed test problems. Lecture Notes in Physics (1911).
[30] Tsuji H. Counterflow diffusion flames. Progress in Energy and Combustion Science 8 (1982) 93-119.
[31] Ravikrishna RV, Sahu AB. Advances in understanding combustion phenomena using non-premixed and partially premixed counterflow flames: A review. International Journal of Spray and Combustion Dynamics 10 (2018) 38-71.
[32]Water Absorption Spectrum from:http://www1.lsbu.ac.uk/water/vibrat.html.
[33]Malkmus W. Random Lorentz band model with exponential-tailed S-1 line –intensity distribution function, Journal of Optical Socity 57 (1967) 323-329
[34]Yu Y, Masuya G, Ronney PD. Proceedongs of the Combustion Institute 27 (1998) 2619-2626.
[35] Ludwing CB, Malkmus W, Reardon JE, Thomson JAL. Handbook of infrared radiation from combustion gases. (1997).
[36] Yu S, Hamid H, Jakob MC, Chun Z, Paul M, Peter G. Ammonia oxidation at high pressure and intermediate temperatures.Fuel 181 (2016) 358-365.
[37] Junichiro O, Mitsuo K, Teruo M, Hiroshi I, Koichi Y. Chemical kinetic modeling of ammonia oxidation with improved reaction mechanism for ammonia/air and ammonia/hydrogen/air combustion. International Journal of Hydrogen Energy 43 (2018) 3004-3014.
[38] Klippenstein SJ., Harding LB, Glarborg P, Miller JA. The role of NNH in NO formation and control. Combustion and Flame 158 (2011) 774-789.
[39] Kéromnès A, Metcalfe WK, Heufer KA, Donoho H, Das AK, Sung CJ, Herzler J, Naumann C, Griebel P, Methieu O, Krejci, Petersen EL, Petersen EL, Pitz WJ, Curran HJ. An experimental and detailed chemical kinetic modeling study of hydrogen and syngas mixture oxidation at elevated pressures. Combustion and Flame 160 (2013) 995-1011.
[40] Dagaut P, Glarborg P, Alzueta MU. The oxidation of hydrogen cyanide and related chemistry. Progress in Energy and Combustion Science 34 (2008) 1-46.
[41] Dayma G, Dagaut P. Effects of air contamination on the combustion of hydrogen-effect of NO and NO2 addition on hydrogen ignition and oxidation kinetics. Combustion Science and Technology 178 (2006) 1999-2024.
[42] Sivaramakrishnan R, Brezinsky K, Dayma G, Dagaut P. High pressure effects on the mutual sensitization of the oxidation of NO and CH4-C2H6 blends. Physical Chemistry Chemical Physics 9 (2007) 4230-4244.
[43] Glarborg, P, Alzueta, MU, Dam-Johansen K, Miller JA. Kinetic modeling of hydrocarbon/nitric oxide interactions in a flow reactor. Combustion and Flame 115 (1998) 1-27.
[44] Rasmussen CL, Geest Jakobsen JON, Glarborg, P. Experimental measurements and kinetic modeling of CH4/O2 and CH4/C2H6/O2 conversion at high pressure. International Journal of Chemical Kinetics 40 (2008) 778-807.
[45] Skreiberg Ø, Kilpinen P, Glarborg P. Ammonia chemistry below 1400 K under fuel-rich conditions in a flow reactor. Combustion and Flame 136 (2004) 501-518.
[46] Dagaut P, Glarborg P, Alzueta MU. The oxidation of hydrogen cyanide and related chemistry. Progress in Energy and Combustion Science 34 (2008) 1-46.
[47] Rasmussen CL, Rasmussen AE, Glarborg P. Sensitizing effects of NOx on CH4 oxidation at high pressure. Combustion and Flame Volume 154, (2008) 529-545.
[48] Lutz AE, Kee JR, Grcar JF, Rulple FM. Oppdif: a fortran program for computing opposed-flow diffusion flames, Sandia National Laboratories Report SAND96-8243, 1996.
[49] Grcar JF. The Twopnt program for boundary value problems, Sandia Naional Laboratories Report SAND91-8230, 1992.
[50] Kee RJ, Rupey FM, Miller JA. Chemkin II: a fortan chemical kinetics package for the analysis of gas-phase chemical kinetics, Sandia National Laboratories Report SAND89-8009, 1989.
[51] Kee RJ, Dixon-Lewis G, Warnatz JA, Coltrin ME, Miller JA. Fortran computer code package for the evaluation of gas-phase multi-componet transport properties, Sandia National Laboratories Report SAND86-8246, 1986.
[52] da Rocha RC, Costa M, Bai X. Chemical kinetic modelling of ammonia/hydrogen/air ignition, premixed flame propagation and NO emission. Fuel 246 (2019) 24-33.
[53] Okafor EC, Naito Y, Colson S, Ichikawa A, Kudo T, Hayakawa A, Kobayashi H. Measurement and modelling of the laminar burning velocity of methane-ammonia-air flames at high pressures using a reduced reaction mechanism. Combustion and Flame 204 (2019) 162-175.