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Extinction characteristics of premixed flames of typical hydrogen-rich fuel gas |
| ZOU Jun, LI Zhaoxing, ZHANG Hai, Lü Junfu, ZHANG Yang |
| Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China |
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Abstract [Objective] Adaptability of fuel is an essential design requirement of advanced gas turbines. Hydrogen-rich fuel gas can be obtained from a variety of sources, and its use will be an important part of the future development of gas turbines. When using gas turbine combustion technology to burn hydrogen-rich fuel, if the flame goes out, it will lead to unsafe equipment. As a result, the extinction of turbulent hydrogen-rich fuel flame is the key problem when we design gas turbine combustors. [Methods] In this study, the optimized experimental approach and numerical simulation method of counterflow flame are used to compare the extinction strain rate of two typical hydrogen-rich fuel gases under laminar and turbulent combustion conditions, and the main reasons for the difference were examined. Two typical hydrogen-rich fuel gases used in this study are called FA and FB in this paper. As far as FA is concerned, the CO component ratio of fuel is higher, the dilution ratio is lower, and the calorific value is significantly higher. FA can be considered as the typical hydrogen-rich synthetic gas obtained from entrained flow coal gasification, and FB can be regarded as the typical hydrogen-rich synthetic gas obtained from fluidized bed coal gasification, both of which have certain representative significance. The upper nozzle of the counterflow flame produces nitrogen, while the lower nozzle produces premixed fuel with varying equivalence ratios. The equivalence ratio covers a range of 0.4-1.0. The gas temperature at the nozzle outlet is 300 K. The particle image velocimetry (PIV) system is used to obtain the velocity information of the flow field at the nozzle outlet. The turbulent transport model is added to the OPPDIF code for numerical simulation. [Results] The results demonstrated that, within the range of working conditions studied, the numerical simulation method used in this paper could well predict the extinction strain rate of laminar and turbulent flames. The difference between experimental and simulation results was less than ±10% for a laminar counterflow flame and ±40% for a turbulent counterflow flame. Due to the instability of the turbulent flow field, the measurement of the extinction strain rate fluctuated greatly during the turbulent combustion experiment, and the error bar was greater than that of the laminar combustion experiment. [Conclusions] Under laminar combustion conditions, hydrogen-rich fuel gas with a higher mole fraction of active radicals such as H, O, and OH in the flame front has a higher reaction rate and heat release rate of key chemical reactions, so it can resist higher flame stretching deformation. With the increase of the equivalence ratio, the extinction strain rate indicates an upward trend. Turbulence not only improves the mixing of active groups and reactants, thereby improving the reaction, which increases the rate of key chemical reactions and heat release in the reaction area, but it also improves heat transfer of the flame from inside to outside, resulting in a lower internal temperature of the flame.
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| Keywords
hydrogen-rich combustion
premixed flame
counterflow flame
extinction strain rate
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Issue Date: 22 April 2023
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[1] KOTHARI R, BUDDHI D, SAWHNEY R L. Comparison of environmental and economic aspects of various hydrogen production methods[J]. Renewable and Sustainable Energy Reviews, 2008, 12(2):553-563.
[2] 李克忠,张荣,毕继诚.煤和生物质共气化制备富氢气体的实验研究[J].燃料化学学报, 2010, 38(6):660-665. LI K Z, ZHANG R, BI J C. Experimental study on hydrogen-rich gas production by co-gasification of coal and biomass in a fluidized bed[J]. Journal of Fuel Chemistry and Technology, 2010, 38(6):660-665.(in Chinese)
[3] 李苏辉,张归华,吴玉新.面向未来燃气轮机的先进燃烧技术综述[J].清华大学学报(自然科学版), 2021, 61(12):1423-1437. LI S H, ZHANG G H, WU Y X. Advanced combustion technologies for future gas turbines[J]. Journal of Tsinghua University (Science and Technology), 2021, 61(12):1423-1437.(in Chinese)
[4] LIU H Y, QIAN W K, ZHU M, et al. Kinetics modeling on NOx emissions of a syngas turbine combustor using rich-burn, quick-mix, lean-burn combustion method[J]. Journal of Engineering for Gas Turbines and Power, 2020, 142(2):021005.
[5] GLARBORG P. Detailed kinetic mechanisms of pollutant formation in combustion processes[J]. Computer Aided Chemical Engineering, 2019, 45:603-645.
[6] WILLIAMS F A. Combustion theory[M]. Menlo Park, USA:Benjamin Cummings, 1985.
[7] 高聚忠.煤气化技术的应用与发展[J].洁净煤技术, 2013, 19(1):65-71. GAO J Z. Application and development of coal gasification technologies[J]. Clean Coal Technology, 2013, 19(1):65-71.(in Chinese)
[8] PETERS N. Turbulent combustion[M]. Cambridge, UK:Cambridge University Press, 2000.
[9] MARUTA K, YOSHIDA M, JU Y G, et al. Experimental study on methane-air premixed flame extinction at small stretch rates in microgravity[J]. Symposium (International) on Combustion, 1996, 26(1):1283-1289.
[10] YANG X H, WU Y X, ZHANG Y, et al. Reassessing the 2-D velocity boundary effect on the determination of extinction stretch rate and laminar flame speed using the counterflow flame configuration[J]. Combustion and Flame, 2021, 234:111630.
[11] VAGELOPOULOS C M, EGOLFOPOULOS F N. Laminar flame speeds and extinction strain rates of mixtures of carbon monoxide with hydrogen, methane, and air[J]. Symposium (International) on Combustion, 1994, 25(1):1317-1323.
[12] SABELNIKOV V A, YU R, LIPATNIKOV A N. Thin reaction zones in highly turbulent medium[J]. International Journal of Heat and Mass Transfer, 2019, 128:1201-1205.
[13] REN Z Y, YANG H T, LU T F. Effects of small-scale turbulence on NOx formation in premixed flame fronts[J]. Fuel, 2014, 115:241-247.
[14] KITAJIMA A, UEDA T, MATSUO A, et al. Experimental investigation of the flame structure and extinction of turbulent counterflow non-premixed flames[J]. Symposium (International) on Combustion, 1996, 26(1):137-143.
[15] CORITON B, FRANK J H, GOMEZ A. Effects of strain rate, turbulence, reactant stoichiometry and heat losses on the interaction of turbulent premixed flames with stoichiometric counterflowing combustion products[J]. Combustion and Flame, 2013, 160(11):2442-2456.
[16] MIZOBUCHI Y, HIRAKAWA K. One-dimensional H2/O2 counterflow diffusion flame simulation for flamelet table construction at supercritical pressure[J]. Transactions of the Japan Society for Aeronautical and Space Sciences, 2013, 56(5):239-252.
[17] ZHANG H, FAN R, WANG S F, et al. Extinction of lean near-limit methane/air flames at elevated pressures under normal-and reduced-gravity[J]. Proceedings of the Combustion Institute, 2011, 33(1):1171-1178.
[18] LEE E, CHOI C, HUH K Y. Application of the coherent flamelet model to counterflow turbulent premixed combustion and extinction[J]. Combustion Science and Technology, 1998, 138(1-6):1-25.
[19] LUTZ A E, KEE R J, GRCAR J F, et al. OPPDIF:A Fortran program for computing opposed-flow diffusion flames[R]. Livermore, USA:Sandia National Laboratories, 1997.
[20] 邹俊,杨协和,张扬,等.小尺度湍流对近极限非预混火焰熄灭极限的影响[J].燃烧科学与技术, 2022, 28(2):190-197. ZOU J, YANG X H, ZHANG Y, et al. Effect of small-scale turbulence on extinction limit of near-limit non-premixed flames[J]. Journal of Combustion Science and Technology, 2022, 28(2):190-197.(in Chinese)
[21] POPE S B. Turbulent flows[M]. Cambridge, UK:Cambridge University Press, 2000.
[22] KOLLA H, SWAMINATHAN N. Strained flamelets for turbulent premixed flames II:Laboratory flame results[J]. Combustion and Flame, 2010, 157(7):1274-1289.
[23] POPE S B. PDF methods for turbulent reactive flows[J]. Progress in Energy and Combustion Science, 1985, 11(2):119-192.
[24] KEE R J, RUPLY F M, MILLER J A. Chemkin-II:A Fortran chemical kinetics package for the analysis of gas-phase chemical kinetics[R]. Livermore, USA:Sandia National Laboratories, 1989.
[25] KEE R J, DIXON-LEWIS G, WARNATZ J, et al. A Fortran computer codepackage for the evaluation of gas-phase, multicomponent transport properties[R]. Livermore, USA:Sandia National Laboratories, 1986.
[26] EGOLFOPOULOS F N. Geometric and radiation effects on steady and unsteady strained laminar flames[J]. Symposium (International) on Combustion, 1994, 25(1):1375-1381.
[27] SMITH G P, TAO Y, WANG H.Foundational Fuel Chemistry Model Version 1.0[DB/OL].(2016-01-01)[2022-10-30]. http://nanoenergy.Stanford.edu/ffcm1.
[28] TANG Y, ZHUO J K, CUI W, et al. Non-premixed flame dynamics excited by flow fluctuations generated from dielectric barrier discharge plasma[J]. Combustion and Flame, 2019, 204:58-67. |
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2023,
Vol. 63
