基于微火焰燃烧的新型低氮燃烧器模拟优化Optimization simulation of anovel low NOx burner based on micro flame combustion
宋佳霖,程星星,孙荣峰,王志强,耿文广,张兴宇,赵改菊,员冬玲,王鲁元
SONG Jialin,CHENG Xingxing,SUN Rongfeng,WANG Zhiqiang,GENG Wenguang,ZHANG Xingyu,ZHAO Gaiju,YUAN Dongling,WANG Luyuan
摘要(Abstract):
为应对大气污染严重问题,我国近年来加速了"煤改气"政策的推行,燃煤锅炉逐渐被燃气锅炉替代,开发和设计新型低氮燃气燃烧器具有重要意义。为响应国家"低氮环保"号召,提出了一种新型微火焰燃气低氮燃烧器。采用数值模拟方法对该燃烧器进行了相应的孔径结构优化,并在此基础上进行燃烧工况模拟,以选出燃烧的最优工况。结果表明:随着空气入口口径由16 mm增大到22 mm,由于口径增大,空气流速变慢,燃气甲烷与空气混合反应燃烧时间变长,燃烧释放出更多热量,继续增大口径时,由于小火焰具有更大的散热面积,热量向四周散失,故火焰中心高温区温度先升高后降低,而燃烧器燃烧原料为清洁燃料甲烷,生成NO_x主要为受温度影响较大的热力型NO_x,故NO_x生成量亦先升后降;随着过量空气由1.1增大到1.4,火焰中心高温区明显变小,温度也由2 270 K降低到2 042 K,由于炉膛内高温区温度降低且空气在高温区停留时间变短,NO_x生成量也由412 mg/m~3降低到52 mg/m~3。因此该新型低氮燃烧器燃烧效果良好,能有效降低NO_x排放。在甲烷入口口径设计为2 mm,空气入口口径设计为16 mm,过量空气系数设置为1.4时,该新型低氮燃烧器可以达到很低的NO_x排放量。
In response to solve serious problems of air pollution,China has accelerated the implementation of the " coal-to-gas" policy in recent years. Coal-fired boilers have been gradually replaced by gas-fired boilers. It is important to develop and design the new low-nitrogen gas burners. In response to the national call of " low nitrogen and environment protection",a new micro flame low nitrogen burner was proposed. Numerical simulation method was used to optimize the corresponding aperture structure of the burners,and on this basis,the combustion conditions were simulated to select the optimal combustion conditions. The results show that as the air inlet diameter increases from 16 mm to 22 mm,the air flow rate slows down due to the diameter increase,the combustion time of the mixed reaction of gas methane and air becomes longer,and the combustion releases more heat. When the diameter continues to increase,because the small flame has a larger heat dissipation area and the heat is dissipated to the surroundings,the temperature in the high-temperature area at the center of the flame first increases and then decreases. The burner burns clean fuel methane,and the produced NO_x is mainly thermal NO_x that is greatly affected by temperature. Therefore,the amount of NO_x generated first rises and then falls. With the increase of excess air from 1.1 to 1.4,the high temperature area in the center of theflame obviously decreases,the temperature also decreases from 2 270 K to 2 042 K. As the temperature in the high temperature zone in the furnace decreases and the residence time of air in the high temperature zone becomes shorter,the production of NO_x decreases from 412 mg/m~3 to 52 mg/m~3. In conclusion,the new low nitrogen burner has a good combustion effect and can effectively reduce NO_x emission. Moreover,when the methane inlet diameter is designed to be 2 mm,the air inlet diameter is designed to be 16 mm,and the excess air coefficient is set to be 1.4,the new low-nitrogen burner can achieve low NO_x emission.
关键词(KeyWords):
微火焰低氮燃烧器;数值模拟;天然气;过量空气系数;NO_x
micro flame low nitrogen burners;numerical simulation;methane;excess air coefficient;NO_x
基金项目(Foundation): 国家自然科学基金青年基金资助项目(51906130);; 济南市高校20条引进高端人才项目(2018GXRC032);; 山东省科学院国际合作项目(2019GHPY03);; 山东省能源碳减排技术与资源化利用重点实验室开放课题资助项目(ECRRU201804)
作者(Author):
宋佳霖,程星星,孙荣峰,王志强,耿文广,张兴宇,赵改菊,员冬玲,王鲁元
SONG Jialin,CHENG Xingxing,SUN Rongfeng,WANG Zhiqiang,GENG Wenguang,ZHANG Xingyu,ZHAO Gaiju,YUAN Dongling,WANG Luyuan
DOI: 10.13226/j.issn.1006-6772.IF20072201
参考文献(References):
- [1]回胜.旋流燃天然气燃烧器燃烧特性实验研究[D].哈尔滨:哈尔滨工业大学,2015.HUI Sheng.Experimental investigation on combustion charactics of swirling natural gas burner[D].Harbin:Harbin Institute of Technology,2015.
- [2]李萍.预混燃烧数值模拟与结构改进[J].工业加热,2008,37(2):33-36.LI Ping.Numerical simulation of premixed flow combustion and structure improvement[J].Industrial Heating,2008,37 (2):33-36.
- [3]郭甲生.预混燃烧混合器流动特性研究[J].工业加热,2008,37(6):51-53.GUO Jiasheng.The research of mixer flow characteristics used in premixed combustion[J].Industrial Heating,2008,37(6):51-53.
- [4]刘全清.燃气预混燃烧系统的优化设计与调试[J].工业加热,1999,28(6):22-26.LIU Quanqing.The optimal design and test of gas premixing combusting system[J].Industrial Heating,1999,28(6):22-26.
- [5]曾强.烟气再循环对燃气非预混燃烧NOx排放特性的影响[D].重庆:重庆大学,2018.ZENG Qiang.Effect of flue gas recirculation on NOxemissions characteristics of gas non-premixed combustion[D].Chongqing:Chongqing University,2018
- [6]宋少鹏.基于烟气再循环的工业锅炉天然气低氮燃烧研究[D].北京:清华大学,2016.SONG Shaopeng.Research on natural gas low NOxcombustion based on the flue gas recirculation for industrial boiler[D].Beijing:Tsinghua University,2016.
- [7]葛宏达.贫燃预混旋流燃烧的火焰特性与吹熄不稳定性[D].大连:大连理工大学,2019.GE Hongda.Flame characteristics and blow-out instability of leanpremixed swirl combustion[D].Dalian:Dalian University of Technology,2019.
- [8]李文锋,姬海民,申冀康,等.分级旋流耦合超低氮燃气燃烧器排放特性研究[J].热力发电,2019,48(6):65-70.LI Wenfeng,JI Haimin,SHEN Jikang,et al.Pollutant emission characteristics of an ultra-low NOxgas burner coupling with staging and swirling technology[J].Thermal Power Generation,2019,48(6):65-70.
- [9]方毅波,许优,陈力,等.新型超低NOx燃气燃烧器设计及数值模拟[J].电站系统工程,2019,35(4):8-10.FANG Yibo,XU You,CHEN Li,et al.Design andnumerical simulation of a new ultra-low NOxgas burner[J].Power System Engineering,2019,35(4):8-10.
- [10]王子叶.天然气轴向分级预混燃烧特性研究[D].北京:中国科学院大学(中国科学院工程热物理研究所),2019.WANG Ziye.Emissions characteristics of axial fuel staged combustor for gas turbine applications[D].Beijing:University of Chinese Academy of Sciences (Institute of Engineering Thermophysics,Chinese Academy of Sciences),2019.
- [11]AHRENS D,KOLB M,HIR SCH C,et al.Influence of preflame and postflame mixing on NOxformation in a reacting premixed jet in hot cross flow[J].Journal of Engineering for Gas Turbines and Power,2016,138(8):720-729.
- [12]惠鑫.合成气稀释扩散火焰的实验和数值研究[D].北京:中国科学研究生院,2007.HUI Xin.Experimental and numerical studieson diluted syngas diffusion flame[D].Beijing:Chinese Academy of Sciences,2007.
- [13]陈阳,罗开红.轴对称射流火焰的数值模拟及稳定性分析[J].工程热物理学报,2013,34(10):1973-1977.CHEN Yang,LUO Kaihong.Directnumerical simulation and stability analysis of an axisymmetric jet flame[J].Journal of Engineering Thermophysics,2013,34(10):1973-1977.
- [14]沈燕,陶常法,宗若雯,等.矩形喷口射流火火焰轴向温度研究[J].火灾科学,2017,26(2):87-92.SHEN Yan,TAO Changfa,ZONG Ruowen,et al.Axial temperature distribution of vertical jet flames from rectangular nozzles[J].Fire Safety Science,2017,26(2):87-92.
- [15]田超.低氮燃烧器的优化设计[D].徐州:中国矿业大学,2019.TIAN Chao.Optimal design of low nitrogen burner[D].Xuzhou:China University of Mining and Technology,2019.
- [16]王素娟.垂直分级水平浓淡煤粉燃烧器降低NOx排放的数值模拟[D].哈尔滨:哈尔滨工业大学,2007.WANG Sujuan.Numerical simulation of redusing NOxemission in vertical staged horizontal bias combustion burner[D].Harbin:Harbin Institute of Technology,2007.
- [17]郑建祥,耿如意,张驰,等.非预混甲烷湍流扩散火焰中碳烟生成的模拟研究[J].东北电力大学学报,2019,39 (6):37-43.ZHENG Jianxiang,GENG Ruyi,ZHANG Chi,et al.Simulation study on the formation of soot in non-premixed methane turbulent diffusion flame[J].Journal of Northeast Electric Power University,2019,39(6):37-43.
- [18]宋在乐.天然气扩散燃烧炭黑生成及与火焰辐射和NOx排放相互作用研究[D].上海:上海交通大学,2007.SONG Zaile.The interactional study of soot formation with flame radiation and NOxemission in natural gas diffusion combustion[D].Shanghai:Shanghai Jiaotong University,2007.
- 微火焰低氮燃烧器
- 数值模拟
- 天然气
- 过量空气系数
- NO_x
micro flame low nitrogen burners - numerical simulation
- methane
- excess air coefficient
- NO_x
- 宋佳霖
- 程星星
- 孙荣峰
- 王志强
- 耿文广
- 张兴宇
- 赵改菊
- 员冬玲
- 王鲁元
SONG Jialin - CHENG Xingxing
- SUN Rongfeng
- WANG Zhiqiang
- GENG Wenguang
- ZHANG Xingyu
- ZHAO Gaiju
- YUAN Dongling
- WANG Luyuan
- 宋佳霖
- 程星星
- 孙荣峰
- 王志强
- 耿文广
- 张兴宇
- 赵改菊
- 员冬玲
- 王鲁元
SONG Jialin - CHENG Xingxing
- SUN Rongfeng
- WANG Zhiqiang
- GENG Wenguang
- ZHANG Xingyu
- ZHAO Gaiju
- YUAN Dongling
- WANG Luyuan