烟气内循环下甲烷燃烧过程的模拟研究  

Simulation Study on Methane Combustion Process under Internal Circulation

作　　者：何俊杰 朱彤[1] 潘登[1] HE Junjie;ZHU Tong;PAN Deng(Department of Mechanical Engineering,Tongji University,Shanghai 201804,China)

机构地区：[1]同济大学机械与能源工程学院,上海201804

出　　处：《工业锅炉》2023年第6期7-13,共7页Industrial Boilers

摘　　要：氮氧化物(NO_(x))是燃烧产生的一种有害气体。为了满足低氮排放标准,烟气循环是减少NO_(x)生成的有效方式。以一台带有烟气内循环的1.4 MW油气两用燃烧器为研究对象,设计了燃烧器和燃烧室的几何结构;采用燃烧过程数值模拟方法,分析了燃烧器旋流器叶片安装位置、叶片数目、形状等参数对燃气燃烧过程NO_(x)生成特性的影响。通过数值模拟,得到了燃气燃烧过程的流场、温度场、组分场以及氮氧化物分布的详细信息,揭示了燃烧室内流动、燃烧和传热过程的特点及其产生的原因。通过模拟分析发现,带有烟气内循环的燃烧器旋流器含6个倾角为37°的扇形叶片,叶片距离空气渐缩口60 mm为较佳结构,额定功率下NO_(2)排放量为29.9 mg/m^(3),相比无旋流器工况NO_(2)排放量降低了76.7%。Nitrogen oxides(NO_(x))is a harmful gas produced by combustion.Flue gas recirculation is an effective measure to reduce NO_(x)generation to meet low-nitrogen emission standards.A 1.4 MW dual-fuel burner with internal flue gas recirculation has been focused on,and the geometric structure of the burner and combustion chamber have been de-signed.The numerical simulation has been used to analyze the effects of burner swirler installation position,blade number,and shape on NO_(x)generation characteristics during methane combustion.Through numerical simulation,detailed informa-tion on the flow field,temperature field,composition field,and NO_(x)distribution in gas combustion process have been ob-tained,the characteristics and causes of flow,combustion,and heat transfer processes in the combustion chamber have been revealed.Simulation analysis shows that the burner swirler with six sector blades inclined at 37°and the blade distance of 60 mm from the air gradually shrinking mouth is the optimal structure,with a NO_(2)emission rate of 29.9 mg/m^(3)at rated power,which reduces NO_(2)emissions by 76.7%compared to the no-swirler condition.

关 键 词：甲烷燃烧 烟气内循环 卷吸 NO_(2)排放 

分 类 号：TK223.23[动力工程及工程热物理—动力机械及工程]