喷管结构对甲烷微混燃烧特性的影响研究  

Effect of tube structure on methane micro-mixing combustion characteristics

作　　者：蒿宇 雷福林[1,2] 张哲巅 HAO Yu;LEI Fulin;ZHANG Zhedian(Key Laboratory of Advanced Energy and Power,Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing 100190,China;School of Engineering Sciences,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院先进能源动力重点实验室(工程热物理研究所),北京100190 [2]中国科学院大学工程科学学院,北京100049

出　　处：《热力发电》2023年第1期26-35,共10页Thermal Power Generation

基　　金：国家科技重大专项(Y2019-I-0022-0021)。

摘　　要：微混燃烧是一种具有潜力的低污染燃烧技术,而作为基础单元的微管结构对燃烧特性有显著的影响。以单元微管模型燃烧器为对象,在空气预热加压和常温常压2组工况下,使用计算流体力学方法分析了不同微管直径、微管后段长度、火焰筒微管面积比时的甲烷微混燃烧特性。数值模拟结果表明:常温工况的火焰长度明显增长,并且增幅受到微管直径和面积比的影响较大;随着微管直径增大,火焰筒内流场和温度场基本相似,无量纲火焰长度变化不大,但是微管直径更小时2组工况的火焰长度变化更小,具有更好的适应性;随着微管后段长度增加,微管出口湍流强度大幅降低,火焰长度明显增加,2组工况下火焰长度的变化趋势较为一致;随着火焰筒与微管面积比增加,火焰长度有先缩短后增长的趋势,而面积比在4.0~9.0时火焰长度较短,燃烧性能较好。研究结果对燃气轮机燃烧室具有参考价值,对自由射流火焰也有一定的参考意义。Micro-mixing combustion is a kind of potential technology to reduce pollutant emissions, and the microtube structure as a basic unit has significant influence on combustion characteristics. Taking the single microtube model burner as the object, the computational fluid dynamics(CFD) method is employed to analyze methane micro-mixing combustion characteristics with different microtube diameters, rear-section lengths, and chamber-to-tube area ratios, under the air-preheated and pressurized condition and the atmospheric condition. The numerical simulation results show that, the flame length increases obviously under the atmospheric condition, and the increase rate is greatly affected by the microtube diameter and the area ratio. With the increase of microtube diameter, the flow and temperature fields in the flame chamber are similar, and the dimensionless flame length does not change significantly. However, when the microtube diameter is smaller, the change of flame length is smaller between two working conditions, and the flexibility is better. With the increase of microtube rear-section length, the turbulence intensity at the microtube outlet reduces greatly, and the flame length increases obviously, but the change trend of flame length is consistent under two working conditions. With the increase of chamber-to-tube area ratio,the flame length decreases at first and then increases. When the area ratio is 4.0~9.0, the flame length is relatively short, and the combustion performance is relatively good. The results have reference value for the gas turbine combustor, and also have certain reference significance for free jet flame.

关 键 词：模型燃烧器 喷管结构 微混燃烧 火焰长度 燃烧特性 

分 类 号：TK16[动力工程及工程热物理—热能工程]