氧体积分数对甲烷同轴射流扩散火焰碳烟形貌的影响  

Effects of Oxygen Concentration on Soot Morphology Evolution of Methane Coflow Jet Diffusion Flame

作　　者：曹文健 韩伟伟 卫言 任飞 楚化强 顾明言 Cao Wenjian;Han Weiwei;Wei Yan;Ren Fei;Chu Huaqiang;Gu Mingyan(School of Energy and Environment,Anhui University of Technology,Ma＇anshan 243002,China)

机构地区：[1]安徽工业大学能源与环境学院,马鞍山243002

出　　处：《燃烧科学与技术》2018年第4期361-368,共8页Journal of Combustion Science and Technology

基　　金：国家重点研发计划资助项目(2017YFB0601805);国家自然科学基金资助项目(51676002)

摘　　要：针对甲烷同轴射流火焰,利用直径12,μm的Si C纤维沉积采样,并结合场发射扫描电子显微镜观测和热电偶测温,研究了富氧(O2/N2)气氛对火焰中碳烟沉积物形态演变的影响.结果表明:火焰中碳烟沉积物形态强烈依赖于其在火焰径向、轴向的位置和氧体积分数的变化.随氧体积分数由21%,上升到31%,,同一火焰高度处,碳烟生成量迅速增加,碳烟初生位置提前,初生碳烟颗粒粒径为20~36,nm,火焰高度增加,火焰边缘尺寸较大的团簇状的碳烟沉积物逐渐演变为更为致密的絮状、海绵状和纤维状碳烟沉积物.To investigate the effect of oxygen-enriched（O2/N2）atmosphere on the morphological evolution of soot deposition in a methane coflow jet diffusion flame,a 12,μm Si C fiber deposition sampling method,combined with the observations by field emission scanning electron microscopy（FESEM） and thermocouple thermometry,was adopted.Results show that the morphology of soot deposits strongly depends on their radial and axial positions in the flame and oxygen volume fraction.With the increase of oxygen volume fraction from 21%, to 31%,,at the same flame height,the soot generation rate increases rapidly,the position of soot inception is advanced,and the primary soot particle size is approximately 20—36,nm. As the flame height increases,the large clusters of soot deposits gradually evolve into even denser flocculent,sponge-like,and fibrous soot deposits around the flame edges.

关 键 词：同轴射流 碳烟 沉积形态 SIC纤维 

分 类 号：TK16[动力工程及工程热物理—热能工程]