火焰在环形通道内形态演变的实验研究  

Experimental Investigation on Flame Behavior in Curved Channel

作　　者：杨怀远 张彭岗[1] 潘振华[1] YANG Huai-yuan;ZHANG Peng-gang;PAN Zhen-hua(Energy and Power Engineering College, Jiangsu University, Zhenjiang 212013, China)

机构地区：[1]江苏大学能源与动力工程学院,镇江212013

出　　处：《科学技术与工程》2021年第15期6291-6296,共6页Science Technology and Engineering

基　　金：国家自然科学基金(51876084);天津大学内燃机国家重点实验室基金。

摘　　要：采用实验方法研究环形通道内体积比为1∶3的乙烯/氧气混合气体以及体积比1∶2.5的乙炔/氧气/氩气混合气体的火焰形态演变过程。实验方面采用高速摄影观察环形通道内的火焰传播。火焰经历了四个主要阶段:球形火焰、手指型火焰、舌形火焰和爆轰,其中舌形火焰在整个爆燃到爆轰转变(deflagration to detonation transition,DDT)过程中占据了最长的时间,并且在爆轰起爆中占据重要作用。另外,舌形火焰与边界层的作用使得火焰表面积和火焰速度有所增加。也讨论了初始压力对DDT起爆距离的影响,对于同种气体,初始压力的增大有助于缩短DDT起爆距离。此外,在爆轰敏感性相同的前提下,不规则系统中的DDT起爆距离要短于规则系统中的DDT起爆距离。The evolution of flame behavior for stoichiometric ethylene/oxygen and acetylene/oxygen/argon mixtures in a curved channel was experimentally investigated.Flame propagation through the curved channel was observed by a high-speed changed-coupled device(CCD)camera.Four main phases were divided as follows:spherical flame,finger flame,tongue-like flame,and detonation.The evolution of the tongue-like flame occupies most of time in the whole DDT process,which plays critical role in the onset of detonation.The interaction between tongue-like flame and boundary layer enhances the flame surface as well as the flame velocity.The influence of initial pressure on DDT run-up distance was discussed,it is confirmed that the increasing initial pressure enhances the DDT run-up distance,for the same type of system.In addition,the DDT run-up distance in irregular system is shorter than that in regular system with the same detonation sensitivity.

关 键 词：环形通道 火焰加速 舌形火焰 不稳定性 爆轰起爆 

分 类 号：TJ011.1[兵器科学与技术—兵器发射理论与技术]