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.
作者
杨怀远
张彭岗
潘振华
YANG Huai-yuan;ZHANG Peng-gang;PAN Zhen-hua(Energy and Power Engineering College, Jiangsu University, Zhenjiang 212013, China)
出处
《科学技术与工程》
北大核心
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。
关键词
环形通道
火焰加速
舌形火焰
不稳定性
爆轰起爆
curved channel
flame acceleration
tongue-like flame
instability
onset of detonation
