摘要
利用高速纹影法研究初始压力和当量比对氢一空层流预混火焰传播特性的影响规律.分析了火焰传播过程中火焰表面拉伸作用的变化趋势,探讨了火焰固有不稳定性的决定因素,研究了表面拉伸作用和固有不稳定性对传播速度的影响,求取了氢-空火焰传播过程中的加速指数.结果指明,表面拉伸作用随火焰的传播而衰减,火焰不稳定倾向相应增强;当火焰表面发展为完全胞状态时,火焰传播速度突然增加,并以自加速的现象持续.氢-空预混火焰的加速指数随燃空当量比减小而增大,随初始压力增大而增大.
High-speed schlieren technology is employed to study the effects of initial pressure and equivalence ratio on the propagation characteristics of hydrogen-air flames. The flame stretch effects are analyzed, the dominant roles on intrinsic flame instability are discussed, the effects on propagation speed are studied, and the values of acceleration exponent are determined. The results indicate that, the flame stretch effects decline as flame propagates, and flame tends to unstable. Once the flame front becomes totally cellular, the propagation speed is sharply increased, and the flame will propagate within self-acceleration mode. The acceleration exponent of hydrogen-air flame increases with the decrease of equivalence ratio and/or the increase of initial pressure.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2013年第12期2413-2417,共5页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.50976014
No.51276019)
国家高技术研究发展计划(863计划)资助项目(No.2006AA11A1B6)
关键词
氢气
火焰传播特性
火焰形态
火焰传播速度
火焰自加速
hydrogen
flame propagation characteristics
flame morphology
propagation speed
self-acceleration
