二乙醚-空气预混合气层流燃烧速率测定

Measurement of Laminar Burning Velocities of Diethyl Ether-Air Premixed Mixtures

在定容燃烧弹内利用高速纹影摄像法系统地研究了不同初始压力、不同初始温度和不同燃空当量比下二乙醚-空气预混合气的层流燃烧特性。利用球形发展火焰分析得到了不同初始压力、不同初始温度和不同燃空当量比下二乙醚-空气预混合气的无拉伸层流火焰燃烧速率、马克斯坦长度等层流燃烧参数。研究结果表明:无拉伸层流火焰燃烧速率随初始温度的增加而增加,随初始压力的增加而降低;马克斯坦长度随着初始温度的增加而减小,随初始压力的增加而减小,随当量比的增加而减小,表明火焰前锋面不稳定性随初始温度和初始压力的增加而增加,随混合气浓度的增加而增加。基于试验数据获得了二乙醚-空气预混合气无拉伸层流燃烧速率的关系式。

Measurement of laminar burning velocities of diethyl ether-air mixtures were conducted at different initial pressures, initial temperatures and equivalence ratios by using the spherically propagating flame and schlieren photography method. The results show that the unstretched laminar burning velocities are increased with the increase of initial temperature and the decrease of initial pressure. Markstein lengths are decreased with the increase of initial temperature, initial pressure and equivalence ratio, indicating an increasing in instability of flame front with the increase of initial temperature, initial pressure and equivalence ratio. Based on the experimental data, a formula of the unstretehed laminar burning velocity is correlated.