甲烷量对模拟煤层气层流燃烧速度的影响

摘要

利用定容燃烧弹和高速纹影摄像系统研究了常温常压下模拟煤层气中甲烷含量对其层流燃烧速度的影响,得到了在不同当量比下甲烷含量对模拟煤层气层流火焰传播速度和层流火焰燃烧速度的影响规律.结果表明,随着模拟煤层气中甲烷含量的降低,混合气的拉伸层流火焰传播速度、无拉伸层流火焰传播速度在不同的当量比下均减小；化学当量比附近,不同甲烷含量对应的无拉伸层流火焰传播速度之间的差值较大.无拉伸层流火焰燃烧速度随甲烷含量变化的规律与无拉伸层流火焰传播速度变化的规律类似.%Influence of methane concentration on laminar burning velocity of coal-bed gas under normal temperature and pressure is studied in constant volume combustion bomb with the help of high-speed camera digital schileren photography. Influence of methane variation on laminar propagation speed and laminar burning velocity of coal-bed gas under different equivalence ratios is obtained. The experimental results show that with the decrease of methane concentration, both stretched laminar propagation speed and unstretched laminar propagation speed of combustible mixture decrease under different equivalence ratios. The unstretched laminar propagation speed that corresponds to different methane concentrations varies greatly under stoichiometric conditions. The principle of methane variation to unstretched laminar burning velocity and propagation speed vary similarly with methane concentration.