氢气比例和点火能量对CH4-H2混合气体爆炸强度影响的实验研究

Experimental Study of the Hydrogen Proportion and Ignition Energy Effects on the CH4-H2 Mixture Explosion Intensity

在20 L标准球形爆炸罐内开展了当量比为1的甲烷-氢气-空气混合气体爆炸实验,通过改变点火能量和氢气体积分数,探讨点火能量和气体比例对其爆炸压力和爆炸强度的影响。研究发现:氢气比例越高,爆炸冲击波传播速度越快,点火能对冲击波传播速度的影响相对较小;点火能量的提高对峰值超压有增强作用,氢气比例低时,此增强作用较显著,氢气比例高时,此增强作用较弱;点火能量对爆炸强度指数KG的影响较小,而氢气比例对爆炸强度指数KG的影响十分明显,氢气比例低于50%时,氢气比例的增加对爆炸强度的增强作用较弱,氢气比例高于50%时,氢气的增加对爆炸强度的激励作用急剧增强。另外发现,相同当量比条件下,氢气的爆炸强度指数近似为甲烷爆炸强度指数的10倍。

CH4-H2 mixture explosion experiments were performed in a 20 L spherical explosion vessel with the equivalence ratio of 1.Gas proportion and ignition energy were varied to explore their effects on the explosion pressure and intensity.It is found that higher hydrogen proportion causes higher explosion shock wave propagation speed,while the ignition energy has little effects on the explosion shock wave propagation speed.Higher ignition energy can enhance the explosion overpressure,and this enhancement effect is remarkable when the hydrogen proportion is lower,and is not evident when the hydrogen proportion is higher.The effect of ignition energy on the explosion severity index KG is not evident,but the effect of hydrogen proportion on KG is remarkable.The positive effect of hydrogen addition on KG is very slight at low hydrogen proportion while it becomes much more pronounced at higher hydrogen contents.Furthermore,the explosion intensity of hydrogen is approximately tenfold of that of methane explosion with corresponding same equivalent ratio,and therefore,the presence of hydrogen will greatly enhance the explosion hazard of methane.