甲醇裂解气对甲烷-空气预混层流燃烧特性的影响  

Effects of Dissociated Methanol Gas Addition on Laminar Burning Characteristics in Methane-Air Premixed Flames

作　　者：贾若愚 秦静[1,2] 裴毅强[1] 胡铁刚 刘斌 王振平 

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072 [2]天津大学内燃机研究所,天津300072 [3]长安动力研究院,重庆400023

出　　处：《内燃机学报》2018年第1期51-59,共9页Transactions of Csice

基　　金：国家科技支撑计划资助项目(2014BAG10B01)

摘　　要：采用定容燃烧弹-纹影系统,将H_2与CO按体积比为2∶1的混合气来模拟真实甲醇裂解气,进行了初始温度为343,K、初始压力为0.3,MPa下的甲烷-甲醇裂解气-空气预混燃烧试验,研究了不同当量比(0.6~1.8)和不同添加比例(20%,~80%,)的甲醇裂解气(其中V(H_2)∶V(CO)=2∶1)对甲烷-空气层流火焰燃烧速度、马克斯坦长度、火焰胞状结构及其影响参数等层流燃烧特性的影响,并在相同条件下单独添加CO,探究CO在甲醇裂解气中的作用.结果表明:甲醇裂解气能提高混合气层流火焰燃烧速度,在整个当量比范围尤其是稀燃时加强火焰不稳定性,促进胞状结构的产生.CO也能提高燃烧速度,但提升幅度比甲醇裂解气小,而且只有在大比例添加且当量比为1.2附近时才对火焰胞状不稳定性产生明显促进作用,即甲醇裂解气中对甲烷层流燃烧速度和火焰稳定性起主要影响的成分为H_2.Experiments were conducted in a constant-volume combustion chamber by using a schlieren system to study laminar burning velocities and flame cellular instabilities of a methane-air premixed flame at mixing equivalence ratios from 0.6 to 1.8 and dissociated methanol fractions from 20% to 80%. In the mixture, H2 and CO with a volume ratio of 2 ： 1 （V（H2） ： V（CO） = 2 ： 1 by volume） was used to simulate the real dissociated methanol. The experiment was carried out at the temperature of 343 K and the pressures of 0.3 MPa. In addition, the effect of CO on the laminar flame was also studied by only adding CO in the combustion chamber at the same conditions. The results show that the dissociated methanol enrichment can significantly increase unstretched laminar burning velocities and improve flame cellular instabilities （especially for lean conditions）. Adding CO can also promote the burning velocities, but the no- ticeable improvement of cellular instabilities can only be observed at the conditions of large CO fraction and an equiva- lence ratio of about 1.2. This means that H2 plays a more important role than CO for laminar burning velocities and flame cellular instabilities in dissociated methanol gas.

关 键 词：甲醇裂解气 甲烷 一氧化碳 层流燃烧速度 胞状稳定性 

分 类 号：TK411[动力工程及工程热物理—动力机械及工程]