合成气稀释旋流扩散火焰稳定性研究

通过激光诱导荧光(PLIF)和照相等方法研究了合成气稀释旋流扩散燃烧特性。研究了空气、燃料旋流强度及它们相互配合对火焰稳定性的影响,发现燃料空气反向旋流情况中在扩张段出口上方具有较高的OH浓度,说明这种流动组织方式加强了初始阶段的混合,强化了化学反应,从而有利于燃烧的稳定;在所实验的范围内,强化空气旋流和燃料旋流都起到稳定燃烧的作用;在燃料和空气出口附加扩张段能起到稳定火焰的作用,在一定范围内,扩张段张角对火焰形态影响较大,扩张段张角小,火焰细长,扩张段张角大,火焰粗壮。

Study on the stability of the syngas diluted swirling diffuse flame

Swirling diffuse combustion characteristics of the syngas diluted was studied by PLIF and CCD image in this paper.The influence of air,fuel swirl intensity and their cooperativeness on the stability of syngas flame was studied.The experimental results show that the counter-flow flame can cause higher OH concentration at the exit boundary of the cone cover than the co-flow.This means that the counter-flow can strengthen the blend of the gases at the beginning stage,and intensify the chemical reaction.Therefore it is advantageous to combustion stability.It was discovered that either intensification of air swirl or intensification of fuel swirl can stabilize the combustion.Moreover,the additional conical expansion at the air and fuel exit can make the combustion more stable.The angle of conical expansion can exert important effects on the flame shape.The smaller the angle of divergence of the conical expansion outlet,the thinner and longer the flame;the larger the angle of divergence of the conical expansion outlet,the wider and the stronger the flame.