富氢燃料贫预混旋流燃烧热声振荡特性的实验研究

摘要

贫预混燃烧是实现富氢燃料燃气轮机低NOx 燃烧的有效途径之一，但是贫预混燃烧极易产生热声振荡，热声振荡会干扰燃烧过程，对燃烧室的结构造成破坏。本文通过实验分析了当量比、燃料组分以及空气质量流量对热声振荡特性的影响。结果表明：在动态压力功率谱上有两个明显的峰值，其频率均随当量比的增加而增加，同时当量比也会影响振荡强度；氢含量越高，越容易发生热声振荡，提高氢含量会影响热声振荡的特性，当氢含量达到一定值之后再提高氢含量对热声振荡特性的影响变得不明显；空气质量流量越大，振荡强度增大，稳定燃烧的范围变小。%Lean-premixed combustion appears to be the most effective dry low NOx emission technology for gas turbines fueled with hy-drogen-enriched gas, butit easily lead to thermoacoustic oscillation.It may cause high levels of noise andpotential constructive combus-tion failure of the combustion system.In the presentwork, the influences of equivalence ratio, fuel composition and the air mass flow rate on the characteristics of thermoacoustic oscillation are investigated by experimental methods.Experimental results show that there are two obvious peaks in the dynamic pressure power spectrum.The frequency of the two peaks are f1 and f2 respectively.Both f1 and f2 increase with the increase of equivalence ratio.Equivalence ratio also have influences on the intensity of oscillation.The higher of the hydrogen content, more easily thermoacoustic oscillation.With the increasing of hydrogen content, the characteristic of ther-moacoustic will become different, but when the hydrogen content reaches a certain value, further increasing the hydrogen content, some characteristic of thermoacoustic will almost not changed.In addition,with the increasing of air mass flow rate, the intensity of oscilla-tion would be stronger, and the range of keeping stable combustion will become smaller.