预混燃料径向分布对于燃烧性能的影响研究

Research on Influence of Premix Fuel Radial Distribution on Combustion Performance

为了有效降低氮氧化物排放,重型燃气轮机的燃烧器大都采用预混燃烧模式。预混燃料通过叶片燃料孔喷射出来,与空气混合后再进入燃烧室内燃烧。通过CFD数值模拟,分析燃料孔的不同径向布置对燃烧性能的影响,重点关注当量比分布、温度分布以及氮氧化物排放。结果表明,压力面燃料孔喷射出来的燃料预混效果比吸力面好,同时沿着吸力面从外径到内径依次减少孔数,预混燃料的混合效果依次增强,燃烧高温区缩小,氮氧化物排放减少。研究成果可用于燃烧器升级优化指导。

To reduce NOx emission,premix combustion model is mainly applied in burner design of gas turbine.Premix fuel is injected through fuel holes on blade and mixed with air,then is burned in the combustion chamber.Using CFD simulation,the influence of different radial distribution of fuel holes on combustion performance was analyzed,and attention was focused on equivalent ratio,temperature distribution and NOx emission.The result is demonstrated that the mixing effect of fuel holes on pressure side is better than that on suction side.Meanwhile,with reduction of holes on suction side at radial direction from outer to inner,the mixing effect is getting better,and the high temperature zone is reduced,resulting in NOx emission reduction.The research result can provide guideline for burner optimization design.