采用非预混稳态小火焰模型（Steady Flamelet Model，SFM）耦合110步甲烷燃烧简化机理和Realizable k-ε模型对反扩散-旋流低氮燃烧器进行模拟，对比分析了不同旋流角度（30°，45°和60°）及过量空气系数（1.05，110，115和1.20）下燃烧时燃烧室内各截面轴向速度分布、中心截面温度及NOx质量浓度分布。详细研究了燃烧室内天然气与空气的燃烧特性及NOx的排放规律。模拟结果表明：随着旋流叶片角度逐渐增大，燃烧室内回流作用逐渐增强，导致火焰长度变短、燃烧室内最高温度及出口NO质量浓度逐渐降低；在旋流叶片角度为60°时，出口NO质量浓度仅为114 mg/m3；随着过量空气系数逐渐增大，火焰末端温度逐渐提高，导致燃烧室出口NO排放量逐渐增大；在过量空气系数为1.2时，出口NO质量浓度达到294 mg/m3，相比于过量空气系数为1.05时，其NO排放量增加153%。

The nonpremixed steadystate small flamelet model (SFM) coupled with the 110step methane combustion simplification mechanism and the Realizable k-ε model were used to simulate the inversediffusionswirl lownitrogen burner. The axial velocity distribution, central section temperature and NOx mass concentration distribution on each section in the combustion chamber were compared and analyzed under different swirl angles (30°, 45° and 60°) and excess air coefficients (1.05, 1.10, 1.15 and 1.20). The influence law on the combustion characteristics of natural gas and air in the combustion chamber and NOx emission was studied in detail. The simulation results show that with the increase of swirl blade angle, the recirculation effect in the combustion chamber is gradually enhanced, resulting in shorter flame length, lower maximum temperature in the combustion chamber and lower outlet NO mass concentration. When the swirl blade angle is 60°, the outlet NO mass concentration is only 114 mg/m3; with the increase of excess air coefficient, the flame end temperature gradually increases, resulting in the increase of NO emission at the outlet of combustion chamber; when the excess air coefficient is 1.2, the outlet NO mass concentration reaches 294 mg/m3, compared with the excess air coefficient of 1.05, the NO emission is increased by 153 %.

TK16

国家自然科学基金（51906113）;江苏省高等学校基础科学（自然科学）面上项目（21KJB470006）