中文摘要：

柔和燃烧具备燃烧稳定、烟气出口温度均匀、NO和CO排放低的特点,有望成为新一代燃气轮机燃烧技术。因此,开展柔和燃烧技术应用于燃气轮机燃烧室的探索研究非常必要。烟气温度、氧浓度及其与新鲜空气的掺混对柔和燃烧的发生及燃烧性能有重要影响。为此,基于轴向分级概念建立燃烧器,通过精确控制烟气回流比例和当量比使得烟气的流量、温度、氧浓度连续可调,设计合适的燃烧器结构型式使得烟气在掺混区和燃料、空气以交叉射流方式掺混。通过数值模拟结合实验的方法,从流动、热力学角度研究分析了回流比例、当量比对OH^﹡分布、火焰稳定性、NO/CO排放等燃烧性能的影响规律和机制。实验以甲烷为燃料,在回流比例r 0.5、当量比0.6工况下获得最佳的污染物排放性能：NO为6 mg/m^3,CO为5 mg/m^3。研究结果将为柔和燃烧在燃气轮机燃烧室上的应用提供理论依据和基础数据。

英文摘要：

Moderate ＆ intense low oxygen dilution （MILD） combustion characterized by low NO and CO emissions, stable combustion and improved pattern factor was expected to be a sound option for future gas turbine combustion technology. It was necessary to study MILD combustion based on gas turbine application. Considering the role of gas temperature as well as oxygen mole fraction and mixing performance between gas and fresh air on MILD combustion realization and combustion performance. Investigation The shows an axially-staged combustor, in which gas recirculation ratio and equivalence ratio can be accurately adjusted to control flow rate, temperature and oxygen mole fraction of exhaust gas. Gas emitting from the pilot burner mixed with secondary fresh fuel and air based on cross-flow jet mixing. Effects of gas recirculation ratio and equivalence ratio on OH＊ chemiluminescence distribution, flame stability as well as NO/CO emissions were studied experimentally and numerically. The burner is methane fueled and ultra-low NO （6 mg/m^3, r=- 0.5, 00=0.6） and CO （5 mg/m^3, r=0.5, 00=0.6） emissions are achieved for present combustor. Results obtained in this study are essential to MILD combustion application in gas turbine combustors.