预热室结构对多段式自预热燃烧器内燃烧及NOx排放特性的影响

提出了一种多段式自预热燃烧器及其4种典型的预热室结构，通过计算流体力学（CFD）方法研究了燃烧室内流场、烟气卷吸率、温度场、燃气燃尽率以及NOx体积分数，并与传统燃烧器的情况进行了对比．结果表明：与传统燃烧器相比，多段式自预热燃烧器改变了燃烧室内流场，对低热值燃料适应性强，其预热室结构同时影响烟气卷吸率和预热效果，并最终影响燃尽率与NOx体积分数；此外，燃烧器负荷对燃尽率影响甚微，但对NOx体积分数影响较大．

Effects of the Structure of Preheating Chamber on Combustion and NOx Emission of a Multi-stage Self-preheating Burner

An introduction is being presented to the structure of a multi-stage self-preheating burner and its four typical preheating chambers. Through CFD simulation, the flow field, flue gas recirculation rate, temperature field, fuel gas burn-out rate and volumetric fraction of NOx in the combustion chamber have been calculated and analyzed in comparison with that of traditional burners. Results show that compared with traditional burners, the proposed burner has a different flow field and a higher adaptability to fuels of low heating values; the structure of its preheating chamber influences both the flue gas recirculation rate and the preheating effectiveness, and therefore accordingly influences the burn-out rate and NOx emission. Furthermore, the load of the burner affects less on the burn-out rate, but more on NOx emission.