对一台1,000,MW 超超临界锅炉中燃尽风(OFA)对 NOx 生成的影响进行了数值模拟，分析了燃尽风配风比例以及燃尽风的 SOFA 喷口风门位置对出口 NOx 的影响。结果表明：随着燃尽风配风比例的提高，由于主燃区过量空气系数减小导致还原性增强以及燃烬风补入空气对整体烟气的温度稀释和 NOx 体积分数稀释的增强，使得出口NOx 体积分数降低。而上移 SOFA 喷口风门位置，由于拉长了还原区的长度导致出口 NOx 降低。%The influence of OFA(over-fired air)on NOx formation in a 1,000,MW ultra-supercritical boiler was simu-lated.The effects of the percentage of OFA and the postion of SOFA nozzles were analyzed.The analysis results indi-cated that with the increase in the percentage of OFA,the reducing atmosphere was strengthened by the reduced ex-cess air ratio in the primary combustion zone,and the temperature and concentration were diluted by OFA air,thus reducing the outlet NOx concentration. Shifting the SOFA nozzles increased the length of reduction zone,hence de-creasing the NOx concentration.
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