660 MW超超临界旋流对冲燃煤锅炉二次风配风方式对NOx分布影响的数值模拟

为了研究二次风配风方式对NOx生成的影响，针对某电厂660 MW超超临界旋流燃煤锅炉，利用Ansys软件数值模拟研究了二次风配风方式对NOx生成规律。数值模拟的结果与现场实际情况较吻合，验证了数值模拟结果的有效性，主要结论有：炉膛燃烧器区域是NOx的主要生成区；在第1层和第2层燃烧器之间区域NOx浓度较高，然后沿炉高方向NOx浓度逐渐降低；随着燃尽风量的增加，炉内高度方向各个截面的NOx平均浓度降低；随着燃尽风量增加，炉膛出口截面NOx浓度逐渐降低，但下降量逐渐减少。

Numerical Simulation of Second Air Distribution Influence on Concentration of NO_x Distribution for Swirl Opposed Wall Firing Pulverized Coal Boiler in 660 MW Ultra Supercritical Unit

In order to investigate the influence of second air distribution on NO x formation,this paper numerically simulated the NO x formation rule by using Ansys for the swirl pulverized coal boiler in a 660 MW ultra-supercritical power plant. The numerical results agree well with actual conditions,which verify the effectiveness of the numerical simulation results. The main results are summarized as follows： the burner in furnace is the mainly region of NO x formation; the concentration of NO x between the first layer and second layer of combustion zone is higher; the concentration of NO x decreases along the furnace height; with the increasing of burnout-air,the mean concentration of NO x at each cross-section zone decreases along the height of boiler,and the mean concentration of NO x at the burner outlet decreases,but the decreasing rate is more and more slow.