【摘要】 以小型液态排渣煤粉燃烧器为研究对象,利用FLUENT软件对该燃烧器燃烧状况进行数值模拟,获得燃烧器内的流场、温度场、氧浓度分布场和氮氧化物质量浓度分布场等,研究了预热风温和三次风率对氮氧化物生成的影响。模拟结果表明,由于钝体的存在,燃烧器内形成了较大的回流区;空气旋流进入后与煤粉混合较好,燃烧器内温度场与氧浓度分布均较对称,NO浓度分布也较合理;预热风温对NO生成量影响不大,三次风率对燃烧器的燃烧影响较大。研究结果可为进一步提高燃烧器性能提供依据。更多还原

【Abstract】 A small liquid-slag pulverized coal burner was taken as the research object. The combustion state of the burner was numerically simulated by FLUENT.The flow field, temperature field, oxygen concentration distribution field and nitrogen oxide mass concentration distribution field in the burner were obtained. The effect of preheated air and tertiary air rate on nitrogen oxide products was studied.Simulation results show that a large reflux zone is formed as a result of the existence of bluff bodyin the burner.The air swirl enters into the burner and mixes well with pulverized coal. The temperature field and oxygen concentration distribution in the burner are symmetrical, and the NO concentration distribution is reasonable. Effect of preheating air temperature on NO production is little, while tertiary air rate has great influence on combustion of burner.Simulation results provide a basis for further improvement of burner.更多还原