叶片数对煤粉燃烧机燃烧性能的影响分析

Impact Analysis of Blade Number on Combustion Performance of Pulverized Coal Burner

以沥青搅拌站设备煤粉燃烧机为研究对象,分析其旋流器叶片数对煤粉燃烧机燃烧性能的影响规律。基于旋流风产生原理及煤粉燃烧机工作原理,构建旋流式煤粉燃烧机内部流场模型,运用CFD软件对煤粉燃烧机内部场燃烧过程进行数值模拟。以旋流器叶片数为影响因素,分析其对煤粉燃烧机内部污染物质量分数分布、颗粒运动轨迹的影响规律。结果表明:当旋流器叶片数在[8,10]时,整个计算域上各生成物均无明显变化;当旋流器叶片数在(10,12]时,燃烧器内部漩涡扩散到两端导致高温烟气的回流与卷吸效果降低,使得燃烧器内部的燃烧变缓慢,从而降低了燃烧效率,并且NO排放量增加。

Taking the pulverized coal burner of asphalt mixing plant as the research object,the paper analyzes the impact of the number of swirler blades on the combustion performance of the pulverized coal burner.Based on the generation principle of swirling wind and the working principle of the pulverized coal burner,the internal flow field model of the swirling pulverized coal burner was constructed,and the combustion process was simulated by CFD software.As a factor,the influence of the number of blades on the distribution of pollutant mass fraction and particle movement trajectory in the pulverized coal burner was analyzed.The results show that,with 8 to 10 blades,there is no significant change in the products in the computational domain;with 10 to 12 blades,the vortex inside the burner diffuses to both ends,which reduces the back-flow and entrainment of the high-temperature flue gas,slows down the combustion,reduces the combustion efficiency,and then increases the NO emission.