四角切向燃烧煤粉锅炉炉内气流组织与数值模拟

四角切向燃烧是我国电站煤粉锅炉广泛采用的燃烧方式。在实际运行中,由于气流在炉膛出口处有残余旋转,造成水平烟道两侧烟气的温度场和速度场分布不均,容易发生气流偏斜,导致火焰贴墙,引起结渣及燃烧不稳定。为了清楚地展示炉内气流分布情况,对四角切向燃烧煤粉锅炉炉内可能出现的几种气流组织工况分别进行了数值模拟,并分析了炉内气流的分布特性,得到了引起气流偏斜、火焰贴墙、结渣及燃烧不稳定的主要因素,为四角切向燃烧的煤粉锅炉内部的气流组织研究及其燃烧调整提供了重要的参考依据。

Air Distribution and Numerical Simulation on Tangentially Fired Pulverized Coal Boiler

Tangentially firing is a widely used combustion mode in our pulverized coal boilers. In real operation, since flow residual swirling in the outlet of the furnace causes uneven distribution in temperature filed and velocity field in horizontal flues passes, it is inclined to generate skewness, let the flame onto the wall, cause slag and unstable burning. The numeric simulations are made by possible flow distribution condition on tangentially fired pulverized coal boiler to show clearly the flow distribution in the furnace. And the distribution characteristics of flow are analyzed to reach the factors of flow skewness, flame onto wall, slag and unstable burning. Thus references are provided for the study of internal flow distribution and combustion commissioning against tangentially fired pulverized coal boiler.