烟气自循环式低氧燃烧器燃烧过程的数值模拟

Numerical simulation of a low oxygen burner with self-circulation of flue gas

在分析了工业中几种低氧燃烧方式的基础上,将收缩-扩张结构用于燃烧器空气通道,开发出了烟气自循环式低氧燃烧器,同时借助FLUENT软件对燃烧器进行了大量数值模拟研究.结果表明:喉部的负压是烟气卷吸的驱动力,烟气卷吸量随喉部面积的缩小而急剧增多;随着烟气卷吸量的增多,炉膛中氧含量越来越低,火焰高温区向燃烧器偏移,火焰逐渐变短.最后,将烟气自循环式低氧燃烧器用于熔化保温炉进行了实践,取得了预期的效果.

Based on the analysis of some kinds of low oxygen combustion, a low oxygen burner with self-circulation of flue gas was developed with contracted/dilated air channels. The Fluent software was used for numerical simulation of the burner. The results show that the negative pressure at the throat is the driving force of fume entrainment, and the volume of fume entrainment increases dramatically with the decrease of throat area. Because of the increase of fume entrainment, the oxygen concentration in the furnace decreases, the high-temperature zone of the flame moves to the burner, and the length of the flame also becomes short. At last, the low oxygen burner with self-circulation of flue gas was applied to a melting holding furnace, and the anticipated effect was achieved.