600MW“W”型火焰锅炉炉内燃烧过程的数值模拟

为了分析"W"型火焰锅炉爆管原因,对某电厂某台600MW"W"型火焰锅炉在100%,75%和50%负荷下以及不同煤质情况下的燃烧过程进行数值模拟计算,研究不同负荷及不同煤质时锅炉炉内速度场、温度场的分布。研究结果表明:100%负荷和50%负荷下速度场和温度场比较对称,75%负荷下则出现明显的偏斜;在100%负荷下,火焰冲刷下炉膛的前后墙两端较严重;在50%负荷下,炉膛火焰中心有所下移,冷灰斗处温度较高;在75%负荷下,后墙火焰冲刷前墙严重,上炉膛温度偏高以致过热器温度过高,这些区域都容易引起受热面结渣和爆管。

Numerical simulation on combustion process of 600 MW W-flame boiler

In order to understand reasons of pipe expansion for W-flame boiler,numerical simulation on combustion process from 100%,75%,50% loads and different coals were conducted in the certain 600 MW W-flame boiler of certain power Plant.The results indicate that the temperature field and the flow field are symmetrical on the load of 100% and 50%,but the load of 75% remarkably causes skew,the flame badly sweeps over the front and back wall of ends in lower hearth in the load of 100%,the flame center is decreased and the temperature of cold ash hopper is higher in the load of 50%,the flame of back wall sweeps over front wall and temperature of upper hearth is too high and makes superheater over-temperature on the load 75%,all of these zones can lead to slagging and pipe expansion of water screen.