卫燃带布置高度对燃煤锅炉烟温的影响

Effect of the Refractory Belt's Height on the Flue Gas Temperature of Coal-fired Boilers

通过数值模拟与理论推导相结合的方式以1台300 MW锅炉为对象,研究了卫燃带布置高度对特征截面温度、炉内温度场和火焰中心高度的影响,并对热力计算方法进行了修正。研究结果表明,卫燃带布置在燃烧器区域时,其布置高度对炉膛出口烟温造成了6℃左右的影响,炉膛出口烟温随着卫燃带布置高度的增加而增大。修正的热力计算方法中,M随着卫燃带高度发生变化;随着卫燃带高度增加,M减小。卫燃带布置高度变化引起火焰中心高度发生变化,由此引起的M变化量在0.000 1数量级;由炉膛温度场和几何结构变化等因素引起的M变化量在0.001数量级。以上研究结论基于数值模拟和理论推导,其准确性有待现场试验的进一步检验。

In this paper,both numerical simulation and theoretical derivation are adopted in a300 MW boiler to study effects of the refractory belt＇s height on temperature of the characteristic cross-sectional areas,the furnace temperature field and height of the flame centre.Results show that the refractory belt＇s height affects the flue gas temperature at furnace exit by about 6 oC.The flue gas temperature at the furnace exit will increase with the refractory belt＇s height.Based on these results,a revised thermodynamic calculation method is proposed.In this method,the Mis decreased as the refractory belt＇s height is increased.The change of Mcaused by variation of the flame centre is in the magnitude of 0.0001.While the change of M caused by variations of the furnace temperature field and the furnace geometry is in the magnitude of 0.001.These conclusions are obtained by numerical simulation and theoretical analysis,and the accuracy needs to be further verified.