摘要
研究利用Flic和Fluent耦合计算,进而准确有效预测某900 t/d焚烧炉内的温度分布。改造前的数值模拟结果表明,炉膛壁面严重的高温腐蚀的原因主要是二次风口位置不合理和炉排速度不合适。利用计算流体力学(CFD)进行一系列的数值模拟实验,研究炉排速度和堆料厚度、折焰角是否布置、二次风管的排列方式、前后拱二次风和烟道二次风风口位置对于炉膛燃烧过程的影响。结果表明:合适的炉排速度和加装折焰角可以改进炉膛底部的燃烧情况;二次风管采用切圆布置方式可以强化对于高温烟气的约束作用,减少壁面高温腐蚀;前后拱二次风可以加强炉拱区的扰动减少积灰;烟道二次风风口优化调整后,可以加强气流扰动,提高燃料的燃尽率。
This study uses Flic and Fluent coupling calculations in order to accurately and effectively predict the temperature distribution in a 900 t/d incinerator.The numerical simulation results before the transformation show that the severe high temperature corrosion of the furnace wall is mainly due to the improper position of the secondary air outlet and the inappropriate speed of the grate.A series of numerical simulation experiments are completed using computational fluid dynamics(CFD). The effects of grate speed and stock thickness, whether the flame angle is arranged, the arrangement of the secondary air duct, the secondary wind of the front and rear arches and the position of the secondary air outlet of the flue for the combustion process of the furnace are researched. The results indicate that the appropriate grate speed and the addition of the flame angle could improve the combustion of the bottom of the furnace.The secondary air duct adopts the tangential arrangement to strengthen the restraining effect on the high temperature flue gas and reduce the high temperature corrosion of the wall surface.The secondary winds of the front and rear arches can enhance the disturbance of the furnace arch area to reduce the ash accumulation; after the optimization of the secondary air vents of the flue, the airflow disturbance can be enhanced and the fuel burn-up rate can be improved.
引文
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