600 MW超超临界燃煤锅炉燃烧特性数值模拟研究

Numerical Simulation Study on Combustion Characteristics of 600 MW Ultra-supercritical Pulverized Coal Boiler

为了能提升锅炉燃烧特性,改进锅炉结焦难题,文中选取600 MW超超临界、直流、对冲燃烧锅炉作为研究对象,选用CFD数值模拟方法对该锅炉炉膛内二相流动性、燃烧现象、传热传质特性展开了仿真模拟根据数据分析燃烧器位置和燃尽风位置温度云图、炉膛温度场云图以及沿炉膛高度方向O 2浓度、CO浓度、CO 2云图分布情况,阐述了炉内的空气动力场、温度梯度。最终对炉膛展开了仿真模拟,发现最高温度和较大吸热量均出现在燃烧器的顶部位置,最高温度可以达到2000 K。炉膛中部氧气浓度值减少,每层燃烧器部分区域因为空气填补存有起伏波动,燃尽风区域得到很多填补,但是随着高度的升高氧含量逐渐降低。为后续炉膛内结焦难题的解决和运行燃烧的改善提供指导和借鉴。

In order to enhance combustion characteristics and address the issue of coking in boilers,this paper selects 600 MW ultra-supercritical,direct-flow,counterflow combustion boiler as the research subject.The CFD numerical simulation method is employed to conduct simulated analyses of two-phase flow,combustion phenomena,and heat and mass transfer characteristics inside the furnace of the boiler.Based on data analysis,temperature contour maps for burner and air exhaust locations,furnace temperature field maps,as well asO_(2)concentration,CO concentration,and CO 2 contour maps along the height direction of the furnace are presented.The paper elaborates on the aerodynamic field and temperature gradient within the furnace.Finally,a simulation of the furnace reveals that the highest temperature and significant heat absorption occur at the top position of the burner,with the maximum temperature reaching 2000 K.In the middle section of the furnace,the oxygen concentration decreases,and fluctuations in some areas of each layer of burners exist due to air replenishment.The region of air exhaustion receives considerable replenishment,but the oxygen content gradually decreases with increasing height.This study provides guidance and reference for solving the coking problem in the furnace and improving combustion operation in subsequent stages.