超超临界燃煤机组已成为当前主流燃煤发电主力机组，具有效率高、煤耗低、排放低等特点，从煤质和火电运行情况来看，我国燃煤发电面临煤质多变、环境复杂等恶劣运行条件的挑战，又需承担电力系统调峰和污染物超低排放等经济、社会职责，其重要性不言而喻。大型高参数机组中，热量从炉到锅的传递过程是整个机组的关键环节之一。本文研究了某1000 MW超超临界塔式锅炉炉侧和锅侧的耦合模拟模型，从而实现炉和锅的匹配，进而研究了变煤种和变工况等对超超临界锅炉运行的影响。 在模型的建立中，炉侧采用FLUENT进行三维炉膛燃烧和传热模拟，锅侧采用MATLAB进行基于炉侧受热面网格的受热蒸发系统的三维仿真计算，耦合模拟的基本思路是锅侧将炉侧得到的热流密度作为热源输入，用于确定壁面温度，炉侧则将壁温作为边界条件从而调整燃烧状况，热流密度和壁面温度数据通过网格节点进行传输。 本文首先对超临界锅炉的额定工况进行了研究，从炉侧燃烧器截面以及炉膛中心截面上的速度、温度和燃尽率分布分析，得到炉膛内的主要反应区域与燃烧情况，揭示了热流密度的分布和对壁面温度的影响规律。蒸发系统的吸热量主要集中在水冷壁，在螺旋管圈中，燃烧器区域的壁面温度波动最大，在垂直管圈中，沿着管长方向壁温先升高后降低。对无结渣工况和结渣工况进行对比，发现结渣主要影响炉膛的壁面温度分布，从而影响炉膛内的烟气温度和热流密度在壁面上的分布。 煤粉参数改变时发现，细度主要影响燃烧距离和燃尽率，细度小的工况热流密度和温度分布更为均匀，细度大的工况中，出口飞灰颗粒的含碳量更高，总放热量小，水冷壁的吸热量也更小。烟煤煤质的改变对于超临界锅炉的传热影响不是太大，水冷壁和换热器吸热量比例都基本接近。在不同负荷的运行工况下，锅炉连续最大出力工况（BMCR）和75%BMCR工况下炉膛中烟气温度分布比较相近，而煤粉密度和风速小的50%BMCR工况下烟气温度明显比其他两个工况要低。三个工况下的换热器吸热量比例基本一致，在高热流密度区，BMCR和75%BMCR工况中水工质沿管长呈上升趋势，50%BMCR在两相区温度呈下降趋势。

Supercritical coal-fired units have become the mainstream coal-fired generating units, because of the characteristics of high efficiency, low coal consumption and less emission. In view of coal quality and thermal power operation situation, coal-fired generation in China is confronted with the challenge of the difficult operating conditions, such as the changeable quality of coal and complicated environment. Supercritical coal-fired units need to bear the economic and social responsibilities such as peak load regulation and ultra-low pollutant emission of power system, which is self-evident and needs to be further researched. The transfer process of heat from furnace to boiler in large high parameter unit is the key link of the whole unit. In this paper, the coupling simulation model of a 1000MW supercritical tower boiler is implemented to realize the matching of furnace and boiler, and the model is used to research the influence of variable coal and variable working conditions on the operation of ultra-supercritical boilers.In the establishment of the model, FLUENT was used to simulate the three-dimensional furnace combustion and heat transfer simulation, and MATLAB was used to simulate the three-dimensional heating evaporation system of boiler side based on the grid nodes of the heating surface in the furnace side. The basic principle of the coupling is that the heat flux obtained from the furnace side is used as the heat source input of boiler side to compute the temperature of water wall, and then the wall temperature is obtained as the boundary condition of the furnace side, during this process, the heat flux density and the wall temperature data are transmitted through the grid nodes of the heating surface. This model is used to study the rated conditions of supercritical boilers, based on the analysis of the distribution of the velocity, temperature and burnout rate in the section of furnace near the burners, the main reaction areas and combustion conditions in the furnace are obtained, and the distribution of heat flux and the influence on wall temperature are obtained. The analysis of the boiler side shows that the heat absorption of the evaporation system is mainly concentrated in the water wall. In the spiral tubes, the wall temperature near the burner area fluctuates the most. In the vertical tubes, wall temperature rises first and then decreases after about 75m. The maximum temperature difference between adjacent tube walls along the furnace width is within 10 ℃. The slag working condition and no-slagging condition are compared and found that the slagging mainly influences the temperature distribution of the furnace wall, which affects the distribution of flue gas temperature and heat flux density on the heating surface. When the pulverized coal changes, the fineness mainly affects the burning distance and the burnout rate, in small fineness condition, heat flux density and the temperature distribution is more even, in big fineness condition, the carbon content of fly ash particle in export is higher, the total release heat is less, the water wall also absorbs less heat. When the coal is bituminous coal, the influence of the change of coal quality is not very big for the heat transfer of the supercritical boiler, and the ratio of heat absorption of water wall and heat exchanger is basically close. Under the operating conditions of different loads, the flue gas temperature distribution in the furnace under BMCR and 75%BMCR conditions are similar, and the flue gas temperature is obviously lower than the other two working conditions under the 50%BMCR working condition with small pulverized coal density and low wind speed. The proportion of heat exchanger in three working conditions is basically the same, in the high heat flux zone, the temperature of water shows an upward trend along the tube length in the BMCR and 75%BMCR conditions, and in the 50%BMCR conditions, temperature in the two-phase region is decreasing.