直流锅炉水冷壁变工况的适应性

ADAPTABILITY OF THE WATER-WALL IN ONCE-THROUGH BOILER TO OFF-DESIGN CONDITION

简述了直流锅炉水冷壁的型式及其特点。通过华能沁北发电公司国产超临界直流锅炉水冷壁不同工况金属壁温的偏差分析,认为垂直水冷壁出口温度偏差明显大于螺旋水冷壁出口温度偏差。采用下部螺旋水冷壁和上部垂直水冷壁的结构,可以较好地解决变工况下的传热恶化和垂直水冷壁流量分配不均的问题;水冷壁变工况运行良好,锅炉起动的经济性和安全性都达到了大容量直流锅炉的水平。

The types and features of waterwall in oncethrough boilers have been briefly described.Through analysis of metalic wall temperature deviation under various conditions of the waterwall in the first home made supercritical oncethrough boiler of Huaneng Qinbei Power Generation Company,the results obtained are as follows: the outlet temperature deviation of vertical waterwall is obviously greater than that of spiral waterwall;adopting spiral waterwall in the lower part,and adopting vertical waterwall in the upper part,the problems of heat transfer deterioration and nonuniform distribution of the flowrate in vertical waterwall under offdesign condition can be comparatively well solved.The operation under offdesign condition is good,the economic behavior and reliability of boiler startup all to be reached a level of a largecapacity oncethrough boiler.