超临界锅炉垂直水冷壁管壁温度敏感性分析

超临界直流锅炉运行时,由于工况变化复杂,易导致垂直水冷壁出口处管壁温度急剧增长,致使水冷壁超温爆管,从而对锅炉的运行安全造成极大的威胁。针对此问题,利用最小二乘支持向量机对超临界锅炉垂直水冷壁出口处管壁温度进行建模,并运用此模型分析运行参数与垂直水冷壁出口处管壁温度的关系,进而获得垂直水冷壁出口处管壁温度与相关因素间的敏感度;确定在垂直水冷壁出口处管壁温度趋近报警温度时的最敏感运行参数,并对其进行有效调节。实际运行情况证明此敏感度对调节控制垂直水冷壁出口处管壁温度具有指导意义。

Sensitivity Analysis on Outlet Metal Temperature of Vertical Water Wall Tube in Supercritical Boiler

When supercritical once-through boiler operates,complex changes in the working conditions could easily lead to sharp increase in tube-wall temperature at the outlet of vertical water wall,which results in over temperature and tube burst on water wall and threatens the safe operation of the boiler.Accordingly,the LS-SVM（least square support vector machine） was used to construct model for outlet metal temperature of vertical water wall tube in supercritical boiler.The relation between running parameters and the outlet metal temperature was analyzed based on the model.Then the sensitivity of the outlet metal temperature to relevant factors was obtained;the most sensitive running parameters when the outlet metal temperature approached the alarm temperature were determined and adjusted effectively.It is verified in practice that the sensitivity has some instructional meaning for controlling and adjusting the outlet metal temperature of vertical water wall tube in supercritical boiler.