300MW机组锅炉启动过程的优化研究

Study on Optimization of the Starting Process of 300MW Sets' Boilers

用三维有限元理论计算300MW机组锅炉汽包在内压作用下的应力场,得到锅炉汽包下降管处的理论应力集中系数,并用热弹性理论计算准稳态下汽包的热应力。采用美国ASME标准计算锅炉汽包疲劳寿命,以不同阶段升压范围所经历的时间步长为优化参数,以降低疲劳寿命损耗和缩短启动时间为双目标,建立了300MW机组锅炉启动过程的优化模型。通过计算得到了锅炉冷态启动和热态启动的优化曲线。并应用于某电厂300MW机组1025t/h锅炉实际运行,效果良好。所得到的优化启动曲线对300MW机组锅炉运行具有指导意义。图3,表2。

The theoretical stress concentration factor, for internal pressure, at the junction of a 300 MW set＇s boiler drum and its downcomer, is obtained by a 3-dimensional finite element stress field calculation. Simultaneously, the them,at stress of the drum under steady condition is also calculated. The life expectancy of the boiler drum is then calculated according to ASME Code and, taking the time interval of pressure escalation steps as the optimizing parameter, with reducing life consumption and starting time as the dual goal to be aspired, an optimization model of the 300 MW set＇s boiler starting process is built up. Optimized starting curves for the boiler＇ s cold and hot starting have been calculated and applied with good results to a 1 025 t/h boiler of a certain power plant＇s 300 MW set. These optimized starting CUB＇es may serve as guides for operating boilers of 300 MW power sets. Figs 2, tables 2 and refs 8.