1000MW超超临界汽轮机转子启动过程的热应力分析

Analysis on thermal stress of 1000 MW ultra supercritical turbine rotor during startup

超超临界汽轮机转子工作在高蒸汽参数的恶劣环境下,特别是在机组参与调峰等变工况运行时,转子材料内部产生极大的热应力,如果运行操作不当将会给转子带来巨大的损伤。以1000 MW超超临界汽轮机高压转子为研究对象,运用转子热应力分析理论,依据现场实测数据计算得到高压转子各级的蒸汽参数及其换热系数,建立转子热应力有限元计算的边界条件。运用ANSYS软件分别对机组在冷态和温态启动过程中高压转子的温度场及应力场进行计算,比较了2种工况下高压转子的热应力谱。计算、分析结果可为1000MW超超临界汽轮机组的启动和变工况运行提供参考。

The rotor of the ultra supercritical steam turbine operates under severe environment with high steam parameters.Especially,when the unit operates under variable condition,such as taking part in peak shaving,a great thermal stress may occur inside material of the rotor,and improper operation will damage the rotor seriously.Taking the HP rotor of 1 000 MW ultra supercritical steam turbine as research object,using the rotor thermal stress analysis theory,according to the site measured data,the various level steam parameters of the HP rotor and the heat transfer coefficient were calculated,and the boundary conditions of finite element calculation of rotor thermal stress were established.Using the software ANSYS,the temperature field and the stress field of the HP rotor during cold startup process and warm startup process were calculated respectively.The thermal stress spectrums of the HP rotor under the two conditions were compared.The results of calculation and analysis can be used as reference for 1 000 MW ultra supercritical turbine set in startup and operation under variable condition.