百万等级核电半速汽轮发电机组低压转子轴承支撑刚度的研究

建立了汽轮机低压转子落地式轴承座刚度分析有限元模型，采用三维有限元软件Ansys分析了使用弹簧基础的百万等级核电半速汽轮发电机组低压转子落地式轴承座的刚度，并在此基础上计算和分析了轴承座刚度在一定范围内变化时对大型汽轮机低压转子临界转速的影响．结果表明：利用汽轮机低压转子落地式轴承座刚度分析有限元模型计算得到的低压转子轴承座刚度与经验数值量级相同，但大小有一定差异．汽轮机低压转子临界转速对低于一定数值的落地式轴承座支撑刚度变化更敏感，因此在设计时应保证足够大的轴承座刚度．

Study on Bearing Support Stiffness of LP Rotor for a 1 000 MW Nuclear Power Half-speed Turbine-Generator Set

A finite element model was established for ground standing type bearing support of LP rotor for a 1 000 MW nuclear power half-speed turbine-generator set with spring foundation, with which the support stiffness was analyzed using 3D finite element software Ansys. Effects of the support stiffness on critical speed of the LP rotor were calculated and analyzed on the basis of above stiffness analysis. Results show that the value of bearing support stiffness calculated with the model is different from but in same order of maganitude with that of empirical value. The critical speed of LP rotor is greatly affected by the bearing support stiffness lower than a certain value, therefore for safety operation purposes, the bearing supports should be designed with higher stiffness.