Numerical simulation of unbalance vibration for 600MW supercritical steam turbine

This paper takes a 600 MW supercritical steam turbine with a combined rotor for high and intermediate pressure parts (HIP) as an object to analyze the unbalance vibration of the HIP rotor. First, a model for the HIP rotor is established with lumped parameter method and the critical speeds and vibration modes of the rotor are calculated based on the transfer matrix method. The results calculated with Prohl and Riccati methods are compared and tested with the measurement values. Then, the influence of bearing stiffness to critical speeds is discussed here. Finally, the vibration response of the rotor is calculated with simulating unbalance at different places and speeds, and the influence of unbalance failures on the shaft vibration is discussed by analyzing the character of the unbalance response.