Temperature Distribution Of The Steam Turbine In The Cylinder Holding With Numerical Simulation

As the steam turbine plant developing toward the direction of large capacity and high parameter, the loss after the plant fault is becoming larger. Research on emergency and optimization measures after the plant fault, not only can improve the maintenance efficiency, but also can improve the economic benefits of the steam turbine. Cylinder holding means turning off the drain valves and inlet valves, plugging the shaft sealing, isolating the steam turbine from the outside in order to avoid the deformation because of the temperature difference between upper and lower cylinder. Research on the temperature field distribution and the change law of the temperature field distribution under the condition of cylinder holding can help us to know and predict the deformation and stress change of the cylinder and other internal structures in the process of cylinder holding.In this article, the finite element mode of the high and middle pressure cylinder and rotor of the 600 MW steam turbine was built to simulate the heat transferring problem. With this model,heat transfer coefficient in the process of cylinder holding is obtained by the method of comparing the actual monitoring data to the trial computing results. Then, thermal steady analysis is carried out to get the steady temperature field distribution of the whole steam turbine in the normal operating condition. At last, transient analysis was executed to learn the whole cooling process. With the results of the simulating, temperature changes of the 1 #, 2 # bearing bushes of high and middle pressure cylinder under different conditions could be gained and some effective measures which help to recover after the generator fault could be provided to the operator.Through the work above, thermal problem of cylinder holding was understood which could help to speed up the cooling process of the steam turbine after failure.