The Influence of Blade Row Dynamics on Lateral and Torsional Shaft Vibrations in Steam Turbines

摘要

The aim is to obtain simple models that can be coupled to shaft models which are used in general purpose software for analyzing its rotor-dynamic behavior. Two modal models of the blade row have been developed and introduced in the 1D beam model of the rotor, for analyzing its behavior, separately for lateral and torsion vibrations. The methodology has been applied to the last stage blade row of a steam turbine. The results of the analysis show that besides the known influence of shaft torsion vibrations on blade row vibrations, also lateral shaft vibrations can excite easily the blade row vibrations and conversely that blade row vibrations excited by the steam flow can be detected by lateral vibration measurements in the bearings of the steam turbine.