Stability of a Turbine-Generator Rotor Including the Effects of Certain Types of Steam and Bearing Excitations

The effects of certain steam forces and bearing oil-film forces on vibration stability of a turbine-generator rotor are considered. A matrix method for systematically calculating the characteristic equation of a real rotor is developed with the aid of complex notation. The matrices are 4 × 4 in size. Pedestal effects are not included. A simple example is worked out and the results are compared to those obtained by another author. Complete agreement is obtained in the determination of the characteristic equation.