The work in this M. Sc. thesis may be subdivided into three areas where research has been done: interactive numerical analysis, modelling of hydraulic turbine-generator lateral vibrations, and machine health monitoring. In the first area, a unique scheme was developed for creating interactive numerical analysis programs for Graphical User Interface environments. The scheme, utilizing object oriented programming, involves a Framework object to which Element objects are added for display, and Tool objects are added to manipulate Element objects. In the second area, a program was developed to model the lateral vibrations of hydraulic turbine-generators. The finite element model uses a nonlinear static displacement computation algorithm, with a linear response module and QR eigenvalue module to calculate response, natural frequencies and stability of a rotating Timoshenko beam with rigid rotors and coupling elements. The effects of the static axial and torsional shaft forces, the guide bearing forces, the generator magnetic forces and the turbine hydraulic forces are included in the model. The effects of parameters such as the rotation speed, imbalances, coupling stiffness, coupling misalignment, bearing misalignment, bearing wear, generated power, generator stator and rotor misalignment are demonstrated for a simply supported beam and for an actual hydro-generator unit. In the third area, the use of finite element models for machine health monitoring is examined, and terms and procedures are set out for a method of trend analysis in which variables characterizing the deterioration mechanism are calculated from measurements and used to predict the machine life or a maintenance period. Problems associated with predicting machine deterioration from vibration measurements are discussed with regards to a single degree-of-freedom example, a two degree-of-freedom example and a numerical turbine-generator example.
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