Low Cycle Fatigue on Coil Retaining Rings and Turbogenerator Rotors: a preliminary analysis

In the present paper a hybrid approach, combining FEM simulations in the elastic field and a numerical data processing using elasto-plastic models, is applied. The aim is to investigate the main criticalities in ring and rotor designs and to estimate the maximum number of cycles up to defect initiation. In a next stage, an experimental campaign will be set up for a complete low cycle fatigue material characterization and a wide comparison among modern theories on fatigue will be performed. The present research, whose final goal is to develop a user-friendly tool for generator component life estimation at design and refurbishments stages, is supported by an Italian industry operating in the field of turbine and generators.