High cycle fatigue cracks at radial fan impellers caused by aeroelastic self-excited impeller vibrations: Part I - case history, root cause analysis, vibration measurements

摘要

Hydrogen-cooled two-pole turbogenerators are equipped with one single-state radial fan for cooling gas ventilation. The impellers with outer diameters of up to 1.5m operate with 3000 rpm or 3600 rpm. High cycle fatigue cracks have occurred at two radial fan impellers operated at 3000 rpm.