Software like is used to create finite element models. Case studies show how to adjust bearing coefficients, seal stiffness, and disk locations to match measured critical speeds.
A high-speed turbocharger used in diesel locomotives experienced severe subsynchronous vibration. Analysis revealed the original three-axial groove journal bearings were unstable; replacing them with a three-lobe bearing design provided the necessary damping to stabilize the system. Centrifugal Compressor Critical Speed: turbomachinery rotordynamics with case studies pdf
: At 85% of operating speed, a subsynchronous vibration at 0.43x appeared, growing rapidly until a shutdown was triggered. Software like is used to create finite element models