In that context, the simulation of the rotor including the non-linear effects of ball bearings, (with additional squeeze film damper to assure sufficient damping) is essential for an apriori analysis of the system’s dynamics. For that purpose, a dynamic model of the ball bearings including the contact dynamics between the balls, the inner and outer bearing raise and the cage was established and is investigated in detail.
The ball bearings and the squeeze film dampers are implemented with high modelling depth, taking into account all relevant design parameters like initial load, contour of the ball bearings, seals of the squeeze film damper etc.. The system’s eigenbehaviour is investigated using a non-linear and a linearized approach for the stiffness and damping properties of the bearings.
Finally, the results in term of time dependent rotor displacements (under a given rotational frequency of the turbocharger) are examined and compared with measurements to validate the simulation model.