Analysis of the dynamic behavior of onboard rotors in non-linear regimes under the influence of parametric uncertainties

In recent decades, a significant advance in the understanding of the dynamic behavior of rotors has been observed, including the capacity to model and forecast the physical behavior of these systems. The emergence of novel applications seeks to optimize performance and cost-effectiveness maintaining safe operating conditions and pushing rotating systems to their limits. Therefore, this contribution presents a combined numerical and experimental investigation of the nonlinear behavior exhibited by rotating systems subjected to base excitations. A comprehensive model incorporates nonlinear behavior resulting from large displacements as derived from the Lagrange’s equations and the finite element (FE) method. The deterministic model is extended to encompass bearings with stochastic stiffness. A rotating machine with a flexible shaft, a rigid disk, and supported by two bearings is evaluated. A dedicated test bench was used to compare the vibration responses obtained by using the implemented mathematical model with the experimental measurements. The obtained results demonstrate the representativeness of the considered FE model.