When dealing with slender rotors, several vibrations modes can be relevant to define their dynamic behavior in working conditions. Considering long lathing bars, for example, it is almost impossible not to encounter one or more of their critical speeds during machining. Therefore, modelling slender rotors is essential to predict and analyse such conditions. The lumped parameters approach is adopted in this study as it enables to consider the compliance of the system's constraints. The stiffness matrix is obtained considering a succession of Timoshenko elements beams, and the stiffness of the constraints is addressed based on the results of experimental modal analyses. The equations of motion are derived from the Lagrange equation and implemented in MATLAB® Simulink. The model is then validated by comparing the numerical frequency response functions with the experimental ones. Numerical results are proved to be consistent with linear theory of rotor dynamics and can be used to predict the behavior of slender rotors of different materials.
Caselli, L., Rizzitelli, M., Rivola, A., Troncossi, M. (2024). On the numerical modelling of a rotor system to support the analysis of experimental vibration signals for the condition monitoring of a CN lathe integrated with an automatic bar feeder. Leuven : KU Leuven, Departement Werktuigkunde.
On the numerical modelling of a rotor system to support the analysis of experimental vibration signals for the condition monitoring of a CN lathe integrated with an automatic bar feeder
Caselli L.;Rivola A.;Troncossi M.
2024
Abstract
When dealing with slender rotors, several vibrations modes can be relevant to define their dynamic behavior in working conditions. Considering long lathing bars, for example, it is almost impossible not to encounter one or more of their critical speeds during machining. Therefore, modelling slender rotors is essential to predict and analyse such conditions. The lumped parameters approach is adopted in this study as it enables to consider the compliance of the system's constraints. The stiffness matrix is obtained considering a succession of Timoshenko elements beams, and the stiffness of the constraints is addressed based on the results of experimental modal analyses. The equations of motion are derived from the Lagrange equation and implemented in MATLAB® Simulink. The model is then validated by comparing the numerical frequency response functions with the experimental ones. Numerical results are proved to be consistent with linear theory of rotor dynamics and can be used to predict the behavior of slender rotors of different materials.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.