Analytical modeling of asymmetric multi-segment rotor – bearing systems with Timoshenko beam model including gyroscopic moments

• Forced response of an asymmetric rotor – bearing system is determined analytically.
• The method developed can provide highly accurate predictions.
• The method provides considerable reduction in computational time compared to FEM.
• Efficiency of the method increases when modifications in the system are required.

In this study, analytical modeling and an analysis approach for asymmetric multi-segment rotor – bearing systems are presented. Timoshenko beam model which includes the effect of gyroscopic moments is employed for modeling rotor segments. Instead of applying FEM, sub-segment Frequency Response Functions (FRFs) are obtained analytically, and sub-segment FRFs obtained are coupled by using receptance coupling method. Bearing properties are included into system dynamics by employing structural modification techniques. The proposed analytical model is verified by using FEM approach. It is shown that using analytical model and receptance coupling, compared with FEM, reduces computational time drastically without losing accuracy.