Sommerfeld effect characterization in rotors with non-ideal drive from ideal drive response and power balance

• Multi-energy domain model of rotor system with its drive, eccentric rotor and gyroscopic coupling
• Passage through resonance with finite drive power
• Combined finite element and bond graph modeling to explore passage through resonance (Sommerfeld effect) in rotor dynamic systems
• Guidelines to size actuators for rotor dynamic systems.

Rotor dynamic systems are often analyzed with ideal drive assumption. However, all drives are essentially non-ideal, i.e., they can only provide a limited amount of power. One basic fact often ignored in rotor dynamics studies is that the drive dynamics has complex coupling with the dynamics of the driven system. Increase in drive power input near resonance may contribute to increasing the transverse vibrations rather than increasing the rotor spin, which is referred to as the Sommerfeld effect. In this article, we generate the rotor response with finite element (FE) model by assuming an ideal drive. Thereafter, the rotor system’s response with ideal drive is used in a power balance equation to theoretically predict the amplitude and speed characteristics of the same rotor system when it is driven through a non-ideal drive. The integrated system with drive-rotor interaction is modeled in bond graph (BG) form and the transient analysis from the BG model is used to validate the theoretical results. The results are important from the point of actuator sizing for rotor dynamic systems.