Vibration analysis of distributed-lumped rotor systems

Multivariable Hybrid Models for Rotor-Bearing Systems

“…Generally, when a part of the rotor bearing system, consists of n successive distributed shaft elements, then the overall dynamic sti!ness matrix could be expressed as [15] […”

“…However, they pointed out that numerical computation considers the denominator terms also in equation (42) and this leads to a signi"cant error in the computation of the damped natural frequencies by the DSMM [15]. Meanwhile the vibration of the mth lumped disc in vertical y direction which results from the vertical excitation force at lth lumped element can be computed easily using the #exibility matrix in equation (40) so that…”

“…When implemented for rotors mounted on #uid "lm bearings, two identical characteristic determinants results. However, the numerical computation of the damped natural frequencies using DSMM yields a signi"cant unavoidable error [15]. Regardless of this limitation, the dynamic sti!ness matrix method is described as an accurate technique for frequency response determination [15].…”

Study on the dynamic performance of concrete mixer's mixing drum

“…Kabus et al (2014) dealt with the same issue as Rahnejat and Gohar (1979), where numerical analysis of non-Hertzian tilted rollers to races contacts are required for a misaligned rotorbearing system. Aleyaasin et al (2000) and Tsai and Huang (2013) used transfer matrix method to establish the dynamic model for rotor-bearing system with multiple degrees of freedom. The critical speed, unbalanced response and vibration mode are studied.…”

Prediction of lateral vibration characteristics of a full-size rotor-bearing system by using those of its scale models

“…: +886 7 8100888x5230; fax: +886 6 2808458. rotor-bearing systems. Aleyaasin et al [5] have used the dynamic stiffness matrix method to perform the lateral vibration analysis of rotor-bearing systems. In this report, the shaft segment and disc (or bearing) are, respectively, modelled as distributed (mass) element and lumped (mass) element, so that the entire rotor-bearing system can be modelled by the combination of a series of distributed and lumped (mass) elements.…”